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1
Manzanares-Papayanopoulos, Emilio. "Bulk and interfacial molecular structure near liquid-liquid critical points." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327623.
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Bribesh, Fathi. "Free surface films of binary liquid mixtures." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/9810.
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Model-H is used to describe structures found in the phase separation in films of binary liquid mixture that have a surface that is free to deform and also may energetically prefer one of the components. The film rests on a solid smooth substrate that has no preference for any component. On the one hand the study focuses on static aspects by investigating steady states that are characterised by their concentration and film height profiles. A large variety of such states are systematically analysed by numerically constructing bifurcation diagrams in dependence of a number of control parameters. The numerical method used is based on minimising the free energy functional at given constraints within a finite element method for a variable domain shape. The structure of the bifurcation diagrams is related to the symmetry properties of the individual solutions on the various branches. On the other hand the full time dependent model-H is linearised about selected steady states, in particular, the laterally invariant, i.e.\ layered states. The resulting dispersion relations are discussed and related to the corresponding bifurcation points of the steady states. In general, the results do well agree and confirm each other. The described analysis is performed for a number of important cases whose comparison allows us to gain an advanced understanding of the system behaviour: We distinguish the critical and off-critical case that correspond to zero and non-zero mean concentration, respectively. In the critical case the investigation focuses on (i) flat films without surface bias, (ii) flat films with surface bias, (iii) height-modulated films without surface bias, and (iv) height-modulated films with surface bias. Each case is analysed for several mean film heights and (if applicable) energetic bias at the free surface using the lateral domain size as main control parameter. Linear stability analyses of layered films and symmetry considerations are used to understand the structures of the determined bifurcation diagrams. For off-critical mixtures our study is more restricted. There we consider height-modulated films without and with surface bias for several mean film heights and (if applicable) energetic bias employing the mean concentration as main control parameter.
3
Fröba, Andreas P., Cristina Botero, Heiko Kremer, and Alfred Leipertz. "Liquid viscosity and surface tension by surface light scattering." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-196257.
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Fröba, Andreas P., Cristina Botero, Heiko Kremer, and Alfred Leipertz. "Liquid viscosity and surface tension by surface light scattering." Diffusion fundamentals 2 (2005) 69, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14402.
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5
De, Virgiliis Andres, and Kurt Binder. "Monte Carlo study of transport phenomena in surface binary alloys." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-194655.
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De, Virgiliis Andres, and Kurt Binder. "Monte Carlo study of transport phenomena in surface binary alloys." Diffusion fundamentals 3 (2005) 12, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14299.
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Schob, Arne, and Frank Cichos. "Molecular motion in thin liquid films near surface steps." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-196327.
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Schob, Arne, and Frank Cichos. "Molecular motion in thin liquid films near surface steps." Diffusion fundamentals 2 (2005) 76, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14409.
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Zhu, Qingyong, Geoffrey D. Moggridge, and Carmine D’Agostino. "A local composition model for the prediction of mutual diffusion coefficients in binary liquid mixtures from tracer diffusion coefficients: A local composition model for the prediction of mutual diffusioncoefficients in binary liquid mixtures from tracer diffusion coefficients." Diffusion fundamentals 24 (2015) 58, S. 1, 2015. https://ul.qucosa.de/id/qucosa%3A14577.
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Zhu, Qingyong, Geoffrey D. Moggridge, and Carmine D’Agostino. "A local composition model for the prediction of mutual diffusion coefficients in binary liquid mixtures from tracer diffusion coefficients." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-198798.
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Richardson, David Jeremy. "Enhanced mass transport in liquid-saturated porous media due to surface shear." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/27112.
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The principal aim of this work was the development of a novel conductivity probe for measuring solids concentrations in slurries. The relevance of the thesis to this probe is that it requires rapid transport of aqueous electrolyte through a porous disc to an internal conductivity cell.
12
Brown, Matthew D. "Verification of universal surface scaling behavior in critical binary liquid mixtureswith neutron and x-ray reflectometry." Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/320.
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Thapa, 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.
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Stoodley, Paul. "The influence of liquid flow and nutrients on biofilm structure and behaviour." Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286538.
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Brown, Matthew D. "Verification of universal surface scaling behavior in critical binary liquid mixtures with neutron and x-ray reflectometry." Diss., Kansas State University, 2007. http://hdl.handle.net/2097/320.
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Doctor of PhilosophyDepartment of Physics
Bruce M. Law
We have studied two critical binary liquid mixtures in the mixed phase regime with x-ray and neutron reflectometry to verify universal critical scaling at a non-critical interface. We compared our results with previous results obtained with ellipsometry. At a solid-liquid or liquid-vapor interface of an AB binary liquid mixture the component with the lower surface tension will dominate that interface. If the surface tension differential between the components of the mixture is large enough the composition of the surface layer will loose its dependence on. This case is referred to as strong adsorption. We study the case of strong adsorption for a binary liquid mixture at the critical composition with respect to the demixing phase transition. Sufficiently close to the critical temperature Tc the influence of bulk critical behavior is expected to dominate the way the surface adsorption layer decays with depth z from the surface composition to the bulk composition. The length scale of the decay profile is expected to be proportional to the composition correlation length, and is expected to scale with a universal composition scaling function. In a neutron reflectometry study of a critical mixture of D2O and 3-methylpyridine against a quartz substrate we verify universal critical scaling using a scaling function previously used to describe ellipsometry data. In an x-ray reflectometry study of the liquid-vapor interface of a critical mixture of n-dodecane and 1,1,2,2 tetrabromoethane, which had previously been studied with ellipsometry, we find that we are able to describe all data by using the same scaling function provided that we account for non-critical, system dependent surface structure as well. We are also able to simulate ellipsometry with our mathematical profile model and compare the simulation to the previous ellipsometry data.
16
LIU, WEN. "TRANSPORT PHENOMENA ASSOCIATED WITH LIQUID METAL FLOW OVER TOPOGRAPHICALLY MODIFIED SURFACES." UKnowledge, 2012. http://uknowledge.uky.edu/me_etds/16.
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Brazing and soldering, as advanced manufacturing processes, are of significant importance to industrial applications. It is widely accepted that joining by brazing or soldering is possible if a liquid metal wets the solids to be joined. Wetting, hence spreading and capillary action of liquid metal (often called filler) is of significant importance. Good wetting is required to distribute liquid metal over/between the substrate materials for a successful bonding.
Topographically altered surfaces have been used to exploit novel wetting phenomena and associated capillary actions, such as imbibitions (a penetration of a liquid front over/through a rough, patterned surface). Modification of surface roughness may be considered as a venue to tune and control the spreading behavior of the liquids. Modeling of spreading of liquids on rough surface, in particular liquid metals is to a large extent unexplored and constitutes a cutting edge research topic.
In this dissertation the imbibitions of liquid metal has been considered as pertained to the metal bonding processes involving brazing and soldering fillers. First, a detailed review of fundamentals and the recent progress in studies of non-reactive and reactive wetting/capillary phenomena has been provided. An imbibition phenomenon has been experimentally achieved for organic liquids and molten metals during spreading over topographically modified intermetallic surfaces. It is demonstrated that the kinetics of such an imbibition over rough surfaces follows the Washburn-type law during the main spreading stage. The Washburn-type theoretical modeling framework has been established for both isotropic and anisotropic non-reactive imbibition of liquid systems over rough surfaces. The rough surface domain is considered as a porous-like medium and the associated surface topographical features have been characterized either theoretically or experimentally through corresponding permeability, porosity and tortuosity. Phenomenological records and empirical data have been utilized to verify the constructed model. The agreement between predictions and empirical evidence appears to be good. Moreover, a reactive wetting in a high temperature brazing process has been studied for both polished and rough surfaces. A linear relation between the propagating triple line and the time has been established, with spreading dominated by a strong chemical reaction.
17
Khoo, Boo Cheong. "A numerical and experimental study of the scalar transport at a turbulent liquid free surface." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/32572.
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Walker, Glen William, and not available. "Electron Transfer Reactivity, Synthesis, Surface Chemistry and Liquid-Membrane Transport of Sarcophagine-Type Poly-Aza Cage Complexes." The Australian National University, 1997. http://thesis.anu.edu.au./public/adt-ANU20010702.124104.
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[Formulae and special characters can only be approximated here. Please see the pdf version of the Abstract for an accurate reproduction.]
The kinetics for outer-sphere electron transfer between a series of cobalt(II) poly-aza
cage ligand complexes and the iron(III) sarcophagine-type hexa-aza cage complex,
[Fe(sar)]3+ (sar = 3,6,10,13,16,19-hexaazabicyclo[6.6.6]icosane), in aqueous solution
have been investigated and the Marcus correlation is used to deduce the electron self-exchange rate constant for the [Fe(sar)]3+/2+ couple from these cross-reactions. The
deduced electron self-exchange rate constant is in relatively good agreement with the
experimentally determined rate constant (k ex calc = 4 ´ 10 5 M -1 s -1 ; k ex obs = 8 ´ 10 5 M -1
s -1 ). The successful application of the Marcus correlation to the electron transfer
reactions of the Fe cage complex is consistent with the trend for the Co, Mn, Ni and Ru
cage complexes which all follow the pattern of outer-sphere electron transfer reactivity
expected from the Marcus-Hush formalism. A comparison of predictions based on the
Marcus correlation with the experimentally determined kinetics of an extended series of
cross reactions involving cobalt cage complexes with low-spin-high-spin cobalt(III)/(II)
couples shows that electron transfer reactions involving large spin changes at the metal
centre are not necessarily anomalous in the context of the adiabatic Marcus-Hush
formalism. The results of this study also show that for suitable systems, the Marcus
correlation can be used to reliably calculate the rates of outer-sphere electron transfer
cross-reactions, with reaction free-energy changes spanning the range -6 to -41 kJ mol -1
and many different combinations of initial electronic configurations. Together, these
results provide a coherent and internally consistent set of experimental data in support
of the Marcus-Hush formalism for outer-sphere electron transfer. The results with the
caged metal-ion systems also highlight the special nature of the mechanism of electron
transfer in reactions of metal-aqua ions.
¶
A new range of symmetrically disubstituted hexa-aza sarcophagine-type cage
ligand complexes are prepared in this study by the base-catalysed co-condensation of
formaldehyde and a-methylene aliphatic aldehydes with cobalt(III) tris(1,2-diamine)
precursors in acetonitrile solution. Encapsulation reactions based on the condensation
of the weak carbon di-acids propanal and decanal with formaldehyde and the cobalt(III)
tris(1,2-diamine) precursors, [Co(en)3 ] 3+ (en = 1,2-ethanediamine) and D-lel3 -[Co((R,
R)-chxn)3 ] 3+ (chxn = 1,2-cyclohexanediamine), yield unsaturated cobalt(III) cage
complexes with an endo-cyclic imine function in each cap. The Co III -coordinated endo-cyclic imine units of the cage ligands are reactive electrophiles that are readily reduced
by the BH4 - ion to give the corresponding symmetrically di-substituted hexaamine
macrobicyclic cage ligands. The nitromethane carbanion is also shown to add at the
endo-cyclic imine function to yield a novel nitromethylated cage ligand complex. The
latter reaction introduces a new method for the regioselective functionalisation of cage
ligands at sites removed from the more commonly substituted bridgehead positions.
The capping of cobalt(III) tris(1,2-diamine)-type complexes with weak CH-acids
developed in this study introduces a new and more direct route to symmetrically di-substituted cage ligand complexes.
¶
A new range of cobalt(III) surfactant cage complexes, with linear octyl, dodecyl
and hexadecyl hydrocarbon chains built directly into the bridgehead structure of the
cage ligand, have been prepared by the base catalysed co-condensation of formaldehyde
and long chain aliphatic aldehydes with the tripodal cobalt(III) hexaamine complex,
[Co(sen)]3+ (sen = 4,4',4''-ethylidynetris(3-azabutan-1-amine)), in acetonitrile solution.
Chiral surfactant cage complexes are obtained by capping reactions beginning with the
optically pure L-[Co(sen)]3+ precursor complex. The cobalt(III) cage complexes with
octyl to hexadecyl substituents are surface active and reduce the surface tension of
water to levels approaching those of organic solvents. The dodecyl substituted cage
complex forms micelles in aqueous solution when the concentration of cage complex is
> 1 ´ 10 -3 mol dm -3 at 25 °C. The cobalt(III) cage head-group of these surfactants
undergoes an electrochemically reversible one-electron reduction to the corresponding
cobalt(II) cage complex. The reduction potential of the surfactant head group can be
tuned to more positive potentials by replacing the bridgehead hydrocarbon chain
substituent with an ether linked hydrocarbon chain. The cobalt(III) surfactant-cage
complexes are biologically active and are lethal to the tapeworm Hymenolepis diminuta,
and the vaginal parasites, Trichomonas vaginalis and Tritrichomonas foetus. The
surfactant cage complexes also cause lysis in red-blood cell membranes at
concentrations as low 10 -5 mol dm -3 . Their biological activity is linked to the high
head-group charge (3+) and size which cause distortions in biological membranes when
the membrane is treated with these molecules. The combination of the chemically
reversible outer-sphere redox properties of the cobalt cage head-groups and the chirality
of the head group introduces a new and possibly unique series of chiral surfactant
coordination complexes which are also redox active.
¶
The chiral carboxylic-acid ionophore, lasalocid A, has been used to promote the
selective supramolecular transport and extraction of cobalt(III) hexa-aza cage cations
and related tripodal cobalt(III) complexes. The conjugate base anion of lasalocid A
forms stoichiometric outer-sphere complexes with the cobalt(III) cage and tripod
complexes. These outer-sphere complexes are highly lipophilic and partition strongly
from water into a chloroform phase. The extraction of the dissymmetric cobalt(III)
complexes by the chiral polyether anion is enantioselective for many systems and
results in the partial resolution of initially racemic complexes in the aqueous phase. A
strong structural preference was demonstrated by the ionophore for symmetrically
disubstituted cobalt(III) hexa-aza cage cations with a D-absolute configuration of the
ligand about the metal-ion and an R configuration of the coordinated secondary amine
N-H groups. The lasalocid A anion was also shown to promote the transport of the
complexes, intact, across a chloroform bulk-liquid membrane against an NH4 +
concentration gradient. The transport of the cobalt(III) complexes was also
enantioselective and resulted in partial resolution of the initially racemic aqueous phase.
The most efficiently transported enantiomer of each complex was also the most
efficiently extracted isomer in all systems examined, consistent with a transport process
limited by interfacial diffusion. The magnitude of the enantiomer separation obtained in
some systems was sufficient to indicate that lasalocid A mediated extraction and
transport may become a practical method for the resolution of particular types of
kinetically-inert chiral metal-amine complexes.
19
Dygert, Clayton Edward. "Setback Distance Effect of Mitigating Nutrient Transport from Surface Applied Liquid Dairy Manure on Frozen/Snow Covered Soil." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1300979541.
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Sengupta, Anupam. "Nematic Liquid Crystals and Nematic Colloids in Microfluidic Environment." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2012. http://hdl.handle.net/11858/00-1735-0000-000E-00FA-B.
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Pollet, Benoît. "Transport-reactions dans les membranes echangeuses d'ions : extraction et transport facilites d'acides faibles, cas particulier de l'acide borique." Paris 6, 1987. http://www.theses.fr/1987PA066584.
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Le transport de substrat a travers une membrane echangeuse d'ions peut etre accelere lorsqu'un contre ion joue le role de transporteur. L'acide borique par reaction de neutralisation avec le contre ion hydroxyle et par reaction de condensation avec l'ion borate forme des complexes polyborates (tri-, tetra- et penta-borates) de stabilite moyenne
22
Akbar, Muhammad Khalid. "Transport Phenomena in Complex Two and Three-Phase Flow Systems." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4897.
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Two and three-phase flow processes involving gas, liquid and solid, are common in nature and industry, and include some of the most complex and poorly-understood transport problems. In this research hydrodynamics, heat and mass transfer processes in complex two and three-phase flows were investigated. The interfacial surface area concentration in a short vertical column subject to the through flow of fiber-liquid-gas slurry was experimentally measured using the gas absorption technique. The experimental data were statistically analyzed for parametric effects, and were empirically correlated. The absorption of a gaseous species by a slurry droplet with internal circulation and containing reactive micro-particles was simulated, and parametrically studied. The micro-particles were found to enhance the absorption rate. The absorption rate was sensitive to droplet recirculation, and shrinkage of particles with time resulted in declining absorption rates. The transport of soot particles, suspended in laminar hot gas flowing in a tube, was modeled and parametrically studied. Due to coupled thermal radiation and thermophoresis, a radially-nonuniform temperature profile develops, leading to sharp, non-uniform radial soot-concentration profiles. The assumption of monodisperse particles leads to over-prediction of thermophoresis. The transport and removal of particles suspended in bubbles rising in a stagnant liquid pool were modeled based on a Eulerian – Monte Carlo method. The bubble hydrodynamics were treated in Eulerian frame, using the Volume-of-Fluid (VOF) technique, while particle equations of motion were numerically solved in Lagrangian frame. The bubbles undergo shape change, and have complex internal circulation, all of which influence the particle removal. Model predictions were also compared with experimental data. Using a resemblance between two-phase flow in microchannels, and in large channels at microgravity, a simple Weber number-based two-phase flow regime map was developed for microchannels. Based on the available air-water experimental data, a criterion for the prediction of conditions that lead to flow regime transition out of the stratified-wavy flow pattern in horizontal annular channels was proposed. The thermocapillary effects on liquid-vapor interface shape during heterogeneous bubble ebullition in microchannels were analytically studied.
23
Meek, Chris. "Design Process for the Containment and Manipulation of Liquids in Microgravity." UKnowledge, 2019. https://uknowledge.uky.edu/me_etds/143.
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In order to enhance accessibility to microgravity research, the design process for experiments on the ISS must be streamlined and accessible to all scientific disciplines, not just aerospace engineers. Thus, a general design and analysis toolbox with accompanying best practices manual for microgravity liquid containment is proposed. The work presented in this thesis improves the design process by introducing a modular liquid tank design which can be filled, drained, or act as a passive liquid-gas separation device. It can also be pressurized, and used for aerosol spray. This tank can be modified to meet the design requirements of various experimental setups and liquids. Furthermore, rough simulations of this tank are presented and available to the user for modification. The simulation and design methodology for other general cases is discussed as well. After reading this thesis, the user should have a basic understanding of how liquids behave in microgravity. She will be able to run simple simulations, design, build, test, and fly a liquid management device which has been modified to suit the requirements of her specific experiment.
The general tank design can be manufactured using 3-D printing, traditional CNC milling, or a combination thereof. The design methodology and best practices presented here have been used to design tanks used in experiments on the International Space Station for Budweiser and Lambda Vision. Both tanks functioned nominally on orbit. While the specific data from these experiments cannot be presented due to proprietary restrictions, using this thesis as a design guide for new experiments should yield favorable results when applied to new tank designs. If the reader has any questions or would like an updated design process, the author’s preferred contact information can be found using the Orcid iD: 0000-0002-2617-2957 .
24
Amanowicz, Michel. "Etude des propriétés de transport galvanomagnétique de composés de neptunium et de plutonium." Université Joseph Fourier (Grenoble), 1995. http://www.theses.fr/1995GRE10038.
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Cette these presente une etude par des mesures galvanomagnetiques (resistivite, magnetoresistance, effet hall) des proprietes de transport electrique des monopnictures et monochalcogenures de neptunium (de structure nacl), de la solution solide pusb(1-x)te(x), et du compose intermetallique nppt3. Pour une meilleure comprehension des phenomenes physiques nos mesures sont discutees en etroite association avec les resultats obtenus par la diffraction des neutrons, l'aimantation et la spectroscopie mossbauer. L'etablissement de l'ordre antiferromagnetique triple-k de type i pour les monopnictures npas, npsb et npbi induit l'ouverture d'un gap dans la surface de fermi qui fait brusquement chuter le nombre de porteurs de charge et se traduit par une brutale augmentation de la resistivite. Dans le cas de npbi qui a la plus faible resistivite a temperature ambiante, l'ouverture du gap est si importante que ce compose devient semiconducteur. Il n'est pas aise de trancher de maniere definitive sur la nature du transport electrique des monochalcogenures de neptunium, il apparait cependant de maniere claire que ces composes sont des semi-metaux a temperature ambiante tandis qu'a basse temperature un caractere semiconducteur devient preponderant dans le cas de nps, alors que npte tendrait plutot vers un comportement metallique. Dans le cas de la solution solide pusb(1-x)te(x), il apparait que l'addition du tellure n'est pas simplement une dilution continue de pute non magnetique dans pusb, mais implique des changements fondamentaux dans les mecanismes d'echange induits par le changement de la concentration en electron. Le comportement kondo est present qu'elle que soit la concentration en tellure. Pour le compose nppt3 nous avons pu etablir son diagramme de phase magnetique a l'aide de mesures de resistivite sous champ magnetique et de fixer la temperature d'ordre antiferromagnetique t#n=30 k
25
Desmaele, Elsa. "Propriétés physico-chimiques des carbonates fondus par simulations atomistiques." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066316/document.
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L’étude des carbonates fondus présente un enjeu double : fondamental et appliqué. La description systématique de leurs propriétés physico-chimiques sur des gammes étendues de conditions thermodynamiques et de compositions chimiques est important pour le développement de leurs applications technologiques, ainsi que pour la compréhension de certains processus géochimiques. Afin de modéliser les carbonates fondus par simulations atomistiques, nous avons développé un champ de force classique en nous basant sur les données expérimentales disponibles dans la littérature et sur les structures microscopiques issues de simulations de dynamique moléculaire ab initio que nous avons réalisées. En utilisant ce champ de force dans des simulations de dynamique moléculaire, nous avons évalué les propriétés thermodynamiques (équation d’état, tension de surface à pression atmosphérique), la structure microscopique du liquide et les propriétés de transport (coefficients de diffusion, conductivité électrique, viscosité) d’un ensemble de carbonates fondus (Li2CO3, Na2 CO3 , K2 CO3, MgCO3 , CaCO3 et nombre de leurs mélanges) de leur point de fusion jusqu’aux conditions thermodynamiques du manteau terrestre. Nos résultats sont en très bon accord avec les données de la littérature. À notre connaissance, un modèle moléculaire des carbonates fondus couvrant un aussi large domaine de conditions thermodynamiques, de compositions chimiques et de propriétés physico-chimiques n’a encore jamais été publié. Sur la base de ce modèle, nous discutons aussi quelques propriétés des carbonates fondus à l’interface avec une phase gazeuse (gaz rares) : tension de surface et solubilité du gazBecause of their remarkable physicochemical properties carbonate melts receive an increasing interest in both fundamental and applied fields. Having a clear picture of their properties over a large range of thermodynamic conditions and chemical compositions is important for developing technological devices (e.g. fuel cell technology) and for providing a better understanding of a number of geochemical processes (e.g. role of molten carbonates in the geodynamics of the Earth’s mantle). To model molten carbonates by atomistic simulations, we have developed an optimized clas- sical force field based on experimental data available in the litterature and liquid structure data obtained from ab initio molecular dynamics simulations that we have performed. In implementing this force field into a molecular dynamics simulation code, we have evaluated the thermodynamics (equation of state, surface tension at atmospheric pressure), the microscopic liquid structure and the transport properties (diffusion coefficients, electrical conductivity and viscosity) of a set of molten carbonates (Li2CO3 , Na2 CO3, K2 CO3 , MgCO3, CaCO3 and many of their mixtures) from their melting point to the thermodynamic conditions of the Earth’s upper mantle. Our results are in very good agreement with the data available in the literature. To our knowledge a molecular model for molten carbonates covering such a large domain of thermodynamic conditions, chemical compositions and physico-chemical properties has never been published yet. Based on this model we also discuss some results on molten carbonates at the interface with a vapor phase (noble gases) : surface tension and gas solubility
26
Zeghib, Abdelhakim. "Contribution à l'étude de phénomènes de transport dans les couches minces Ni-Ag amorphes et microcristallisées." Rouen, 1987. http://www.theses.fr/1987ROUES014.
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Extension du modèle de Ziman aux alliages Ni-Ag et interprétation qualitative du comportement de la résistivité et du coefficient de température en fonction de la composition atomique d'argent. Etude de la structure de bandes de Ni-Ag à partir de mesures magnétiques. Mise en évidence d'un niveau lié virtuel dans les alliages majoritaires en argent, par la technique des plasmons de surface
27
Neyt, Jean-Claude. "Calcul de la tension interfaciale de mélanges gaz / eau, gaz / huile et huile / eau par simulation moléculaire." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00962483.
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La prédiction de valeurs de tension interfaciale des fluides est capitale dans de nombreuses applications industrielles. Les techniques de simulation moléculaire et l'évolution rapide des moyens de calcul intensif permettent depuis quelques années de prédire des valeurs de tension interfaciale pour des systèmes complexes. Des travaux concernant des équilibres liquide / vapeur des corps purs SO2, O2, N2 et Ar montrent que les modèles choisi pour chaque molécule peuvent influencer la qualité des prédictions de tension interfaciale. Des simulations d'équilibres gaz acide / alcane de type CO2 / n-butane, CO2 / n-décane et H2S / n-pentane ont ensuite été réalisées. Elles ont mis en évidence l'efficacité des méthodes de simulation de type Monte Carlo pour la prédiction des tensions interfaciales pour de tels systèmes. L'étude de systèmes ternaires H2O / N2+CH4 et H2O / CO2+H2S a par ailleurs montré que le recourt à la dynamique moléculaire pouvait faciliter l'équilibration des systèmes simulés, rendant plus efficace la prédiction des tensions interfaciales. L'étude d'équilibres liquide / vapeur de saumures de chlorure de sodium a permis de mettre en évidence l'efficacité de certains potentiels non-polarisables pour la prédiction de l'évolution de la tension interfaciale avec la molarité de sel. Les modèles polarisables de type core-shell choisis ne permettent de prédire ni les masses volumiques, ni les tensions interfaciales. Enfin, l'étude d'équilibres eau / alcane en présence de sel ou de méthanol a montré que les méthodes de dynamique moléculaire permettaient de prédire quantitativement des valeurs de tension interfaciale pour ce type d'interface. L'effet de l'alcool abaissant la tension interfaciale a bien été observé, tout comme son placement préférentiel à l'interface.
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Maitre, Emmanuel. "Sur une classe d'équations à double non linéarité : application à la simulation numérique d'un écoulement visqueux compressible." Phd thesis, Université Joseph Fourier (Grenoble), 1997. http://tel.archives-ouvertes.fr/tel-00004955.
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L'origine de ce travail est l'étude d'un problème industriel sur la mise en forme des thermoplastiques par injection. Nous nous sommes concentrés sur la partie remplissage du moule et sur la détermination de la position du front du polymère. Le travail présenté dans cette thèse comprend donc deux parties: => L'étude mathématique et numérique de l'équation en pression qui régit l'écoulement du polymère fondu. A partir de cet exemple nous avons mis en évidence et étudié une famille nouvelle d'équations à double non linéarité. => La détermination de l'interface polymère-air par des méthodes de suivi de lignes de niveau, l'interface étant décrite comme la ligne de niveau zéro d'une inconnue auxiliaire, que nous devons calculer. Nous avons obtenu l'existence d'une solution à l'équation de transport linéaire avec conditions aux limites à laquelle satisfait cette nouvelle inconnue. Puis nous avons mis au point une méthode numérique pour le calcul de l'interface polymère/air, en résolvant par éléments finis / volumes finis l'équation en pression et l'équation de transport du front. Notre méthode présente l'avantage d'une mise en oeuvre relativement aisée, robuste car elle permet de gérer les changements de topologie du front.
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Caniparoli, Jean-Philippe. "Etude par resonance magnetique nucleaire des conformations et des interactions moleculaires dans les mesophases lyotropes : application a des problemes de solubilisation." Paris 6, 1988. http://www.theses.fr/1988PA066117.
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Etude par rmn, de l'ordre et de la dynamique moleculaire des phases lyotropes de systemes binaires agent de surface a double chaine/eau: parametres d'ordre eleves, probabilites conformationelles, temps de correlation des mouvements moleculaires tres anisotropes en fonction de la tete polaire (phosphate ou ammonium); faible influence de la longueur de la chaine. Etude de l'ordre et de la dynamique de petites molecules en solution dans le systeme dibutylphosphate de sodium/eau en phase lamellaire: influence importante du caractere hydrophile ou hydrophobe du solute. Localisation des solutes non complexants dans le cristal liquide d'apres la relaxation induite par un ion paramagnetique
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He, Guo-Yuan, and 何國源. "Plasma Surface Modification of Parylene Using to Liquid Transport." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/64831269998965885976.
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碩士淡江大學
機械與機電工程學系碩士班
96
In this research, three materials (parylene, PDMS and glass) surface modification with three gases (CF4. SF6 and O2) plasma was presented. The lightly hydrophilic parylene can be transferred to hydrophobic parylene by CF4 and SF6 plasmas, whereas the hydrophobic PDMS was transferred to lightly hydrophilic PDMS by CF4 and SF6 plasmas. Moreover, the CF4 and SF6 plasmas can’t affect the hydrophilic property of glass (SiO2). On the contrary, the O2 plasma can transfer three materials to great hydrophilic parylene. In future, the three modified materials can be used in more other applications, for examples of self-cleaning and suction of fluids. Our research also successfully transported droplet by arrowed micro-structured surface ratchets with hydrophobic parylene or HMDS. The droplets would be transported more easily after the hydrophobic degree of surface ratchets was increased by hydrophobic parylene. The droplet can be up or back transported by advancing or recessive arrowed surface ratchets, and the average velocity is around 20 mm/sec. Discussion about design of the arrowed surface ratchets was also obtained by mathematical model of surface energy. It was proved that the parylene surface modification was using to the application of droplet transport.
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Chen, Ju-chin, and 陳儒瑾. "Studies of binary liquid crystal alignments using photo-alignment on polymer surface and their application." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/41608592096817723345.
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碩士國立成功大學
物理學系碩博士班
97
This study demonstrates the feasibility of binary liquid crystal (LC) alignments based on azo dye-doped liquid crystals (ADDLCs). The fabrication process is described as follows. Firstly, a monomer film is spin-coated onto a glass substrate with a homeotropic or homogeneous alignment layer. Secondly, an unpolarized UV-light is irradiated onto the substrate through a photo-mask having a desired pattern, and then, the UV-cured polymer-pattern is retained after removing the un-polymerized monomers by a suitable solvent (Acetone 80% and alcohol 20%). Finally, binary regions having polymer film/ homeotropic (or homogeneous) alignment layer are generated. Three devices, developed using this approach, are summarized as follows. (a) Polarization-independent and electrically switchable Fresnel lens: In this part, we use a Fresnel zone plate mask to fabricate the binary regions. Orthogonally hybrid alignments between two adjacent zones are achieved. The focusing efficiency is electrically switchable. The maximum focusing efficiency of the fabricated ADDLC Fresnel lens is ~34.14%, which is much higher than that of the used Fresnel zone plate mask (~ 25.6%). (b) Liquid crystal grating: In this part, a binary LC structures are fabricated using 50 �慆 grating mask. A LC grating with homeotropic and homogeneous alignments between two adjacent zones is achieved. The results show that the first order diffraction efficiency of this grating is electrically switchable, and the maximum diffraction efficiency of the first order is about 26.98%. Additionally, the binary structures can be optically switched to another binary LC structures - homeotropic and TN structures. (c) View-angle dependent LCD: Using binary LC structures, a LC cell having hybrid and homeotropic structures is fabricated. It is placed between two cross polarizers to form a LCD, which can display two different images by changing viewing angle. Additionally, the simulated transmittance contours of this LC display at different viewing angle obtained using the software of DIMOS consist with the experimental results.
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Lin, Chia-Wei, and 林佳緯. "The study in transport characteristics of binary LiTFSI-EMITFSIroom temperature ionic liquid electrolytes and a trace of additive for influencing property of secondary lithium battery." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/14339399307135756710.
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碩士雲林科技大學
化學工程與材料工程研究所
98
In this study, transport properties of the lithium bis(trifluoromethane sulfone)imide (LiTFSI)-EMITFSI binary room-temperature ionic liquid (RTIL) systems for lithium battery were measured with adapted temperature and composition. The phase diagram has been determined by Differential Scanning Calorimeter(DSC) and Thermogravimetric Analysis (TGA) . The electric conductivity and density of the binary melts were also be measured ,the results were be contributived to select the better compositions (LiTFSI-EMITFSI=20:80 mol%) of electrolyte for the Li-ion battery. With the same solute LiTFSI of binary system room temperature ionic liquid, the different solvent of conductivity the order of size is Formamide > Acetamide > Propionamide ≒ Urea > EMITFSI, the density order of size is EMITFSI > Urea > Formamide > Acetamide > Propionamide, based on the differences between the molecular structure, regardless of whether the carbon chain or increase、bond energies 、increase of NH2 or structural hindered, cause the molecular between solute - solvent interaction have changed. The cathodic lithium cobalt oxide film with layer structure was deposited by ratio frequency magnetron sputtering. LiCoO2 films prepared at 10mtorr and annealing temperature of 800oC.The addition of small amount of the binary LiTFSI-EMITFSI room temperature ionic liquid electrolytes in the commercial electrolyte (1M LiPF6 in EC/DEC (1:1 in vol.)). LiCoO2︱commercial electrolyte/RTIL︱Li coin cell were fabricated in a glove-box filled with argon environment. The addition of small amount of the room temperature ionic liquid (LiTFSI-EMITFSI 20:80 mol%) has higher capacity (121.45mAh/g) and lower capacity lost(27.11%).
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Xu, Yu-Yun, and 徐郁筠. "The Lateral Cooling Effect of the Side Wall with Slanted Surface on the Development of Double-diffusive Convection during the Solidification of a Liquid Binary Alloy." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/jrw9u3.
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碩士國立臺北科技大學
能源與冷凍空調工程系碩士班
97
Phase change materials were employed in industrial applications very often. The solidification of a binary solution is one of them (for example, casting of binary alloys). In the past, one of the main issues to study the solidification of a liquid binary alloy focused on the development of “double-diffusive convection” because it is the main reason to cause the poor quality of alloys. The objective of this study is to investigate the effect of the slope of the side wall on the development of double-diffusive convection. An aqueous solution of 27 wt.% NH4Cl, with a liquidus temperature corresponding to 18.9℃, was adopted as the test sample in this study and it was put into an enclosure cooled from the lateral side to investigate the flow field, heat and mass transport phenomena during solidification. Experiments conducted in this study include PIV measurement on the flow field, flow visualization by shadowgraph technique, measurement of the growth of the mushy zone with time, transient temperature distribution within the test cell and the concentration distribution within the cavity. According to the experimental results of PIV measurement and flow visualization by shadowgraph, the development of double-diffusive convection became stable at later stage of solidification. Four kinds of slopes of the side wall were employed in this study, including 0, 5, 10 and 15 degrees. The larger the slope is, the earlier the double-diffusive convection occurred among the slopes of 0, 5 and 10 degrees. However, the double-diffusive convection grew the slowest for the slope of 15 degrees.
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Dubois, David. "Autocrine loop in the purinergic control of airway surface liquid volume : monitoring with a novel side-view imaging technique." Thèse, 2010. http://hdl.handle.net/1866/3809.
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La Fibrose Kystique (FK) est une maladie dégénérative qui entraine une dégénération des poumons dû au problème de clairance mucociliaire (CMC). Le volume de surface liquide (SL) couvrant les cellules pulmonaires est essentiel à la clairance de mucus et au combat contre les infections. Les nucléotides extracellulaires jouent un rôle important dans la CMC des voies aériennes, en modifiant le volume de la SL pulmonaire. Cependant, les mécanismes du relâchement de l’ATP et de leurs déplacements à travers la SL, restent inconnus. Des études ultérieures démontrent que l’exocytose d’ATP mécano-sensible et Ca2+-dépendant, dans les cellules A549, est amplifié par les actions synergétiques autocrine/paracrine des cellules avoisinantes. Nous avions comme but de confirmer la présence de la boucle purinergique dans plusieurs modèles de cellules épithéliales et de développer un système nous permettant d’observer directement la SL. Nous avons démontrés que la boucle purinergique est fonctionnelle dans les modèles de cellules épithéliales examinés, mis appart les cellules Calu-3. L’utilisation de modulateur de la signalisation purinergique nous a permis d’observer que le relâchement d’ATP ainsi que l’augmentation du [Ca2+]i suivant un stress hypotonique, sont modulés par le biais de cette boucle purinergique et des récepteurs P2Y. De plus, nous avons développé un système de microscopie qui permet d’observer les changements de volume de SL en temps réel. Notre système permet de contrôler la température et l’humidité de l’environnement où se trouvent les cellules, reproduisant l’environnement pulmonaire humain. Nous avons démontré que notre système peut identifier même les petits changements de volume de SL.Cystic Fibrosis (CF) patients suffer from respiratory problems associated with pulmonary infections and exacerbations, due to improper mucociliary clearance (MCC). The airway surface liquid (ASL) covering pulmonary epithelial cells plays a pivotal role in MCC and infection control. Extracellular nucleotides control MCC in airway epithelia by modulating ASL volume, ciliary beating and mucin secretion. The mechanism(s) of their release and dispersal within the ASL remain incompletely understood. Studies with A549 cells, a human alveolar type II cell model, have shown that mechanosensitive, Ca2+-dependent ATP secretion is strongly amplified by the synergistic autocrine/paracrine actions of released nucleotides. The aim of this study was to examine whether the autocrine purinergic loop operates in different lung epithelial cell models and to develop an imaging system allowing the direct monitoring of ASL height during purinergic stimulation. We demonstrated that the signaling loop is functional in all epithelial cells tested, with the exception of Calu-3 epithelial cells. With different purinergic signaling modulators, we demonstrated that ATP release and [Ca2+]i elevations evoked by hypotonic stress were strongly amplified by autocrine/paracrine effects in cells expressing the P2Y receptor family. To monitor ASL volume changes in real time, we developed a novel epi-fluorescence, side-view microscopy system to observe ASL height. During experiments, cell cultures grown on permeable filters were mounted in a custom-designed chamber that allows control of the temperature, humidity and air flow above the cell monolayer, mimicking the pulmonary environment. This system detects even small changes in ASL volume following purinergic stimulation.