Готові списки джерел за темами / Air-water interface dynamics

Добірка наукової літератури з теми "Air-water interface dynamics"

Автор: Grafiati
Опубліковано: 6 вересня 2023

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Зміст

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Air-water interface dynamics".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "Air-water interface dynamics"

1

Wick, Collin D. "NaCl Dissociation Dynamics at the Air−Water Interface." Journal of Physical Chemistry C 113, no. 6 (January 21, 2009): 2497–502. http://dx.doi.org/10.1021/jp807901j.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Liu, Pu, Edward Harder, and B. J. Berne. "Hydrogen-Bond Dynamics in the Air−Water Interface." Journal of Physical Chemistry B 109, no. 7 (February 2005): 2949–55. http://dx.doi.org/10.1021/jp046807l.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Segur, Harvey, and Soroush Khadem. "Wind-Driven Waves on the Air-Water Interface." Fluids 6, no. 3 (March 16, 2021): 122. http://dx.doi.org/10.3390/fluids6030122.

Повний текст джерела
Анотація:
An ocean swell refers to a train of periodic or nearly periodic waves. The wave train can propagate on the free surface of a body of water over very long distances. A great deal of the current study in the dynamics of water waves is focused on ocean swells. These swells are typically created initially in the neighborhood of an ocean storm, and then the swell propagates away from the storm in all directions. We consider a different kind of wave, called seas, which are created by and driven entirely by wind. These waves typically have no periodicity, and can rise and fall with changes in the wind. Specifically, this is a two-fluid problem, with air above a moveable interface, and water below it. We focus on the local dynamics at the air-water interface. Various properties at this locality have implications on the waves as a whole, such as pressure differentials and velocity profiles. The following analysis provides insight into the dynamics of seas, and some of the features of these intriguing waves, including a process known as white-capping.
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Zimdars, David, Jerry I. Dadap, Kenneth B. Eisenthal, and Tony F. Heinz. "Femtosecond dynamics of solvation at the air/water interface." Chemical Physics Letters 301, no. 1-2 (February 1999): 112–20. http://dx.doi.org/10.1016/s0009-2614(99)00017-2.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Martynowycz, Michael, Andrey Ivankin, and David Gidalevitz. "Dynamics of Bilayer Interactions at the Air-Water Interface." Biophysical Journal 106, no. 2 (January 2014): 512a. http://dx.doi.org/10.1016/j.bpj.2013.11.2862.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Bhattacharya, R., and J. K. Basu. "Microscopic dynamics of nanoparticle monolayers at air–water interface." Journal of Colloid and Interface Science 396 (April 2013): 69–74. http://dx.doi.org/10.1016/j.jcis.2013.01.003.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Theodoratou, Antigoni, Ulrich Jonas, Benoit Loppinet, Thomas Geue, René Stangenberg, Dan Li, Rüdiger Berger, and Dimitris Vlassopoulos. "Photoswitching the mechanical properties in Langmuir layers of semifluorinated alkyl-azobenzenes at the air–water interface." Physical Chemistry Chemical Physics 17, no. 43 (2015): 28844–52. http://dx.doi.org/10.1039/c5cp04242a.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Zhang, Zhe, and Xiaoyu Song. "Nanoscale soil-water retention curve of unsaturated clay via molecular dynamics." E3S Web of Conferences 382 (2023): 10007. http://dx.doi.org/10.1051/e3sconf/202338210007.

Повний текст джерела
Анотація:
This paper characterizes nanoscale soil-water retention mechanism of unsaturated clay through molecular dynamics simulation. Series of molecular dynamics simulations of clay at low degrees of saturation were conducted. Soil water was represented by a point cloud through the centre-of-massmethod. Water-air interface area was measured numerically by the alpha shape method. Spatial variation of water number density is characterized and used to determine the adsorbed water layer. The soil-water retention mechanism at the nanoscale was analysed by distinguishing adsorptive pressure and capillary pressure at different mass water contents and considering apparent interface area (water-air interface area per unit water volume).
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Benderskii, Alexander V., and Kenneth B. Eisenthal. "Aqueous Solvation Dynamics at the Anionic Surfactant Air/Water Interface†." Journal of Physical Chemistry B 105, no. 28 (July 2001): 6698–703. http://dx.doi.org/10.1021/jp010401g.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Donovan, Michael A., Yeneneh Y. Yimer, Jim Pfaendtner, Ellen H. G. Backus, Mischa Bonn, and Tobias Weidner. "Ultrafast Reorientational Dynamics of Leucine at the Air–Water Interface." Journal of the American Chemical Society 138, no. 16 (April 18, 2016): 5226–29. http://dx.doi.org/10.1021/jacs.6b01878.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Дисертації з теми "Air-water interface dynamics"

1

Peace, Stella Kirsten. "Organisation and dynamics of amphiphilic systems at the air-water interface." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5389/.

Повний текст джерела
Анотація:
The behaviour of polymeric amphiphiles, specifically systems containing poly( methyl methacrylate), PMMA, and poly(ethylene oxide), PEO, spread at the air water interface is reported. An amphiphilic graft copolymer containing a PMMA backbone and PEO side chains forms the main subject of the study. Films of PMMA spread onto a 0.1 wt.% solution of PEO have also been considered. Due to the presence of a surface excess, both PEO and PMMA populate the surface and the latter system provides a model of the graft copolymer. Monolayer behaviour has been characterised by recording surface pressure isotherms. It has been demonstrated that the behaviour of the graft copolymers is highly composition dependent, exhibiting characteristics associated with the constituent homopolymers. In contrast the surface pressure isotherm for PMMA on PEO solution is quite unlike that for PMMA on water. Details of the structural organisation in these systems have been determined using neutron reflectometry. The surface organisation adopted by the graft copolymers varies as the surface concentration increases. The PEO side chains penetrate the subphase and stretch increasingly whereas the PMMA backbone behaves much like the homopolymer. This is in contrast to the behaviour of PMMA on PEO solution where the PMMA occupies a wider region of the interface. The structure of the adsorbed PEO differs from that of the bare solution but maintains a constant surface excess. Dynamic behaviour has been studied using surface quasi elastic light scattering. For the graft copolymers surface wave evolution is very unusual. The dilational parameters provide evidence, e.g. a negative dilational viscosity, indicating that surface wave propagation is complex and not described fully by current theories. Similar behaviour is exhibited by PMMA on a PEO solution. These features are believed to be associated with subphase penetration and are discussed in this context.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Sarica, Jordan. "Organisation and dynamics of a polymeric surfactant at the air-water interface." Thesis, Durham University, 2003. http://etheses.dur.ac.uk/3714/.

Повний текст джерела
Анотація:
Polyethylene(oxide) (PEO) is an intriguing polymer, it is water-soluble but exhibits surface-active properties. When capped hydrophobically at one end by a fluorocarbon group, a novel polymeric surfactant is generated. This has been synthesised by combining anionic polymerisation and an end-capping reaction using isophorone diisocyanate. Three molecular weight polymers were generated, for each of which a hydrogenous and a deuterated version were required, hi aqueous solution, these polymeric surfactants formed surface excess layers at the air-water interface and their surface organisation and dynamic behaviour has been investigated. Surface tension data was obtained using a digital tensiometer and the surface tension isotherm is dependent on both solution concentration and polymer molecular weight. Using neutron reflectometry, the organisation of such adsorbed polymer films at the air-water interface has been obtained over a range of solution concentrations for each polymer molecular weight. Neutron reflectometry data was analysed by both optical matrix and kinematic approximation methods. Both analyses yield the same description, i.e. a two-layer organisation is observed at the air-water interface for all three molecular weight polymers. The PEO layer thickness and the surface organisation are found to be dependent on both solution concentration and molecular weight. The PEO chains are totally immersed in the subphase and strongly anchored at the surface via the fluorocarbon end group. The dynamic behaviour of each PEO adsorbed surface excess at the air-water interface has been studied using surface quasi-elastic light scattering. A resonance between the capillary and dilational waves is observed and the maximum in damping is independent on surface organisation but is molecular weight and solution concentration dependent. The viscoelastic behaviour of the dilational modulus can be described using a simple Maxwell fluid model, from which a relaxation time has been obtained assuming a single relaxational process.
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Villa, Stefano. "Behaviour of a Colloid close to an Air-Water Interface : Interactions and Dynamics." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS074/document.

Повний текст джерела
Анотація:
Malgré un rôle important en physique, biologie et dans les processus industriels tels l’agroalimentaire et la dépollution de l’eau, la dynamique d'une particule colloïdale à proximité d'une interface fluide et ses interactions avec l’interface sont des phénomènes physiques encore débattus.Dans cette thèse, nous explorons la dynamique et l'interaction de particules colloïdales individuelles à proximité d'une interface air-eau à l’équilibre thermique.Afin de mener cette étude sans perturber le système expérimental, nous avons conçu et construit un microscope interférentiel à double onde adapté à l'interface air-eau. Contrairement à d'autres techniques expérimentales, notre configuration permet la mesure précise de la distance absolue entre particule l'interface sans nécessiter d’étalonnage ou d’hypothèse sur l'emplacement de l'interface. Nous avons ainsi pu obtenir des trajectoires hautement résolues de particules en 3D proches de l'interface, permettant la mesure précise des diffusions proche de l’interface et des interactions particules-interface.Le système montre deux profils d’énergie potentielle différents. Deux distances d’équilibre particule-interface sont ainsi observées. La plus grande peut être expliquée par la compétition des interactions de Van der Waals et électrostatiques avec la pesanteur. La distance d’équilibre plus courte ne peut s’expliquer que par la présence d’une interaction attractive supplémentaire. Les origines possibles de cette interaction sont discutées.En utilisant une nouvelle méthode d'analyse des déplacements quadratiques moyens des particules dans un potentiel générique, nous avons pu accéder aux coefficients de friction visqueuse des particules en fonction de la distance à l'interface. De manière singulière, l’interface air-eau se comporte comme une paroi liquide pour le mouvement des particules parallèlement à l’interface et comme une paroi solide pour le mouvement des particules perpendiculaire à l’interface. Ce résultat expérimental peut être partiellement rationalisé en considérant des modèles récents basés sur l’incompressibilité de surface. Cependant, certaines différences entre les expériences et les théories demeurent. Les coefficients de friction visqueuse sont plus importants que les prédictions hydrodynamiques et dépendent de la charge électrique des particules, ce qui suggère un possible rôle des phénomènes électrocinétiques.Enfin, le piégeage des particules à l'interface air-eau et leur angle de contact ont été mesurés tout en modifiant la force ionique de la solution aqueuse et en faisant varier l‘état de surface des colloïdes
Despite the relevance to environmental, biological and industrial processes, the motion of a colloidal particle close to a fluid interface and the way it interacts with the water surface are still largely elusive and intriguing physical phenomena.In this thesis, we explore the motion dynamics and the interaction of individual colloidal particles close to an air-water interface in thermal equilibrium.In order to investigate them without perturbing or altering the experimental system, we designed and built a dual-wave reflection interference microscope working with an air-water interface geometry. Contrary to other established experimental techniques, our set-up allows accurate measurements of the absolute particle-interface distance and thus does not require any calibration or assumption to know the location of the interface. Highly resolved 3D particle trajectories close to the interface were obtained, from which information on particle diffusion close to the interface and particle-interface interactions are obtained.The system shows two different potential energy landscapes resulting in two different equilibrium particle-interface distances. The larger one can be fairly explained by Van der Waals and electrostatic interactions combined with gravity. The shorter one highlights the existence of an unexpected additional attractive interaction. The possible origins of such an interaction are discussed.Using a method of analysis of the particle mean square displacements in a generic potential we developed, we were able to access to particle drag coefficients as a function of the distance from the interface. Peculiarly, the air-water interface acts as a slip boundary for the particle motion parallel to the interface and as a no-slip boundary for the particle motion perpendicular to the interface. This experimental result can be partially rationalized considering recent models based on surface incompressibility. However, some discrepancies between experiments and theories remain. Experimental drag coefficients are larger than the hydrodynamic predictions and depend on the particle electrical charge, pointing therefore to a possible role of electrokinetic phenomena.Finally, the particle trapping at the air-water interface and its contact angle were observed while tuning the ionic strength of the aqueous solution and varying the surface state of the colloids
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Rochford, Brian R. "Organisation and dynamics of an amphiphilic block copolymer at the air/water interface." Thesis, Durham University, 1995. http://etheses.dur.ac.uk/5415/.

Повний текст джерела
Анотація:
This thesis describes the techniques of anionic polymerisation and characterisation used in the synthesis of poly(methyl methacrylate)/poly(ethylene oxide) diblock copolymers, the various surface techniques used to examine the interfacial properties of these copolymers spread on water, and the dynamics of these copolymers in solution. The surface techniques used were surface pressure-concentration isotherm studies, neutron reflectivity, surface quasi-elastic light scattering, and ellipsometry. The thermodynamics of micellization and dynamic properties of the copolymer solutions were investigated using light scattering. The diblock copolymers had a target composition of 50:50 mole ratio and M(_W) = 50000. In addition, several copolymers had one or both blocks holly deuterated which was necessary for the neutron reflectivity studies where contrast variation was required to apply the kinematic approximation. Surface pressure isotherms give thermodynamic information about the behaviour of polymer segments at the interface. It has been possible to interpret this behaviour by using neutron reflectivity to obtain information concerning die thickness and distribution of the PMMA and PEO blocks, and water at the interface. The trends in layer thickness have been supported by the ellipsometric measurements and interpretation of the viscoelastic SQELS data has allowed conclusions about the hydrodynamics of the polymer chains at various surface concentrations.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Miller, Aline Fiona. "Organisation and dynamics of well-defined graft copolymers at the air-water interface." Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4226/.

Повний текст джерела
Анотація:
Novel amphiphilic graft copolymers with a backbone of poly(norbornene) (PNB) with poly(ethylene oxide) (PEO) grafts have been synthesised by a combination of ring opening metathesis and anionic polymerisation methods. The polymer has been prepared with hydrogenous and deuterated grafts and with grafts of different degrees of polymerisation. These graft copolymers spread at the air-water and air-PEO solution interface forming thin films and their organisation and dynamic behaviour is discussed. Monolayer behaviour was characterised from surface pressure isotherms and it was demonstrated that the shape of the isotherm is dependent on graft length and on the concentration of PEO in the subphase. Using neutron reflectometry the organisation of such spread films at the air-water interface have been obtained over a range of surface concentrations for each length of PEO graft. Data were analysed by both exact calculation methods and the partial kinematic approximation and the models adopted were verified by applying the model independent Bayesian analysis. All yield the same description i.e. the hydrophobic backbone remains at the uppermost surface while the PEO grafts penetrate the subphase. The PEO layer increases in thickness with increased surface concentration and graft length. In each case the rate of increase with surface concentration was initially rapid but above a critical concentration, a slower rate was observed. In this latter regime the variation of the tethered layer height scales with surface density (ơ) and degree of polymerisation of the graft (N) as, r(_s) = N(^1.06)ơ(^0.33),which agrees well with scaling and self consistent field theory of polymer brushes. The dynamic behaviour of each copolymer film spread on water has been studied using surface quasi-elastic light scattering. A resonance between the capillary and dilational waves is observed at identical surface concentrations for each copolymer film. The viscoelastic behaviour of the dilational mode is reminiscent of Kramers-Kronig relations. The phenomenon of resistive mode mixing was observed in frequency dependency studies.
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Zang, Duyang. "The dynamics of interfaces : rheology of silica nanoparticle monolayers at the air-water interface and dendritic growth in multicomponent alloys." Paris 11, 2009. http://www.theses.fr/2009PA112145.

Повний текст джерела
Анотація:
Cette thèse présente les deux sujets liés à la dynamique d'interfaces: la rhéologie des particules monocouches et de la croissance dendritique des alliages. Dans la première partie, chapitre1-6, les propriétés des monocouches de nanoparticules de silice à l’interface air-eau sont présentées et reliées à la stabilité des mousses faites avec les dispersions aqueuses de ces particules. Les propriétés des couches: évolution de texture, pression de surface, épaisseur, angle de contact des particules et concentration de surface sont caractérisées pour différentes hydrophobicités des particules. La viscoélasticité de compression des couches a été déterminée par trois méthodes basées sur l’utilisation de deux plaques de Wilhelmy dans des cuves Langmuir. Les différences remarquables entre les couches comprimées et les couches déposées ont été trouvés. Les modules présentent un maximum à l'hydrophobicité intermédiaire des particules et dépendent de la vitesse de déformation, de la quantité de particule initiale, de la longueur de la cuve et de l'âge de la couche. La viscoélasticité de cisaillement des couches a été également déterminée. Une analogie fréquence-gradient de vitesse a été trouvée comme chez d’autres solides mous tridimensionnels. La relaxation structurale s’effectue avec un temps de relaxation qui varie comme l’inverse du gradient de vitesse. Un comportement d'auto-guérison des fractures a été observé et lié à la relaxation structurale. Dans la deuxième partie, Chapitre 7, la croissance dendritique rapide d’alliages surfondus ternaires Ni-Co-Cu et quaternaires Ni-Co-Cu-Ge a été étudiée. La surfusion élevée est obtenue par lévitation électromagnétique et des méthodes de flux de verre. Les vitesses de croissance dendritiques ont été mesurées en fonction de la surfusion. Nous proposons une double fonction exponentielle pour décrire la relation entre la vitesse de croissance et la surfusion dans les alliages monophasiques. Un nouveau comportement a été observé : la vitesse de croissance des dendrites est abaissée en cas de séparation de phase et des mécanismes possibles sont proposés
This dissertation presents two topics related to the dynamics of interfaces: rheology of particle monolayers and the dendritic growth of alloys. In the first part, chapter1-6, the properties of silica nanoparticle monolayers at the air-water surface is presented and related to foam stability. The properties of the layers: textural evolution, surface pressure, thickness, particle contact angle with interface and effective surface concentration are characterized with respect to different particle hydrophobicities. The viscoelasticity of the layers are determined by three methods based on two Wilhelmy plates in the Langmuir trough. Remarkable differences between compressed layers and deposited layers have been found. The moduli present the maximum at intermediate particle hydrophobicity and depend on strain rate, initial particle quantity, trough length and age of the layer. The same universal linear and nonlinear behaviour as three-dimensional soft materials is found by a shear rheological study. The structural relaxation has been observed and the corresponding relaxation time has been characterized by SRFS method. A self-healing behavior is observed and a microscopic mechanism is proposed to account for the slow self-healing. The results suggests that the same physical process may involved in self heal as in structural relaxation. In the second part, chapter7, rapid dendritic growth in undercooled liquid ternary Ni-Co-Cu and quarternary Ni-Co-Cu-Ge alloys has been investigated. The high undercooling is obtained by electromagnetic levitation and glass flux methods. The dendritic growth velocities are measured as a function of undercooling. We propose a double exponential function to describe the relationship between growth velocity and undercooling in single phase alloys. A novel behavior that the dendritic growth velocity is reduced by liquid phase separation is found and the possible mechanism is proposed
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Andersen, Audrée. "Surfactant dynamics at interfaces : a series of second harmonic generation experiments." Phd thesis, Universität Potsdam, 2005. http://opus.kobv.de/ubp/volltexte/2006/655/.

Повний текст джерела
Анотація:
Adsorption layers of soluble surfactants enable and govern a variety of phenomena in surface and colloidal sciences, such as foams. The ability of a surfactant solution to form wet foam lamellae is governed by the surface dilatational rheology. Only systems having a non-vanishing imaginary part in their surface dilatational modulus, E, are able to form wet foams. The aim of this thesis is to illuminate the dissipative processes that give rise to the imaginary part of the modulus.

There are two controversial models discussed in the literature. The reorientation model assumes that the surfactants adsorb in two distinct states, differing in their orientation. This model is able to describe the frequency dependence of the modulus E. However, it assumes reorientation dynamics in the millisecond time regime. In order to assess this model, we designed a SHG pump-probe experiment that addresses the orientation dynamics. Results obtained reveal that the orientation dynamics occur in the picosecond time regime, being in strong contradiction with the two states model.

The second model regards the interface as an interphase. The adsorption layer consists of a topmost monolayer and an adjacent sublayer. The dissipative process is due to the molecular exchange between both layers. The assessment of this model required the design of an experiment that discriminates between the surface compositional term and the sublayer contribution. Such an experiment has been successfully designed and results on elastic and viscoelastic surfactant provided evidence for the correctness of the model.

Because of its inherent surface specificity, surface SHG is a powerful analytical tool that can be used to gain information on molecular dynamics and reorganization of soluble surfactants. They are central elements of both experiments. However, they impose several structural elements of the model system. During the course of this thesis, a proper model system has been identified and characterized. The combination of several linear and nonlinear optical techniques, allowed for a detailed picture of the interfacial architecture of these surfactants.
Amphiphile vereinen zwei gegensätzliche Strukturelemente in einem Molekül, eine hydrophile Kopfgruppe und ein hydrophobe, meist aliphatische Kette. Aufgrund der molekularen Asymmetrie erfolgt eine spontane Adsorption an der Wasser-Luft Grenzfläche. Die Adsorptionsschicht verändert die makroskopischen Eigenschaften des Materials, z.B. die Grenzflächenspannung wird erniedrigt. Amphiphile sind zentrale Bauelemente der Kolloid- und Grenzflächenforschung, die Phänomene, wie Schäume ermöglichen.

Eine Schaumlamelle besteht aus einem dünnen Wasserfilm, der durch zwei Adsorptionsschichten stabilisiert wird. Die Stabilität der Lamelle wird durch die Grenzflächenrheologie entscheidend geprägt. Die wesentliche makroskopische Größe in diesem Zusammenhang ist das so genannte Grenzflächendilatationsmodul E. Es beschreibt die Fähigkeit des Systems die Gleichgewichtsgrenzflächenspannung nach einer Expansion oder Dilatation der Adsorptionschicht wieder herzustellen. Das Modul E ist eine komplexe Größe, in dem der Imaginärteil direkt mit der Schaumstabilität korreliert.

Diese Arbeit widmet sich der Grenzflächenrheologie. In der Literatur werden zwei kontroverse Modelle zur Interpretation dieser Größe diskutiert. Diese Modelle werden experimentell in dieser Arbeit überprüft. Dies erfordert die Entwicklung neuer experimenteller Aufbauten basierend auf nichtlinearen, optischen Techniken. Mit diesen Experimenten konnte eines der Modelle bestätigt werden.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Lee, Woojin. "Structure and Dynamics of Polyhedral Oligomeric Silsesquioxane (POSS) and Poly(Ethylene Glycol) (PEG) Based Amphiphiles as Langmuir Monolayers at the Air/Water Interface." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26188.

Повний текст джерела
Анотація:
Throughout the study of polymeric Langmuir monolayers at the air/water (A/W) interface, the Wilhelmy plate and Langmuir-Blodgett (LB) techniques along with Brewster angle microscopy (BAM) have been identified as key methods for acquiring structural, thermodynamic, rheological and morphological information. These techniques along with surface light scattering (SLS), a method for probing a monolayerâ s dynamic dilational rheological properties, will be used to characterize homopolymers, poly(ethylene oxide) (PEO) and poly(ethylene glycol) (PEG), and a new class of novel polymeric surfactants, telechelic (POSS-PEG-POSS) and hemi-telechelic (POSS-PEG) polyhedral oligomeric silsesquioxane (POSS) derivatives of PEG. PEO with number average molar mass, Mn > ~ 18 kgâ ¢mol-1 form stable spread Langmuir films at the A/W interface, while oligomeric PEG have ï -A isotherms that deviate from high molar mass PEO. Nonetheless, SLS reveals that the dynamic dilational viscoelastic properties of any Mn PEG(PEO) only depend on ï and not Mn. Likewise, POSS-PEG-POSS telechelics exhibit molar mass dependent ï -A isotherms, where low ï regimes (ï < 1 mNâ ¢m-1) have PEG-like behavior, but high ï regimes were dominated by POSS-POSS interactions. SLS studies reveal that the dynamic dilational moduli of POSS-PEG-POSS are greater than either PEO or an analogous POSS compound, trisilanolcyclohexyl-POSS. The ability to control rheological properties and the hydrophilic-lipophilic balance even allows one POSS-PEG-POSS (PEG Mn = 1 kgâ ¢mol-1) to form Y-type LB-multilayer films. For POSS-PEG systems, comparisons at comparable POSS:PEG ratios reveal short PEG chains (PEG Mn ~ 0.5 kgâ ¢mol-1) yield similar viscoelastic properties as POSS-PEG-POSS (PEG Mn ~ 1 kgâ ¢mol-1), while longer PEG chains (PEG Mn ~ 2 kgâ ¢mol-1) yield lower modulus films than comparable POSS-PEG-POSS. These differences are attributed to brush-like PEG conformations in short POSS-PEG versus mushroom-like PEG conformations in long POSS-PEG at the A/W interface. These results provide insight for designing PEG-based amphiphilic nanoparticles with controlled interfacial rheology.
Ph. D.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Pezzotti, Simone. "DFT-MD simulations and theoretical SFG spectroscopy to characterize H-Bonded networks at aqueous interfaces : from hydrophobic to hydrophilic environments Structural definition of the BIL and DL: a new universal methodology to rationalize non-linear χ(2)(ω) SFG signals at charged interfaces, including χ(3)(ω) contributions What the Diffuse Layer (DL) Reveals in Non-Linear SFG Spectroscopy 2D H-Bond Network as the Topmost Skin to the Air-Water Interface Combining ab-initio and classical molecular dynamics simulations to unravel the structure of the 2D-HB-network at the air-water interface 2D-HB-Network at the air-water interface: A structural and dynamical characterization by means of ab initio and classical molecular dynamics simulations Spectroscopic BIL-SFG Invariance Hides the Chaotropic Effect of Protons at the Air-Water Interface Molecular hydrophobicity at a macroscopically hydrophilic surface Graph theory for automatic structural recognition in molecular dynamics simulations DFT-MD of the (110)-Co3O4 cobalt oxide semiconductor in contact with liquid water, preliminary chemical and physical insights into the electrochemical environment". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLE008.

Повний текст джерела
Анотація:
Améliorer notre connaissance de la structure de l'eau dans l'environnement spécial offert par une interface est essentiel pour la compréhension de nombreux phénomènes naturels et applications technologiques. Pour révéler cette structure interfaciale de l'eau, des techniques capables de fournir des informations microscopiques, de manière sélective, pour cette couche interfaciale (BIL) sont nécessaires. Dans le présent travail de thèse, nous avons donc étudié les interfaces aqueuses au niveau moléculaire, en couplant la modélisation théorique à partir de simulations DFT-MD avec les spectroscopies SFG et THz-IR. En développant de nouveaux protocoles/outils d'investigation associant simulations DFT-MD et spectroscopie SFG, en particulier pour la rationalisation plus complexe des interfaces chargées, nous avons fourni une compréhension globale de l'effet des conditions interfaciales d'hydrophilicité, de pH, de force ionique sur le réseau des liaisons-H formé dans la couche interfaciale BIL, sur ses signatures spectroscopiques et sur son impact sur les propriétés physico-chimiques. Nous avons montré pour la première fois que, dans des conditions suffisamment hydrophobes, l'eau interfaciale crée des réseaux des liaisons-H bidimensionnels, révélé expérimentalement par les spectres THz-IR. Le réseau-2D dicte la dynamique de l'eau interfaciale, le potentiel de surface, l'acidité de surface, la tension superficielle et la thermodynamique d'hydratation des solutés hydrophobes. Cet "ordre horizontal" aux interfaces hydrophobes est opposé à "l'ordre verticale" obtenu aux interfaces hydrophiles. Nous avons aussi révélé comment les ions et les conditions de pH modifient ces arrangements structuraux
Improving our knowledge on water H-Bonded networks formed in the special environment offered by an interface is pivotal for our understanding of many natural phenomena and technological applications. To reveal the interfacial water arrangement, techniques able to provide detailed microscopic information selectively for the interfacial layer are required. In the present thesis work, we have hence investigated aqueous interfaces at the molecular level, by coupling theoretical modeling from DFT-MD simulations with SFG & THz-IR spectroscopies. By developing new investigation protocols/tools, coupling DFT-MD simulations and SFG spectroscopy, in particular for the more complex rationalization of charged interfaces, we have provided a global comprehension of the effect of various interfacial conditions (hydrophilicity, pH, ionic strength) on the HB-Network formed in the interfacial layer (BIL), on its spectroscopic signatures and on its impact on physico-chemical properties. We have shown for the first time that, in sufficiently hydrophobic conditions, BIL interfacial water creates special 2-Dimensional HB-Networks, experimentally revealed by one specific THz-IR marker band. Such 2D-network dictates HBs and orientational dynamics of interfacial water, surface potential, surface acidity, water surface tension and thermodynamics of hydration of hydrophobic solutes. Such "horizontal ordering” of water at hydrophobic interfaces is found opposite to the “vertical ordering” of water at hydrophilic interfaces, while coexistence of the two orders leads to disordered interfacial water in intermediate hydrophilic/hydrophobic conditions. Both DFT-MD and SFG further revealed how ions & pH conditions alter these BIL-water orders
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Kölsch, Peter. "Static and dynamic properties of soluble surfactants at the air, water interface." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976726548.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Частини книг з теми "Air-water interface dynamics"

1

Tang, Fujie. "Definition of Free O–H Group at the Air–Water Interface." In Structures and Dynamics of Interfacial Water, 23–39. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-8965-8_3.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Panda, Amiya Kumar, and Kaushik Nag. "A Cursory Glance at the Phyiscochemical Properties of Oppositely Charged Surfactants in Solution and at the Air-Water Interface." In Structure and Dynamics of Membranous Interfaces, 385–415. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9780470388495.ch14.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Bussières, Sylvain, Julie Boucher, Philippe Desmeules, Michel Grandbois, Bernard Desbat, and Christian Salesse. "Monitoring of Membrane-Associated Protein Binding and of Enzyme Activity in Monolayers at the Air-Water Interface by Infrared Spectroscopy." In Structure and Dynamics of Membranous Interfaces, 165–89. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9780470388495.ch7.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Castro, A., D. Zhang, and K. B. Eisenthal. "Dynamics of Molecular Rotation at the Air/Water Interface by Time-Resolved Second-Harmonic Generation." In Ultrafast Phenomena VIII, 644–49. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-84910-7_209.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Münster, U., E. Heikkinen, and J. Knulst. "Nutrient composition, microbial biomass and activity at the air-water interface of small boreal forest lakes." In Eutrophication in Planktonic Ecosystems: Food Web Dynamics and Elemental Cycling, 261–70. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-1493-8_21.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Tang, Fujie. "Structure and Dynamics of the Ice-Air Interface." In Structures and Dynamics of Interfacial Water, 57–78. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-8965-8_5.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Hynes, Anthony J., Deanna L. Donohoue, Michael E. Goodsite, and Ian M. Hedgecock. "Our current understanding of major chemical and physical processes affecting mercury dynamics in the atmosphere and at the air-water/terrestrial interfaces." In Mercury Fate and Transport in the Global Atmosphere, 427–57. Boston, MA: Springer US, 2009. http://dx.doi.org/10.1007/978-0-387-93958-2_14.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Nagata, Y., E. H. G. Backus, and M. Bonn. "Dynamics of Water Molecules at the Water/Air Interface." In Encyclopedia of Interfacial Chemistry, 348–55. Elsevier, 2018. http://dx.doi.org/10.1016/b978-0-12-409547-2.13229-9.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

"The Dynamics of Formation and Structure of the Air–Water Interface in the Presence of Protein – Polysaccharide Mixtures." In Water Properties of Food, Pharmaceutical, and Biological Materials, 461–70. CRC Press, 2006. http://dx.doi.org/10.1201/9781420001181-31.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

"Turbulent Gas Transfer across Air–Water Interfaces." In Handbook of Environmental Fluid Dynamics, Volume One, 497–506. CRC Press, 2012. http://dx.doi.org/10.1201/b14241-44.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Air-water interface dynamics"

1

Li, Zhong, Rajeev K. Jaiman, and Boo Cheong Khoo. "Simulations of Air Cavity Dynamics During Water Entry and Slamming." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23635.

Повний текст джерела
Анотація:
An adaptive mesh refinement based Volume-of-Fluid (VOF) two-phase method has been employed to simulate the water entry and slamming problems of solid bodies with various geometries. The computations have been performed by using the GFS (Gerris Flow Solver) libraries. Solid boundaries or the interfaces between the solid and the fluid are tracked by a piece-wise linear volume-of-fluid method. The key ingredient in this simulation study is the capability of parallel adaptive refinement along the free-surface interface to capture the interface conditions accurately while using the Eulerian grid based VOF approach. The novelty of this work is that it is the first time to apply GFS libraries and adaptive VOF in solving complex water entry problems to the best of our knowledge. Before applying to a particular application, the adaptive VOF solver is validated by simulating the vertical water entry of a circular disk. The simulations of solid bodies with different geometries such as thin plates are then conducted to investigate the physics of air-cushioning effect during slamming.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Castro, Alonso, Dan Zhang, and K. B. Eisenthal. "Dynamics of Molecular Rotation at the Air/Water Interface by Time-Resolved Second Harmonic Generation." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/up.1992.thc30.

Повний текст джерела
Анотація:
To investigate orientational relaxation of molecules at the air/liquid interfaces we have used the technique of second harmonic generation as the probe. The idea of the experiment is to use a polarized picosecond pump pulse to preferentially excite molecules of a given orientation at the interface and thereby disturb the equilibrium orientational distribution. The relaxation of the perturbed distribution is monitored by the second harmonic signal generated by a time-delayed second laser pulse at the interface. Such surface second harmonic signal continues to change as the ground and excited molecules undergo rotation towards their equilibrium distributions and as the excited molecules relax back to the ground state.
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Choudhuri, Madhumita, and Alokmay Datta. "Long-timescale dynamics of thiol capped Au nanoparticle clusters at the air-water interface." In SOLID STATE PHYSICS: Proceedings of the 58th DAE Solid State Physics Symposium 2013. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4872797.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Eisenthal, Kenneth B. "Dynamics at Interfaces." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/up.1990.wb2.

Повний текст джерела
Анотація:
The dynamics of physical and chemical processes at the air/water interface using a picosecond pump and a second harmonic probe method will be described. The application of this method to photoisomerization, intermolecular electronic energy transfer and excited state proton transfer will be presented.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

La Foy, Roderick R., Sunghwan Jung, and Pavlos Vlachos. "Long Term Dynamics of Water-Entry Cavity." In ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting collocated with 8th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-31210.

Повний текст джерела
Анотація:
Many engineering applications involve the motion of objects crossing a fluid interface. The dynamics of this process are often complicated due to the interplay of surface tension, gravity, and inertia. Nevertheless, a simple analysis using potential flow theory works well to predict the interfacial profile of the air cavity formed during an impact. Most current theories however, cannot predict the behavior of the air cavity after pinch off occurs. We therefore investigated the long term dynamics of water entry in both experiment and theory. It was found that shortly after pinch off the cavity dynamics become governed primarily by thermodynamic gas relations. The internal pressure slowly rises due to the cavity volume decreasing while the ambient liquid pressure quickly increases as a result of the descent of the projectile. This effect is incorporated into our model to correctly predict the cavity geometry.
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Ahmed, Mohammed, Satoshi Nihonyanagi, and Tahei Tahara. "Ultrafast Vibrational Relaxation of Excited Free OD at the Air/Water Interface Revealed by Femtosecond Time-Resolved HD-VSFG spectroscopy." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/up.2022.tu1a.6.

Повний текст джерела
Анотація:
Femtosecond time-resolved HD-VSFG spectroscopy reveals ultrafast vibrational dynamics of free OD at the air/water interface. The absence of isotope dilution effect on the vibrational lifetime suggests that the excited free OD relaxes predominantly through the reorientation mechanism.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Raghavan, S. Sethu, and Raj M. Manglik. "Visualization of Micro-Scale Bubble Dynamics in Pure Liquids and Aqueous Surfactant Solutions." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56858.

Повний текст джерела
Анотація:
Growth and departure of a single adiabatic bubble in pure liquids and aqueous surfactant solutions is visualized. High-resolution photographic records are obtained that characterize the micro-scale bubble dynamics (shape, size, and post-departure translation), the mean bubble diameter at different time periods of its growth and departure, and the bubble surface age (the time interval from the newly formed interface to the attainment of departure diameter). This pre- and post-departure dynamics of air bubbles is visualized in water, N, N dimethyl-formamide (DMF), and ethyl alcohol (all pure liquids), and aqueous surfactant solutions of SDS (1250 wppm, 2500 wppm, and 5000 wppm), CTAB (200 wppm), and Triton X-305 (1000 wppm). The evolution of different bubble shapes, sizes, and departure frequencies is presented to highlight the effects of surface-active forces. In the case of surfactant solutions, the dynamic effects of the molecular-scale adsorption-desorption dynamics of the additive at the liquid-air interface that manifests in the dynamic surface tension is also delineated.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Arienti, M., and M. C. Soteriou. "Dynamics of Pulsed Jet in Crossflow." In ASME Turbo Expo 2007: Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-27816.

Повний текст джерела
Анотація:
We examine the effect of time-dependent forcing on jet-in-crossflow atomization in the case of pulsed liquid injection and uniform crossflow. The dynamics of the jet is captured by a numerical approach that blends interface tracking of the liquid surface with an empirical description of the atomization process. The unsteady Reynolds-Averaged Navier-Stokes equations for the gas and the continuous (i.e., preceding breakup) liquid phase are solved simultaneously with the Lagrangian equations for the droplet trajectories. This approach captures the near field transient due to the opening (closing) of the fuel valve, as well as the convective delay of the spray in the far field. Validation is carried out with Phase Doppler Interferometry (PDI) and Mie scattering measurements at standard conditions for pulsed jets of water and ethanol in crossflow air. The discussion is focused on the shape of the convecting spray pulse and on the trends due to variations in crossflow and jet velocities.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Mehdizadeh, A., S. A. Sherif, and W. E. Lear. "Numerical Simulation of Two-Phase Slug Flows in Microchannels." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88126.

Повний текст джерела
Анотація:
In this paper the Navier-stokes equations for a single liquid slug have been solved in order to predict the circulation patterns within the slug. Surface tension effects on the air-water interface have been investigated by solving the Young–Laplace equation. The calculated interface shape has been utilized to define the liquid slug geometry at the front and tail interfaces of the slug. Then the effects of the surface tension on the hydrodynamics of the two-phase slug flow have been compared to those where no surface tension forces exist. The importance of the complex flow field features in the vicinity of the two interfaces has been investigated by defining a non-dimensional form of the wall shear stress. The latter quantity has been formulated based on non-dimensional parameters in order to define a general Moody friction factor for typical two-phase slug flows in microchannels. Moreover, the hydrodynamics of slug flow formation has been examined using computational fluid dynamics (CFD). The volume-of-fluid (VOF) method has been applied to monitor the growth of the instability at the air-water interface. The lengths of the slugs have been correlated to the pressure fluctuations in the mixing region of the air and water streams at an axisymmetric T-junction. The main frequencies of the pressure fluctuations have been investigated using the Fast Fourier Transform (FFT) method.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Rahman, M. A., S. Butt, J. M. Alam, M. Shahwan, M. Hunt, and S. Imtiaz. "Experimental and Numerical Investigations of Bubble Dynamics in Porous and Non-Porous Media." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-42257.

Повний текст джерела
Анотація:
In this study an experimental work is conducted to investigate the shape and speed of an air bubble in a pipe filled with different viscous fluids and porous media. The experimental results are also compared with the Computational Fluid Dynamics (CFD) simulation. Multiphase flows are complex due to the infinitely deformable nature of interface in gas/liquid flows. If one of the phases is gas acts as dispersed phase in the form of bubble, then the complexity will arise from the non-uniform distribution of bubbles in the pipe cross-section and axial distance. Inclusion of different viscous fluids simulating the industrial scale hydrocarbon properties brings added challenge in understating the bubble rise, coalescence and breakup dynamics. Moreover, bubble rise and change of shape of bubble in porous media will bring additional complexity in the flow dynamics. The pipe used in the experiment and CFD was 11.6 cm ID and a length of 100 cm. Three situations were tested: i) an air bubble rising in stagnant water, ii) an air bubble rising in moving water, and iii) an air bubble rising in a stagnant water but filled with porous media with porosity of 27%. Preliminary CFD results indicate that an air bubble has an average velocity of 0.2468 m/s and 0.2524 m/s in stagnant water and moving water, respectively, which is very close to experimental results.
Стилі APA, Harvard, Vancouver, ISO та ін.
Також вас можуть зацікавити розширені добірки на тему "Air-water interface dynamics" для конкретних типів джерел:
Статті в журналах Дисертації
Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!

До бібліографії