ORCID Profile
0000-0001-5391-2618
Current Organisation
Max Planck Institute for Polymer Research
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Publisher: American Physical Society (APS)
Date: 09-12-2011
Publisher: Emerald
Date: 22-07-2019
DOI: 10.1108/APJML-08-2018-0334
Abstract: The purpose of this paper is to investigate and develop an integrated theoretical relationship by including destination image and attitudes into the quality-value-satisfaction-loyalty paradigm in the context of beach tourism. A personal-administered survey was conducted using a convenient s ling technique to collect data from 601 tourists who had visited popular beach destinations in Bangladesh. Then, the structural relationships between the factors likely to affect tourist attitudes and loyalty were examined. The findings reveal that both service quality and perceived values have a direct effect on destination image, tourist attitudes and satisfaction. Additionally, destination image and satisfaction significantly affect tourist attitudes and loyalty. The direct relationship of perceived service quality and perceived value with tourist loyalty was ignored in the model due to reporting consecutive indirect relationship between them in prior studies. These findings contribute to the extension of theoretical and managerial knowledge, especially in a beach tourism setting, where little research has been done to investigate the proposed relationships. The originality of this study lies in providing theoretical and empirical evidence regarding the effect of service quality and perceived value, especially on destination image and tourist attitude to behaviour in the loyalty model, which has been scarcely examined in the prior tourism literature.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C6SM02860H
Abstract: We provide an advanced understanding of the evaporation process of ouzo (multi-component) drops.
Publisher: American Physical Society (APS)
Date: 03-01-2013
Publisher: American Chemical Society (ACS)
Date: 03-03-2020
Publisher: American Chemical Society (ACS)
Date: 13-12-2022
Publisher: American Physical Society (APS)
Date: 10-05-2013
Publisher: American Physical Society (APS)
Date: 08-04-2003
Publisher: American Chemical Society (ACS)
Date: 21-12-2016
DOI: 10.1021/ACS.LANGMUIR.6B03792
Abstract: A water drop moving on a superhydrophobic surface or an oil drop moving on a superoleophobic surface dissipates energy by pinning/depinning at nano- and microprotrusions. Here, we calculate the work required to form, extend, and rupture capillary bridges between the protrusions and the drop. The energy dissipated at one protrusion W
Publisher: American Association for the Advancement of Science (AAAS)
Date: 17-01-2020
Abstract: We monitor the self-cleaning process on a single-particle level and quantify the involved forces.
Publisher: American Chemical Society (ACS)
Date: 12-07-2021
Publisher: American Chemical Society (ACS)
Date: 30-08-2019
Publisher: American Chemical Society (ACS)
Date: 16-09-2021
Publisher: IOP Publishing
Date: 19-02-2005
Publisher: Springer Science and Business Media LLC
Date: 29-01-2019
DOI: 10.1038/S41467-019-08385-W
Abstract: The assembly of colloidal particles from evaporating suspension drops is seen as a versatile route for the fabrication of supraparticles for various applications. However, drop contact line pining leads to uncontrolled shapes of the emerging supraparticles, hindering this technique. Here we report how the pinning problem can be overcome by self-lubrication. The colloidal particles are dispersed in ternary drops (water, ethanol, and anise-oil). As the ethanol evaporates, oil microdroplets form (‘ouzo effect’). The oil microdroplets coalesce and form an oil ring at the contact line, levitating the evaporating colloidal drop (‘self-lubrication’). Then the water evaporates, leaving behind a porous supraparticle, which easily detaches from the surface. The dispersed oil microdroplets act as templates, leading to multi-scale, fractal-like structures inside the supraparticle. Employing this method, we could produce a large number of supraparticles with tunable shapes and high porosity on hydrophobic surfaces.
Publisher: American Chemical Society (ACS)
Date: 11-09-2009
DOI: 10.1021/LA901414Y
Abstract: Atomic force microscopy was used to study the adsorption of the surfactant octadecyl trimethyl ammonium chloride (C18TAC) at a low concentration (0.03 mM) to negatively charged surfaces in water. Atomic force microscopy tips were functionalized with dimethyloctadecyl(3-tripropyl)ammonium chloride (C18TAC-si) or N-trimethoxysilylpropyl-N,N,N-trimethylammomium chloride (hydrophilpos-si) to facilitate imaging of the adsorbed surfactant without artifacts. Tapping mode images and force measurements revealed C18TAC patches, identified as partial surfactant bilayers or hemimicelles. The forces controlling the adsorption process of the C18TAC to a negatively charged surface were investigated by measuring the forces between a C18TAC-si or a hydrophilpos-si tip and a silica surface in the presence of varying concentrations of either NaCl or NaNO3. Screening of forces with an increasing NaCl concentration was observed for the C18TAC-si and hydrophilpos-si tips, proving an electrostatic contribution. Screening was also observed for the hydrophilpos-si tip in NaNO3, whereas a long-range attraction was observed for the C18TAC-si tip for all NaNO3 concentrations. These results indicate that screening of the forces for the C18TAC-si tip depended on the type and/or size of the anion, possibly due to a different probability of the anions to enter the silane layers. The interaction of C18TAC patches with C18TAC-si tips in the presence of NaCl and the interaction of the patches with hydrophilpos-si tips in either NaCl or NaNO3 were repulsive and independent of the number of force curves measured, indicating a stable, positively charged C18TAC patch. However, the forces measured between the patches and a C18TAC-si tip in NaNO3 depended on the number of force curves measured, indicating a change in patch structure induced by the first interaction.
Publisher: American Chemical Society (ACS)
Date: 21-05-2005
DOI: 10.1021/LA050226L
Abstract: The colloid probe technique was used to investigate the interactions between in idual zinc sulfide (ZnS) microspheres and an air bubble in electrolyte solution. Incorporation of zinc ions into the electrolyte solution overcomes the disproportionate zinc ion dissolution and mimics high-volume-fraction conditions common in flotation. Determined interaction forces revealed a distinct lack of long-ranged hydrophobic forces, indicated by the presence of a DLVO repulsion prior to particle engulfment. Single microsphere contact angles were determined from particle-bubble interactions. Contact angles increased with decreasing radii and with surface oxidation. Surface modification by the absorption of copper and subsequently potassium O-ethyldithiocarbonate (KED) reduced repulsive forces and strongly increased contact angles.
Publisher: IOP Publishing
Date: 10-10-2005
Publisher: Elsevier BV
Date: 09-2003
Publisher: AIP Publishing
Date: 04-10-2016
DOI: 10.1063/1.4963792
Abstract: Classical density functional theory is applied to investigate the validity of a phenomenological force-balance description of the stability of the Cassie state of liquids on substrates with nanoscale corrugation. A bulk free-energy functional of third order in local density is combined with a square-gradient term, describing the liquid-vapor interface. The bulk free energy is parameterized to reproduce the liquid density and the compressibility of water. The square-gradient term is adjusted to model the width of the water-vapor interface. The substrate is modeled by an external potential, based upon the Lennard-Jones interactions. The three-dimensional calculation focuses on substrates patterned with nanostripes and square-shaped nanopillars. Using both the force-balance relation and density-functional theory, we locate the Cassie-to-Wenzel transition as a function of the corrugation parameters. We demonstrate that the force-balance relation gives a qualitatively reasonable description of the transition even on the nanoscale. The force balance utilizes an effective contact angle between the fluid and the vertical wall of the corrugation to parameterize the impalement pressure. This effective angle is found to have values smaller than the Young contact angle. This observation corresponds to an impalement pressure that is smaller than the value predicted by macroscopic theory. Therefore, this effective angle embodies effects specific to nanoscopically corrugated surfaces, including the finite range of the liquid-solid potential (which has both repulsive and attractive parts), line tension, and the finite interface thickness. Consistently with this picture, both patterns (stripes and pillars) yield the same effective contact angles for large periods of corrugation.
Publisher: Royal Society of Chemistry (RSC)
Date: 2009
DOI: 10.1039/B812217B
Abstract: Well-ordered and uniform titania nanoparticle arrays were synthesized using diblock copolymers as structure directing agents. High molecular weight copolymers of polystyrene-b-polyethylene oxide and poly(methylmethacrylate)-b-polyethylene oxide were used to control the distance between titania nanoparticles in the range of 20-60 nm. Using these titania nanoparticle arrays and regioregular poly(3-hexylthiophene), models for a dye sensitized photovoltaic cell were assembled, in which the interparticle spacing was systematically varied. In these simplified solar cells, the titania nanocrystals were surrounded by a continuous regioregular poly(3-hexylthiophene) phase. The spacing between the titania nanoparticles was chosen as to provide enough space for the hole transfer material-regioregular poly(3-hexylthiophene)-to assemble as pi stacks. The external quantum efficiency showed a clear dependence on the distance between titania nanoparticles and reached 12% at an excitation wavelength of 515 nm in the best case. This demonstrates that the regioregular poly(3-hexylthiophene) phase acts as the locus of excition generation while the dye layer prevents charge recombination at the heterointerface. Thus control of the exciton diffusion is a key issue for present solid-state dye sensitized solar cells.
Publisher: Elsevier BV
Date: 06-2005
DOI: 10.1016/J.CIS.2004.08.003
Abstract: The essence of mineral flotation is the formation of strong particle-bubble aggregates. Hydrodynamics and DLVO forces hinder the particle-bubble approach, however the presence of a hydrophobic surface results in hydrophobic attraction and strong aggregate formation. In this article we review literature where the colloid probe technique has been used to investigate flotation, primarily particle-bubble interactions in aqueous solution. In some instance particles-bubble interactions have used to quantify the hydrophobic force, whilst hydrophobic forces are crucial for particle-bubble attachment, studies of hydrophobic forces are not the main focus of this article.
Publisher: Wiley
Date: 2023
DOI: 10.1002/DRO2.42
Abstract: The friction force opposing the onset of motion of a drop on a solid surface is typically considered to be a material property for a fixed drop volume on a given surface. However, here we show that even for a fixed drop volume, the static friction force can be tuned by over 30% by preshaping the drop. The static friction usually exceeds the kinetic friction that the drop experiences when moving in a steady state. Both forces converge when the drop is prestretched in the direction of motion or when the drop shows low contact angle hysteresis. In contrast to static friction, kinetic friction is independent of preshaping the drop, that is, the drop history. Kinetic friction forces reflect the material properties.
Publisher: Springer Science and Business Media LLC
Date: 06-11-2017
DOI: 10.1038/NPHYS4305
Location: Germany
No related grants have been discovered for Hans-Jürgen Butt.