Navegação Ciências Exatas e da Terra por Autor "Diehl, Alexandre"
Resultados 1-16 de 16
-
Charge regulation of colloidal particles : theory and simulations
(2019) [Artigo de periódico]To explore charge regulation (CR) in physicochemical and biophysical systems, we present a model of colloidal particles with sticky adsorption sites which account for the formation of covalent bonds between the hydronium ... -
Colloidal charge renormalization in suspensions containing multivalent electrolyte
(2010) [Artigo de periódico]A theory is proposed which allows us to self-consistently calculate the effective colloidal charge and the counterion and coion density profiles in suspensions containing both multivalent and monovalent electrolytes. The ... -
Colloidal charge reversal : dependence on the ionic size and the electrolyte concentration
(2008) [Artigo de periódico]Extensive Monte Carlo simulations and scaling arguments are used to study the colloidal charge reversal. The critical colloidal surface charge density σc at which the reversal first appears is found to depend strongly on ... -
Counterion correlations and attraction between like-charged macromolecules
(2001) [Artigo de periódico]A simple model is presented for the appearance of attraction between two like-charged polyions inside a polyelectrolyte solution. The polyions are modeled as rigid cylinders in a continuum dielectric solvent. The strong ... -
Diffusion enhancement in core-softened fluid confined in nanotubes
(2012) [Artigo de periódico]We study the effect of confinement in the dynamical behavior of a core-softened fluid. The fluid is modeled as a two length scales potential. This potential in the bulk reproduces the anomalous behavior observed in the ... -
Effective charge of colloidal particles
(2004) [Artigo de periódico]A new dynamical definition of the effective colloidal charge, especially suitable for the Monte Carlo and Molecular-dynamics simulations, is proposed. It is shown that for aqueous colloidal suspensions containing monovalent ... -
Electrostatic correlations in colloidal suspensions : density profiles and effective charges beyond the Poisson–Boltzmann theory
(2009) [Artigo de periódico]A theory is proposed which allows us to calculate the distribution of the multivalent counterions around a colloidal particle using the cell model. The results are compared with the Monte Carlo simulations and are found ... -
Enhanced flow of core-softened fluids through narrow nanotubes
(2014) [Artigo de periódico]We investigate through non-equilibrium molecular dynamic simulations the flow of anomalous fluids inside rigid nanotubes. Our results reveal an anomalous increase of the overall mass flux for nanotubes with sufficiently ... -
Interaction between random heterogeneously charged surfaces in an electrolyte solution
(2015) [Artigo de periódico]We study, using Monte Carlo simulations, the interaction between infinite heterogeneously charged surfaces inside an electrolyte solution. The surfaces are overall neutral with quenched charged domains. An average over the ... -
Ion fluxes through nanopores and transmembrane channels
(2012) [Artigo de periódico]We introduce an implicit solvent Molecular Dynamics approach for calculating ionic fluxes through narrow nanopores and transmembrane channels. The method relies on a dual-control-volume grand-canonical molecular dynamics ... -
Ions at the air-water interface : an end to a hundred-year-old mystery?
(2009) [Artigo de periódico]Availability of highly reactive halogen ions at the surface of aerosols has tremendous implications for the atmospheric chemistry. Yet neither simulations, experiments, nor existing theories are able to provide a fully ... -
Isothermal adsorption of polyampholytes on charged nanopatterned surfaces
(2019) [Artigo de periódico]We investigate the adsorption of neutral polyampholytes on charged nanopatterned surfaces. The surfaces have charged domains but are overall neutral. To perform efficient simulations, we use an approach which combines the ... -
Neutral polyampholyte in an ionic solution
(1996) [Artigo de periódico]The behavior of a neutral polyampholyte (PA) chain with N monomers, in an ionic solution, is analyzed in the framework of the full Debye-Hückel-Bjerrum-Flory (DHBjF) theory. A PA chain, that in addition to the neutral ... -
Sine-gordon mean field theory of a coulomb gas
(1997) [Artigo de periódico]Sine-Gordon field theory is used to investigate the phase diagram of a neutral Coulomb gas. A variational mean-field free energy is constructed and the corresponding phase diagrams in two and three dimensions are obtained. ... -
Smoluchowski equation and the colloidal charge reversal
(2006) [Artigo de periódico]Smoluchowski equation and the Monte Carlo simulations are used to study the conditions leading to the reversal of the electrophoretic mobility. Zeta (ζ) potential is identified with the diffuse potential at the shear plane ... -
Thermodynamics of ionic microgels
(2002) [Artigo de periódico]We present a theory of dilute aqueous suspensions of microgel particles. It is found that as the number of charged monomers in the polymer network composing mesoscopic gel increases, the particles undergo a swelling ...
