Standard thin-double-layer modeling of electro-osmotic flows about metal objects typically predicts an induced zeta-potential distribution whose characteristic magnitude varies linearly with the applied voltage. At moderately large zeta potential, comparable with several thermal voltages, surface co…

[Phys. Rev. E 86, 061506] Published Wed Dec 26, 2012

Monte Carlo computer simulation is employed to determine the local, wave-number-dependent, high-frequency elastic properties of a Lennard-Jones fluid that is confined between two walls. In particular, the elastic constants are calculated from coarse-grained stress correlation functions and then rela…

[Phys. Rev. E 86, 062501] Published Wed Dec 26, 2012

The translational dynamics of hydration water confined in calcium-silicate-hydrate (C-S-H) gel was studied by quasielastic neutron scattering spectroscopy in the temperature range from 280 to 230 K. The stretch exponent β, the self-diffusion constant $D$, the average translational relaxation time $\langle \tau \rangle$,…

[Phys. Rev. E 86, 061505] Published Thu Dec 20, 2012

The traditional modeling framework for determining streaming potential, when taking into consideration finite size effects, suffers from an oversight in that while the model incorporates the size effects in the ion distribution profiles, it neglects these very same effects in the flux contributions,…

[Phys. Rev. E 86, 061504] Published Mon Dec 17, 2012

We extend the quiescent and stressed versions of naïve mode coupling theory to treat the dynamical arrest, shear modulus, and absolute yielding of particle mixtures where one or more species is a nonrotating nonspherical object. The theory is applied in detail to dense isotropic “chemically matched”…

[Phys. Rev. E 86, 061503] Published Fri Dec 14, 2012

Over the past decade, computer simulations have had an increasing role in shedding light on difficult statistical physical phenomena, and in particular on the ubiquitous problem of the glass transition. Here in a wide variety of materials the viscosity of a supercooled liquid increases by many order…

[Phys. Rev. E 86, 061502] Published Mon Dec 10, 2012

Large density fluctuations were observed by illuminating a cylindrical cell filled with sulfur hexafluoride (SF${}_6$), very near its liquid-gas critical point ($|T-T_c|<300\mu \mathrm{K}$) and recorded using a microscope with 3 μm spatial resolution. Using a dynamic structure factor algorithm, we determined from th…

[Phys. Rev. E 86, 061501] Published Mon Dec 03, 2012

Two versions of the $M$-$p$-spin glass model have been studied with the Migdal-Kadanoff renormalization group approximation. The model with $p=3$ and $M=3$ has at mean-field level the ideal glass transition at the Kauzmann temperature and at lower temperatures still the Gardner transition to a state like th…

[Phys. Rev. E 86, 052501] Published Fri Nov 16, 2012

We investigate the dynamics of a binary mixture Lennard-Jones system of different system sizes with respect to the importance of the properties of the underlying potential energy landscape (PEL). We show that the dynamics of small systems can be very well described within the continuous time random …

[Phys. Rev. E 86, 051504] Published Thu Nov 15, 2012

Zhu et al. [L. Zhu, C. W. Brian, S. F. Swallen, P. T. Straus, M. D. Ediger, and L. Yu, Phys. Rev. Lett. 106, 256103 (2011)] measured the surface self-diffusion for an organic glass former, indomethacin, and found surface diffusion is more than 10${}^6$ times faster than bulk diffusion at temperatures aro…

[Phys. Rev. E 86, 051503] Published Wed Nov 07, 2012

Recently a Poisson-Helmholtz-Boltzmann (PHB) model [Bohinc et al., Phys. Rev. E 85, 031130 (2012)] was developed by accounting for solvent-mediated nonelectrostatic ion-ion interactions. Nonelectrostatic interactions are described by a Yukawa-like pair potential. In the present work, we modify the …

[Phys. Rev. E 86, 051502] Published Mon Nov 05, 2012

We present a technique for the determination of viscoelastic properties of a medium by tracking the motion of an embedded probe particle by using molecular dynamics simulations. The approach involves the analysis of the simulated particle motion by continuum theory; it is shown to work in both passi…

[Phys. Rev. E 86, 051501] Published Thu Nov 01, 2012

We study numerically the diffusion mechanism in silica liquid via molecular dynamics simulation. For this purpose we examine the evolution of structural units SiO${}_x$ ($x=4-6$) for different times and at temperatures from 3000 to 4500 K. Simulation shows that the diffusivity of the silicon particle is pe…

[Phys. Rev. E 86, 041508] Published Thu Oct 25, 2012

There is growing evidence that slow dynamics and dynamic heterogeneity possess structural signatures in glass-forming liquids. However, even in the weakly frustrated glass-forming liquids, whether or not the dynamic heterogeneity has a structural origin is a matter of debate. Via molecular dynamics …

[Phys. Rev. E 86, 041506] Published Fri Oct 19, 2012

The phenomenon of the glass transition is an unresolved problem in condensed matter physics. Its prominent feature, the super-Arrhenius temperature dependence of the transport coefficients, remains a challenge to be described over the full temperature range. For a series of molecular glass formers, …

[Phys. Rev. E 86, 041507] Published Fri Oct 19, 2012

Whether or not there is growing static order accompanying the dynamical heterogeneity and increasing relaxation times seen in glassy systems is a matter of dispute. An obstacle to resolving this issue is that the order is expected to be amorphous and so not amenable to simple order parameters. We us…

[Phys. Rev. E 86, 041505] Published Thu Oct 18, 2012

First-order transitions of system where both lattice site occupancy and lattice spacing fluctuate, such as cluster crystals, cannot be efficiently studied by traditional simulation methods, which necessarily fix one of these two degrees of freedom. The difficulty, however, can be surmounted by the g…

[Phys. Rev. E 86, 042501] Published Mon Oct 15, 2012

We investigate the dynamic heterogeneities of glassy particle systems in the theoretical schemes of bond breakage and four-point correlation functions. In the bond-breakage scheme, we introduce the structure factor $S_b(q,t)$ and the susceptibility ${\chi }_b\left(t\right)$ to detect the spatial correlations of configurat…

[Phys. Rev. E 86, 041504] Published Wed Oct 10, 2012

A simple and fast numerical method is developed capable of accurately determining the 3D rotational dynamics of a magnetic particle chain in an infinite fluid domain. The focus is to control the alternating breakup and reformation of the bead chain which we believe is essential to achieve effective …

[Phys. Rev. E 86, 041503] Published Tue Oct 09, 2012

Stable fluid filaments with diameters of several micrometers and slenderness ratios well above 1000 are unique objects formed by some liquid crystalline phases of bent-core mesogens. We present a technique to determine filament tensions from their deflection under defined loads. A strong temperature…

[Phys. Rev. E 86, 040501(R)] Published Mon Oct 08, 2012

We report that the pressure coefficient of the glass transition temperature, $d{T}_g$/$dp$, which is commonly used to determine the pressure sensitivity of the glass transition temperature $T_g$, can be predicted in the thermodynamic scaling regime. We show that the equation derived from the isochronal condit…

[Phys. Rev. E 86, 041502] Published Mon Oct 08, 2012

The aging-time dependence of the segmental relaxation time of poly(vinyl acetate) (PVAc) in the glassy state is investigated in the bulk polymer and its nanocomposites with silica (SiO${}_2$). These systems present identical segmental dynamics, when this is probed in the equilibrium supercooled liquid by…

[Phys. Rev. E 86, 041501] Published Mon Oct 01, 2012

Dielectric, calorimetric, and x-ray diffraction measurements were carried out on α-, β-, and γ-cyclodextrins, which are cyclic saccharides built by, respectively, six, seven, and eight glucose units connected via glycosidic linkage. Differential scanning calorimetry measurements indicated that each …

[Phys. Rev. E 86, 031506] Published Thu Sep 27, 2012

Critical behavior of soft repulsive particles after quench of temperature near the jamming transition is numerically investigated. It is found that the plateau of the mean-square displacement of tracer particles and the pressure satisfy critical scaling laws. The critical density for the jamming tra…

[Phys. Rev. E 86, 031505] Published Tue Sep 25, 2012

Effects of size and charge asymmetry between oppositely charged ions or particles on spatial inhomogeneities are studied for a large range of charge and size ratios. We perform a stability analysis of the primitive model of ionic systems with respect to periodic ordering using the collective variabl…

[Phys. Rev. E 86, 031504] Published Mon Sep 17, 2012

The formal structure of glass singularities in the mode-coupling theory (MCT) of supercooled liquids dynamics is closely related to that appearing in the analysis of heterogeneous bootstrap percolation on Bethe lattices, random graphs, and complex networks. Starting from this observation one can bui…

[Phys. Rev. E 86, 030502(R)] Published Fri Sep 14, 2012

We address the investigation of the solvation properties of the minimal orientational model for water originally proposed by [Bell and Lavis, J. Phys. A 3, 568 (1970)]. The model presents two liquid phases separated by a critical line. The difference between the two phases is the presence of structu…

[Phys. Rev. E 86, 031503] Published Wed Sep 12, 2012

We present a comprehensive theoretical study of finite-size effects in the relaxation dynamics of glass-forming liquids. Our analysis is motivated by recent theoretical progress regarding the understanding of relevant correlation length scales in liquids approaching the glass transition. We obtain p…

[Phys. Rev. E 86, 031502] Published Mon Sep 10, 2012

The anomalous mesoscopic transport in supercooled liquids was investigated using three-dimensional molecular dynamics simulation. We show that the dynamic correlation length, $\xi$, can be identified as a crossover length between the microscopic and macroscopic transports. We also find that in highly su…

[Phys. Rev. E 86, 030501(R)] Published Wed Sep 05, 2012

The crucial problem for better understanding the nature of glass transition and related relaxation phenomena is to find proper interrelations between the molecular dynamics and thermodynamics of viscous systems. To make progress towards this goal the recently observed density scaling of viscous liqu…

[Phys. Rev. E 86, 031501] Published Tue Sep 04, 2012

Using a combination of light scattering techniques and broadband dielectric spectroscopy, we have measured the temperature dependence of structural relaxation time and self diffusion in three imidazolium-based room temperature ionic liquids: [bmim][NTf${}_2$], [bmim][PF${}_6$], and [bmim][TFA]. A detailed ana…

[Phys. Rev. E 86, 021508] Published Fri Aug 31, 2012

High resolution quasielastic neutron scattering measurements have been used to study the effects of applied electric field on the dynamics of water molecules confined in the pores of folded silica sheet material FSM-12 with an average pore diameter (apd) of 16 Å. In the absence of field, there is a …

[Phys. Rev. E 86, 021506] Published Fri Aug 24, 2012

Shear can impart a high degree of orientational order to supported block copolymer thin films containing one or more layers of cylindrical microdomains, leading to a striped pattern with a period of tens of nanometers extending over macroscopic (centimeter-squared) areas. Though the as-deposited fil…

[Phys. Rev. E 86, 021507] Published Fri Aug 24, 2012

Maximally random jammed states of hard spheres are prototypical glasses. We study the small wavenumber $k$ behavior of the structure factor $S\left(k\right)$ of overcompressed million-sphere packings as a function of density up to the jammed state. We find both a precursor to the glassy jammed state evident long b…

[Phys. Rev. E 86, 021505] Published Thu Aug 23, 2012

For highly charged dielectric surfaces, the asymptotic structure underlying electrokinetic phenomena in the thin-double-layer limit reshuffles. The large counterion concentration near the surface, associated with the Boltzmann distribution in the diffuse layer, supports appreciable tangential fluxes…

[Phys. Rev. E 86, 021503] Published Wed Aug 15, 2012

We study closed liquid membranes that segregate into three phases due to differences in the chemical and physical properties of its components. The shape and in-plane membrane arrangement of the phases are coupled through phase-specific bending energies and line tensions. We use simulated annealing …

[Phys. Rev. E 86, 021504] Published Wed Aug 15, 2012

We present a detailed derivation of a microscopic theory for the glass transition of a liquid enclosed between two parallel walls relying on a mode-coupling approximation. This geometry lacks translational invariance perpendicular to the walls, which implies that the density profile and the density-…

[Phys. Rev. E 86, 021502] Published Fri Aug 10, 2012

Glass transition in thin (1–200 nm thick) spin-cast polystyrene films on silicon surfaces is probed by ellipsometry in a controlled vacuum environment. A temperature-modulated modification of the method is used alongside a traditional linear temperature scan. A clear glass transition is detected in …

[Phys. Rev. E 86, 021501] Published Tue Aug 07, 2012

Molecular dynamics simulations were carried out to investigate the reorientational motion of a rigid (fixed bond length), asymmetric diatomic molecule in the liquid and glassy states. In the latter the molecule reorients via large-angle jumps, which we identify with the Johari-Goldstein (JG) dynamic…

[Phys. Rev. E 86, 020501(R)] Published Wed Aug 01, 2012

We study Seebeck effect in liquid electrolytes, starting from its simple neutral analog—thermodiffusion (so-called Ludwig-Soret or Soret effect). It is observed that when two or more subsystems of mobile particles are subjected to the temperature gradient, various types of them respond to it differe…

[Phys. Rev. E 86, 011505] Published Tue Jul 24, 2012

Molecular dynamic simulations of a strongly inhomogeneous system reveals that a single-component soft-sphere fluid can behave as a fragile glass former due to confinement. The self-intermediate scattering function, $F_s(k,t)$, of a Lennard-Jones fluid confined in slit-shaped pores, which can accomodate…

[Phys. Rev. E 86, 011504] Published Mon Jul 23, 2012

A wide range of glassy and disordered materials exhibit complex, nonexponential, structural relaxation (aging). We propose a simple nonlinear rate equation $\dot{\delta }=a[1-\exp \left(b\delta \right)]$, where $\delta$ is the normalized deviation of a macroscopic variable from its equilibrium value, to describe glassy relaxation. Analys…

[Phys. Rev. E 86, 010501(R)] Published Fri Jul 20, 2012

This article presents the study of the generic behavior of viscosity of liquids based on some simple theoretical models, the soft-spheres and Lennard-Jones systems. The use of these simple models allows us to investigate in detail the viscosity behavior in a wide range of temperatures and pressures …

[Phys. Rev. E 86, 011503] Published Fri Jul 13, 2012

We present a shear-transformation-zone (STZ) theoretical analysis of molecular-dynamics simulations of a rapidly sheared metallic glass. These simulations are especially revealing because, although they are limited to high strain rates, they span temperatures ranging from well below to well above th…

[Phys. Rev. E 86, 011502] Published Thu Jul 12, 2012

Converting time dependent creep compliance to frequency dependent complex shear modulus is an important step in analyzing the results of particle tracking microrheology. Fitting a function to the whole time range and transforming it to calculate the shear modulus is one way of solving this problem. …

[Phys. Rev. E 86, 011501] Published Thu Jul 05, 2012

When a liquid melt is cooled, a glass or phase transition can be obtained depending on the cooling rate. Yet, this behavior has not been clearly captured in energy-landscape models. Here, a model is provided in which two key ingredients are considered in the landscape, metastable states and their mu…

[Phys. Rev. E 85, 061505] Published Thu Jun 28, 2012

We developed a statistical model which describes the thermal and volumetric properties of water-like molecules. A molecule is presented as a three-dimensional sphere with four hydrogen-bonding arms. Each water molecule interacts with its neighboring waters through a van der Waals interaction and an …

[Phys. Rev. E 85, 061503] Published Mon Jun 25, 2012

The microscopic nonlinear Langevin equation (NLE) theory of correlated two-particle dynamics in dense fluids of spherical particles is extended to construct a predictive model of multiple correlated hopping and recaging events of a pair of tagged particles as a function of their initial separation. …

[Phys. Rev. E 85, 061504] Published Mon Jun 25, 2012

By characterizing the dynamics of idealized lattice models with a tunable kinetic constraint, we explore the different ways in which dynamical facilitation manifests itself within the local dynamics of glassy materials. Dynamical facilitation is characterized both by a mobility transfer function, th…

[Phys. Rev. E 85, 061502] Published Wed Jun 20, 2012

Generic glass formers exhibit at least two characteristic changes in their relaxation behavior, first to an Arrhenius-type relaxation at some characteristic temperature and then at a lower characteristic temperature to a super-Arrhenius (fragile) behavior. We address these transitions by studying th…

[Phys. Rev. E 85, 061501] Published Thu Jun 07, 2012

We have adopted an ensemble Monte Carlo simulation method to systematically verify two physical driving mechanisms responsible for overcharging which refers to the adsorption of an effective charge onto a like-charged planar surface around the point of zero charge within the primitive model of mixed…

[Phys. Rev. E 85, 062501] Published Tue Jun 05, 2012

The temperature and density dependence of the structure and polarization properties of bulk water were systematically investigated using the ab initio MCYna potential [Li et al., J. Chem. Phys. 127, 154509 (2007)], which includes nonadditive contributions to intermolecular interactions. Molecular d…

[Phys. Rev. E 85, 051509] Published Wed May 30, 2012

In this paper we delineate the consequences of field-dependent solvent polarization in the electric double layer (EDL) electrostatic potential distribution, and the effective EDL thickness in narrow nanofluidic confinements with thick (or overlapping) EDLs. The EDL, formed at the interface between a…

[Phys. Rev. E 85, 051508] Published Tue May 29, 2012

The shear-transformation-zone (STZ) theory has been remarkably successful in accounting for broadly peaked, frequency-dependent, viscoelastic responses of amorphous systems near their glass temperatures $T_g$. This success is based on the theory's first-principles prediction of a wide range of internal…

[Phys. Rev. E 85, 051507] Published Thu May 24, 2012

The effects of water confined in regions between self-assembling entities is relevant to numerous contexts such as macromolecular association, protein folding, protein-ligand association, and nanomaterials self-assembly. Thus assessing the impact of confined water, and the ability of current modelin…

[Phys. Rev. E 85, 051506] Published Wed May 23, 2012

We use an elastic model to explore faceting of solid-wall vesicles with elastic heterogeneities. We show that faceting occurs in regions where the vesicle wall is softer, such as areas of reduced wall thicknesses or concentrated in crystalline defects. The elastic heterogeneities are modeled as a se…

[Phys. Rev. E 85, 050501(R)] Published Tue May 22, 2012

The response to an electric field of electrolytic solutions, gels, liquid crystals, and other soft materials is described by the drift-diffusion and Poisson equations. Existing models, used for the interpretation of experimental data, usually consider the system as one dimensional (1D), which is val…

[Phys. Rev. E 85, 051505] Published Mon May 21, 2012

In this paper we study the critical behavior of the fully connected $p$-color Potts spin glass at the dynamical transition. In the framework of mode coupling theory (MCT), the time autocorrelation function displays a two-step relaxation, with two exponents governing the approach to the plateau and the…

[Phys. Rev. E 85, 051504] Published Tue May 15, 2012

Although the presence of hydrogen bonds determines most properties of associated materials, their role in relaxation dynamics of liquids remains unclear. Very recently Nakanishi and Nozaki [M. Nakanishi and R. Nozaki, Phys. Rev. E 84, 011503 (2011)] proposed a simplified model for the description of…

[Phys. Rev. E 85, 052501] Published Thu May 10, 2012

Using discrete molecular dynamics simulations we study the relation between the thermodynamic and diffusive behaviors of a primitive model of aqueous solutions of hydrophobic solutes consisting of hard spheres in the Jagla particles solvent, close to the liquid-liquid critical point of the solvent. …

[Phys. Rev. E 85, 051503] Published Wed May 09, 2012

The theory of nonlinear response for Markov processes obeying a master equation is formulated in terms of time-dependent perturbation theory for the Green's functions and general expressions for the response functions up to third order in the external field are given. The nonlinear response is calcu…

[Phys. Rev. E 85, 051502] Published Tue May 08, 2012

Using the time dependence of density fluctuations in a supercooled liquid obtained from the solutions of the equations of nonlinear fluctuating hydrodynamics (NFH), the evolution of the system in the free energy landscape is studied. A crossover from a continuous fluid type dynamics to that of hoppi…

[Phys. Rev. E 85, 051501] Published Tue May 01, 2012

We propose a kinetic mechanism of electrochemical interactions. We assume fast formation and recombination of electron donors ${\mathcal{D}}^{-}$ and acceptors ${\mathcal{A}}^{+}$ on electrode surfaces. These mediators are continuously formed in the electrode matter by thermal fluctuations. The mediators ${\mathcal{D}}^{-}$ and ${\mathcal{A}}^{+}$, chemically equiva…

[Phys. Rev. E 85, 041505] Published Wed Apr 25, 2012

We analyze the appropriate form for the generalized Stokes-Einstein relation (GSER) for viscoelastic solids and fluids when bead inertia and medium inertia are taken into account, which we call the inertial GSER. It was previously shown for Maxwell fluids that the Basset (or Boussinesq) force arisin…

[Phys. Rev. E 85, 041504] Published Fri Apr 20, 2012

In the energy landscape picture, the dynamics of glasses and crystals is usually decomposed into two separate contributions: interbasin and intrabasin dynamics. The intrabasin dynamics depends partially on the quadratic displacement distribution on a given metabasin. Here we show that such a distrib…

[Phys. Rev. E 85, 041503] Published Wed Apr 18, 2012

By numerical simulations, it is illustrated that a magnetic dipole with a flexible tail behaves as a swimmer in AC magnetic fields. The behavior of the swimmer on long time scales is analyzed and it is shown that due to the flexibility of the tail two kinds of torques arise, the first is responsible…

[Phys. Rev. E 85, 041502] Published Tue Apr 17, 2012

Based on previous works on polymers by Bauer et al. [Phys. Rev. E 61, 1755 (2000)], this paper describes a capacitative method for measuring the dynamical expansion coefficient of a viscous liquid. Data are presented for the glass-forming liquid tetramethyl tetraphenyl trisiloxane (DC704) in the ult…

[Phys. Rev. E 85, 041501] Published Mon Apr 09, 2012

When a fluid is confined within a spatially periodic external field, the liquid-vapor transition is replaced by a different transition called laser-induced condensation (LIC) [Götze et al., Mol. Phys. 101, 1651 (2003)]. In $d=3$ dimensions, the periodic field induces an additional phase, characterize…

[Phys. Rev. E 85, 031505] Published Tue Mar 27, 2012

We study the temperature dependence of the structure and orientation of the first hydration layers of the protein lysozyme and compare it with the situation for a model homogeneous hydrophobic surface, a graphene sheet. We show that in both cases these layers are significantly better structured than…

[Phys. Rev. E 85, 031503] Published Fri Mar 23, 2012

We investigate cage breaking in dense hard-disk systems using a model of three Brownian disks confined within a circular corral. This system has a six-dimensional configuration space, but can be equivalently thought to explore a symmetric one-dimensional free-energy landscape containing two energy m…

[Phys. Rev. E 85, 031504] Published Fri Mar 23, 2012

We employ the techniques of microparticle image velocimetry and full-field birefringence microscopy combined with mechanical measurements of the pressure drop to perform a detailed characterization of the extensional rheology and elastic flow instabilities observed for a range of wormlike micellar s…

[Phys. Rev. E 85, 031502] Published Wed Mar 14, 2012

Nanoconfined water and surface-structured water impacts a broad range of fields. For water confined between hydrophilic surfaces, measurements and simulations have shown conflicting results ranging from “liquidlike” to “solidlike” behavior, from bulklike water viscosity to viscosity orders of magnit…

[Phys. Rev. E 85, 031501] Published Thu Mar 08, 2012

The dynamic modulus $G^{*}$ of a viscoelastic medium is often measured by following the trajectory of a small bead subject to Brownian motion in a method called “passive microbead rheology.” This equivalence between the positional autocorrelation function of the tracer bead and $G^{*}$ is assumed via the gene…

[Phys. Rev. E 85, 021504] Published Fri Feb 24, 2012

Confinement can have a dramatic effect on the behavior of all sorts of particulate systems, and it therefore is an important phenomenon in many different areas of physics and technology. Here, we investigate the role played by the softness of the confining potential. Using grand canonical Monte Carl…

[Phys. Rev. E 85, 021502] Published Tue Feb 21, 2012

We perform molecular dynamics simulations to characterize the occurrence of inhomogeneous shear flows in soft jammed materials. We use rough walls to impose a simple shear flow and study the athermal motion of jammed assemblies of soft particles in two spatial dimensions, both for purely repulsive i…

[Phys. Rev. E 85, 021503] Published Tue Feb 21, 2012

We develop a framework for understanding the difference between strong and fragile behavior in the dynamics of glass-forming liquids from the properties of the potential energy landscape. Our approach is based on a master equation description of the activated jump dynamics among the local minima of …

[Phys. Rev. E 85, 021501] Published Tue Feb 14, 2012

Using molecular dynamics simulations, we calculate fluctuations and responses for steadily sheared hard spheres over a wide range of packing fractions $\phi$ and shear strain rates $\dot{\gamma }$, using two different methods to dissipate energy. To a good approximation, shear stress and density fluctuations are rela…

[Phys. Rev. E 85, 011503] Published Mon Jan 30, 2012

We analyze bulk diffusion and transport through hydrophobic nanochannels of nanoparticles (NPs) with different hydrophobic-hydrophilic patterns achieved by coating a fraction of the NP sites with positive or negative charges via explicit solvent molecular dynamics simulations. Ten different charge p…

[Phys. Rev. E 85, 011504] Published Mon Jan 30, 2012

In a recent study [S. Das and S. Hardt, Phys. Rev. E 84, 022502 (2011).], we provided analytical results for the electric-double-layer (EDL) electrostatic potential distribution in a system of immiscible electrolyte layers confined between plates with gap dimensions comparable to the EDL thickness. …

[Phys. Rev. E 85, 012502] Published Tue Jan 17, 2012

Off-equilibrium dynamics of a three-dimensional lattice model with nearest- and next-nearest-neighbors exclusions is studied. At equilibrium, the model undergoes a first-order fluid-solid transition. Nonequilibrium filling, through random sequential adsorption with diffusion, creates amorphous struc…

[Phys. Rev. E 85, 011502] Published Mon Jan 09, 2012

A phase-separation front will leave in its wake a phase-separated morphology that differs markedly from homogeneous phase-separation morphologies. For a purely diffusive system such a front, moving with constant velocity, will generate very regular, nonequilibrium structures. We present here a numer…

[Phys. Rev. E 85, 011501] Published Thu Jan 05, 2012

We focus on a system consisting of an elastic part and a damageable part in series, to study the relaxation creep rupture of a heterogeneous system subjected to a uniaxial constant strain applied instantaneously. The viscoelastic behavior of the damageable part is modeled by a fiber bundle model con…

[Phys. Rev. E 85, 012501] Published Tue Jan 03, 2012

The effect of the boundary friction coefficient on the rheological properties of the electrorheological (ER) fluids in quasistatic and dynamic states is investigated by computer simulation. The relation between the shear stress and the boundary friction coefficient in quasistatic and dynamic states …

[Phys. Rev. E 84, 061505] Published Tue Dec 20, 2011

Salt transport in bulk electrolytes is limited by diffusion and advection, but in microstructures with charged surfaces (e.g., microfluidic devices, porous media, soils, or biological tissues) surface conduction and electro-osmotic flow also contribute to ionic fluxes. For small applied voltages, th…

[Phys. Rev. E 84, 061504] Published Mon Dec 19, 2011

Dynamic heterogeneity is now considered to be an intrinsic kinetic feature of a supercooled liquid. Here, we access the nonlocal complex modulus of a glass-forming liquid using molecular dynamics simulations. We find that the shear-stress relaxation exhibits a marked wave number dependence in a supe…

[Phys. Rev. E 84, 061503] Published Wed Dec 14, 2011

We reexamine the convolution approximation commonly used in the mode-coupling theory (MCT) of nonergodic states of classical fluids. This approximation concerns the static correlation functions used as input in the MCT treatment of the dynamics. Besides the hard-sphere model, we consider interaction…

[Phys. Rev. E 84, 061502] Published Mon Dec 05, 2011

We show that a fluid under strong spatially periodic confinement displays a glass transition within mode-coupling theory at a much lower density than the corresponding bulk system. We use fluctuating hydrodynamics, with confinement imposed through a periodic potential whose wavelength plays an impor…

[Phys. Rev. E 84, 061501] Published Fri Dec 02, 2011

Gas-liquid phase coexistence curves of the polarizable Stockmayer fluid in external electric fields are computed using molecular dynamics computer simulation. We study in particular the critical-point shift dependence on polarizability and external electric field distinguishing the cases of fixed ch…

[Phys. Rev. E 84, 051508] Published Mon Nov 28, 2011

Nucleosides are chemical compounds that have an extremely important biological role; they can be found in all types of living organisms. They are crucial components from which DNA and RNA acids are built. In addition, nucleosides are key regulators of many physiological processes. In this paper, the…

[Phys. Rev. E 84, 051507] Published Wed Nov 23, 2011

The viscosity and diffusivities of silicate melts under high-pressure, high-temperature conditions are difficult to obtain experimentally. Estimation and extrapolation of transport coefficients are further complicated by their extreme sensitivity to melt composition. Our molecular-dynamics simulatio…

[Phys. Rev. E 84, 051506] Published Mon Nov 21, 2011

The predictions of the mode-coupling theory (MCT) for the dynamical arrest scenarios in a partly pinned (PP) fluid system are reported. The corresponding dynamical phase diagram is found to be very similar to that of a related quenched-annealed (QA) system. The only significant qualitative differenc…

[Phys. Rev. E 84, 050501(R)] Published Thu Nov 17, 2011

We propose a simple nonlocal energy functional that is suitable for the continuum field characterization of nonperiodic and localized textures. The phenomenological functional is based on the pairwise direction-dependent interaction of field gradients that are separated by a fixed distance. In an ap…

[Phys. Rev. E 84, 051505] Published Wed Nov 16, 2011

We employ a continuum theory of solvent-free ionic liquids accounting for both short-range electrostatic correlations and steric effects (finite ion size) [Bazant et al., Phys. Rev. Lett. 106, 046102 (2011)] to study the response of a model microelectrochemical cell to a step voltage. The model pro…

[Phys. Rev. E 84, 051504] Published Tue Nov 15, 2011

Using molecular dynamics simulations we study, in two dimensions, the temperature-density phase diagram of a simple model with two internal states labeled 1 and $-1$. The particles interact with a modified Lennard-Jones potential, which depends on relative positions of the particles as well as on thei…

[Phys. Rev. E 84, 051503] Published Mon Nov 14, 2011

Rheological properties of soft materials are often investigated in oscillatory shear and characterized by the storage and loss modulus, $G^{\prime }$ and $G^{\prime \prime }$, respectively. Unfortunately, the relaxation dynamics of most soft materials is too slow to be directly probed by commercial rheometers. Recently, it was…

[Phys. Rev. E 84, 051502] Published Mon Nov 07, 2011

In this Brief Report we show that key parameters, the fragility $m_p$ and activation volume ΔV, which characterize the sensitivity of molecular dynamics near the glass transition to temperature and pressure changes, respectively, reflect molecular properties in a nonequivalent way. Our comparative stud…

[Phys. Rev. E 84, 052501] Published Thu Nov 03, 2011

Based on the trajectories of the separation between water molecule pairs from MD simulations, we investigate the bond breakage dynamics in bulk water. From the spectrum of mean first-passage times, the Fokker-Planck equation allows us to derive the diffusivity profile along the separation coordinate…

[Phys. Rev. E 84, 051501] Published Wed Nov 02, 2011

Recently an alternative approach to the determination of dynamic correlation lengths ξ for supercooled liquids, based on the properties of the slow (picosecond) vibrational dynamics, was carried out [Hong, Novikov, and Sokolov, Phys. Rev. E 83, 061508 (2011)]. Although these vibrational measurements…

[Phys. Rev. E 84, 042501] Published Mon Oct 31, 2011

Quasielastic neutron scattering (QENS) was used to investigate the diffusion dynamics of hydration water on the surface of rutile (TiO${}_2$) nanopowder. The dynamics measurements utilizing two inelastic instruments, a backscattering spectrometer and a disk chopper spectrometer, probed the fast, intermed…

[Phys. Rev. E 84, 031505] Published Fri Sep 30, 2011

We explore the possibility of describing experimental susceptibility spectra of the glass former propylene carbonate with a two-component schematic model of mode-coupling theory (MCT) from above the melting point down to temperatures far below the critical temperature of MCT. By introducing a phenom…

[Phys. Rev. E 84, 031506] Published Fri Sep 30, 2011