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Abstract: Interphases appear in heterogeneous media in a variety of forms. Often the treatment of a thin interphase as a separate phase in a multiphase solid is not convenient in analytical or numerical solutions of those systems. Thus, approximate models of a thin interphase that make possible to obtain a solution for the fields in the media adjacent to it, without the need of determining the fields within the interphase itself, become a necessity in many cases. The question then arises whether a global property which was present in the original heterogeneous medium will continue to prevail after an approximate representation of the thin interphase has been introduced in the system. A global property, known to have important consequences on the behavior of the heterogeneous solid, is the “reciprocity” relation between a pair of two different solutions, as stated by the reciprocal theorem. Since the formulation of an approximate model for the thin interphase involves several assumptions, the fulfillment of the reciprocal theorem in the original system does not necessarily imply its fulfillment in the transformed system in which an approximate model of the thin interphase has been intoduced. The preservation of the reciprocity relation by the approximate model, if proved, would be considered to be an important consistency quality of the model. In this paper we consider steady thermal conduction phenomena, and generalize the two approximate models of a thin interphase by Bövik (1994), Benveniste (2006), Benveniste and Berdichevsky (2010) to the case of thin interphases with a variable conductivity. The fulfillment of the reciprocity property in the presence of those models, which was not discussed in the above papers, is investigated here in the context of their presently developed generalized version, and it is proved that both models fulfill the reciprocal theorem. [Copyright &y& Elsevier]

We study the physics of a three-component Fermi gas in an optical lattice, in the presence of a three-body constraint arising due to strong three-body loss. Using analytical and numerical techniques, we show that an atomic color superfluid phase is formed in this system and undergoes phase separation between unpaired fermions and superfluid pairs. This phase separation survives well above the critical temperature, giving a clear experimental signature of the three-body constraint. [ABSTRACT FROM AUTHOR]

We consider a two-component Bose-Einstein condensate, which contains atoms with magnetic dipole moments aligned along the z direction (labeled as component 1) and nonmagnetic atoms (labeled as component 2). The problem is studied by means of exact numerical simulations. The effects of dipole-dipole interaction on phase separations are investigated. It is shown that, in the quasi-one-dimensional regime, the atoms in component 2 are squeezed out when the dimensionless dipolar strength parameter is small, whereas the atoms in component 1 are pushed out instead when the parameter is large. This is in contrast to the phenomena in the quasi-two-dimensional regime. These two components are each kicked out by the other in the quasi-one-dimensional regime and this phenomenon is discussed as well. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study the effects of traffic light period in two-dimensional Biham–Middleton–Levine (BML) traffic flow model. It is found that a phase separation phenomenon, in which the system separates into coexistence of free flow and jam, could be observed in intermediate vehicle density range when traffic light period . We have explained the reason of occurrence of phase separation and investigated its behavior in different traffic light period. [Copyright &y& Elsevier]

In this article we consider mixtures of non-adsorbing polymers and rod-like colloids in the isotropic phase, which upon the addition of polymers show an effective attraction via depletion forces. Above a certain concentration, the depletant causes phase separation of the mixture. We performed Monte Carlo simulations to estimate the phase boundaries of isotropic–isotropic coexistence. To determine the phase boundaries we simulated in the grand canonical ensemble using successive umbrella sampling [J. Chem. Phys. 120 (2004) 10925]. The location of the critical point was estimated by a finite size scaling analysis. In order to equilibrate the system efficiently, we used a cluster move in which rods and spheres were exchanged. [Copyright &y& Elsevier]

The phase separation kinetics of binary fluids in constrained geometry is a challenge for computer simulation, since nontrivial structure formation occurs extending from the atomic scale up to mesoscopic scales, and a very large range of time needs to be considered. One line of attack to this problem is to try nevertheless standard Molecular Dynamics (MD), another approach is to coarse-grain the model to apply a time-dependent nonlinear Ginzburg–Landau equation that is numerically integrated. For a symmetric binary mixture confined between two parallel walls that prefer one species, both approaches are applied and compared to each other. There occurs a nontrivial interplay between the formation of a stratified structure due to enrichment layers of the component preferred by the walls, and lateral phase separation. While the former process already occurs during the initial stages, the latter dominates during intermediate and late stages. The extent to which the two methods are equivalent when one suitably translates the time scales is critically discussed. [Copyright &y& Elsevier]

The metal organic vapor phase epitaxy (MOVPE) growth of indium gallium nitride (InGaN) has been discussed in detail towards the fabrication of solar cell. The InGaN film with In contents up to 0.4 are successfully grown by controlling the fundamental growth parameters such as the precursor gas flow rates, temperature etc. The formation of metallic In originates from the higher value (0.74) of trimethylindium/(trimethylindium + triethylgallium) (TMI/(TMI + TEG)) molar ratio with low (4100) V/III weight molar ratio while the lower value (0.2) of TMI/(TMI + TEG) causes the phase separation. It is also necessary to control the growth rate and epitaxial film thickness to suppress the phase separation in the material. The crystalline quality of grown films is studied and it is found to be markedly deteriorated with increasing In content. The lattice parameters as well as the thermal expansion coefficient mismatch between GaN template and InGaN epi-layer are primarily considered as the reasons to deteriorate the film quality for higher In content. By using In0.16Ga0.84N films, an n+–p homo-junction structure is fabricated on 0.65 μm GaN template. For such a device, the response to the light illumination (AM 1.5) is observed with an open circuit voltage of 1.4 V and the short circuit current density of 0.25 mA/cm2. To improve the performance as well as increase solar photon capturing, the device is further fabricated on thick GaN template with higher In content. The In0.25Ga0.75N n+–p junction solar cell is found better performance with an open circuit voltage of 1.5 V and the short circuit current density of 0.5 mA/cm2. This is the InGaN p–n homo-junction solar cell with the highest In content ever reported by MOVPE. [ABSTRACT FROM AUTHOR]

The homogeneous liquid was separated into two phases, (Fe, Co)-rich L1 and Cu-rich L2, once the melt was undercooled below a liquid-phase separation temperature T sep. If the duration from T sep to T s1 (solidification temperature of L1 phase), termed the liquid-phase separation interval Δt, exceeded a critical value, an eggtype structure was observed. By utilizing differential thermal analyses (DTA), the solidification process of the undercooled Fe-Co-Cu alloys was studied. Additionally, an immiscible boundary was obtained, which was a convex parabola with a symmetrical axis of x Cu=0.52. Depending on the relative amounts of L1 and L2, the minor phase was nucleated firstly to form liquid droplets and separated from the original liquids at the beginning of liquid-phase separation. [Copyright &y& Elsevier]

The article features the SPRn series of sound velocity sensors used for concentration measurement and phase separation from Anton Paar.

Abstract: This paper studies slow-to-start effect in two-dimensional Biham–Middleton–Levine (BML) traffic flow model with traffic light periods . In most cases, the model exhibits free flow, jam, and phase separation phenomenon. Nevertheless, when the slow-to-start parameter , and traffic light parameter or 5, it is found that phase separation phenomenon does not occur. We have explained this via the evolution process from a designed regular initial configuration. Moreover, it is also found that the free flow self-organizes into grid-like structure when τ is large and the slow-to-start parameter . [Copyright &y& Elsevier]

We investigate a system of fermions on a two-dimensional optical square lattice in the strongly repulsive coupling regime. In this case, the interactions can be controlled by laser intensity as well as by Feshbach resonance. We compare the energetics of states with resonating valence bond rf-wave superfluidity, antiferromagnetic long-range order, and a homogeneous state with coexistence of superfluidity and antiferromagnetism. Using a variational formalism, we show that the energy density of a hole ehole(x) has a minimum at doping x = xc that signals phase separation between the antiferromagnetic and rf-wave paired superfluid phases. The energy of the phase-separated ground state is, however, found to be very close to that of a homogeneous state with coexisting antiferromagnetic and superfluid orders. We explore the dependence of the energy on the interaction strength and on the three-site hopping terms and compare with the nearest-neighbor hopping t-J model. [ABSTRACT FROM AUTHOR]

The article provides suggestions on proper maintenance and use of boat engine fluids. It states that serious problems can occur if the water/ethanol solution becomes greater than a half percent. Draining the tank is said to be the only thing to do when phase separation occurs. For boats with closed cooling system the proper mix of water and antifreeze is suggested. Also included are facts and maintenance tips on transmission fluid, potable water, and power steering fluid.

The article reports that a 6-month study in 2007 was conducted by he Trimeric Corp. and Noble Energy Inc. for the purpose of evaluating multiple types of three phase separators, enclosed flares, and vaporrecovery units. The study also looked into a new type of separator to reduce volatile organic compound (VOC) emissions and found advantages for using slug catchers upstream of separators and surge bottles downstream of separators.

The article presents updates on experiments on microgravity as of December 2013. The Supercritical Water Mixture experiment began a testing program inside the French space agency CNES' mini-laboratory called DECLIC. The Constrained Vapor Bubble experiment achieved the first-ever controlled visualizations of explosive boiling in a confined system in microgravity. The Binary Colloidal Alloy Test showed the first observations of phase separation beyond where a model critical fluid was to separate.

Highlights: [•] Multiphase LBM model is employed. [•] Coupling of reaction and hydrodynamics using LBM. [•] Flow around a droplet is simulated. [•] Mean field deterministic and kinetic Monte Carlo are used for reaction kinetics. [Copyright &y& Elsevier]

We investigate the ground state of spin-orbit-coupled Bose-Einstein condensates confined in concentrically coupled annular traps within the full parameter space accounts for all the nonlinear two-body collisions and the spin-orbit coupling. We find that depending on the ratio between interaction parameters and the strength of spin-orbit coupling, this coupled system presents various ground-state phases. Moreover, phase transition between radial phase separation and azimuthal phase separation can be induced by varying the strength of spin-orbit coupling when the system is first in radial phase separation, while phase transition between phase coexistence and azimuthal phase separation can also be realized through spin-orbit coupling when the system is first in phase coexistence. Finally, the spin texture is studied and the results show that the meron-antimeron pair spontaneously appears as the ground state of this coupled system. We also give an experimental protocol to observe these phenomena in future experiments. [ABSTRACT FROM AUTHOR]

It is of central importance to probe the local spectral function A(k, ω) of a strongly interacting Fermi gas in a trap. Momentum-resolved rf spectroscopy has been demonstrated to be able to probe the trap-averaged A(k, ω). However, the usefulness of this technique was limited by the trap inhomogeneity. Independent of a specific theory, here we propose that by studying the momentum-resolved rf spectra of the minority fermions of a phase-separated, population-imbalanced Fermi gas at low temperature, one can effectively extract A(k, ω) of a homogeneous superfluid Fermi gas (at the trap center). In support, we present calculated spectral functions and spectral intensity maps for various cases from BCS through Bose-Einstein condensation regimes using different theories. [ABSTRACT FROM AUTHOR]

This paper proposes a benchmark problem for the two- and three-dimensional Cahn–Hilliard (CH) equations, which describe the process of phase separation. The CH equation is highly nonlinear and an analytical solution does not exist except trivial solutions. Therefore, we have to approximate the CH equation numerically. To test the accuracy of a numerical scheme, we have to resort to convergence tests, which consist of consecutive relative errors or a very fine solution from the numerical scheme. For a fair convergence test, we provide benchmark problems which are of the shrinking annulus and spherical shell type. We show numerical results by using the explicit Euler’s scheme with a very fine time step size and also present a comparison test with Eyre’s convex splitting schemes. [ABSTRACT FROM AUTHOR]

We study a mechanism to create a vorton or three-dimensional skyrmion in phase-separated two-component BECs with the order parameters &psgr;1 and &psgr;2 of the two condensates. We consider a pair of a domain wall (brane) and an antidomain wall (antibrane) stretched by vortices (strings), where the &psgr;2 component with a vortex winding is sandwiched by two domains of the &psgr;1 component. The vortons appear when the domain wall pair annihilates. Experimentally, this can be realized by preparing the phase separation in the order &psgr;1, &psgr;2 and &psgr;1 components, where the nodal plane of a dark soliton in &psgr;&bar;1 component is filled with the &psgr;&bar;2 component with vorticity. By selectively removing the filling &psgr;&bar;2 component gradually with a resonant laser beam, the collision of the brane and antibrane can be made, creating vortons. [ABSTRACT FROM AUTHOR]

We present a density-functional theory for the one-dimensional harmonically trapped Bose-Fermi mixture with repulsive contact interactions. The ground-state density distribution of each component is obtained by solving the Kohn-Sham equations numerically based on the local density approximation and the exact solution for the homogeneous system given by Bethe ansatz method. It is shown that for sufficiently strong interaction, a considerable amount of fermions are repelled out of the central region of the trap, exhibiting partial phase separation of Bose and Fermi components. Oscillations emerge in the Bose density curves, reflecting the strong correlation with fermions. For infinitely strong interaction, the ground-state energy of the mixture and the total density are consistent with the scenario that all atoms in the mixture are fully fermionized. [ABSTRACT FROM AUTHOR]

A gas of ultracold 6Li atoms (effective spin 1/2) confined to an elongated trap with one-dimensional properties is a candidate to display three different phases: (i) fermions bound in Cooper-pair-1 ike states, (ii) unbound spin-polarized particles, and (iii) a mixed phase in which Cooper bound states and unpaired particles coexist. It is of great interest to extend these studies to fermionic atoms with higher spin, e.g., for neutral 40K, 43Ca, 87Sr, or 173Yb atoms. Within the grand-canonical ensemble, we investigated the p versus H phase diagram (μ is the chemical potential and H the external magnetic field) for S = 3/2, …, 9/2 for the ground state using the exact Bethe ansatz solution of the one-dimensional Fermi gas with an attractive δ-function interaction potential. There are N = 2S + 1 fundamental states: the particles can be either unpaired or clustered in bound states of 2, 3,... 2S, and 2S + 1 fermions. The rich phase diagram consists of these N states and various mixed phases in which combinations of the fundamental states coexist. Bound states of N fermions are not favorable in high magnetic fields, but always present if the field is low. For S = 3/2, possible scenarios for phase separation are explored within the local density approximation. For S = 3/2, the phase diagram for the superposition of a Zeeman and a quadrupolar splitting is also discussed. [ABSTRACT FROM AUTHOR]

We examine the density profiles of the quantum degenerate Bose-Fermi mixture of 174Yb-173Yb, experimentally observed recently, in the mean-field regime. In this mixture there is a possibility of tuning the Bose-Bose and Bose-Fermi interactions simultaneously using two well-separated optical Feshbach resonances, and it is a good candidate to explore phase separation in Bose-Fermi mixtures. Depending on the Bose-Bose scattering length aBB, as the Bose-Fermi interaction is tuned the density of the fermions is pinched or swapping with bosons occurs. [ABSTRACT FROM AUTHOR]

The mechanical deformation properties of nanostructured AgCo nanowires were studied by Molecular Dynamics (MD) under uniaxial tensile and compressive stresses. The cohesion of the immiscible AgCo system was modeled by an Embedded Atom Model (EAM). Crystalline Co grains were embedded into a Ag crystalline matrix and the whole system was set to relax by MD at 300 K. The Ag crystal structure turned out to be unstable and to transform into the same layered structure as was already predicted in AgCo nanoclusters and AgCo Cluster Assembled Materials (CAM). Deformation was modeled by varying the length of the nanowire in the axial direction. Both isothermal and isoenergetic—whereby mechanical work converts into heat in the system—deformation mechanisms were considered. In contrast with the case of AgCo CAM where an elastic regime was identified, deformation of AgCo nanowires was never found fully elastic, whatever the magnitude of the deformation. In case of constant temperature deformation, Ag kept its layered structure and the Co grains kept crystalline. At constant energy, as a consequence of the rise of temperature, phase separation and melting took place whereby a coaxial structure was formed with the Co covered by Ag. [Copyright &y& Elsevier]