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Simulationshave been performed using the free-energy binary-liquidlattice Boltzmann method with sufficient resolution that the criticalcapillary number for coalescence was determined for collisions betweendroplets in simple shear with a small initial offset in the sheargradient direction. The simulations were used to study the behaviorof the interacting interfaces and the film between them during collisionsover a wide range of capillary numbers with emphasis on near-criticalconditions. From these three-dimensional simulations with deforminginterfaces, several features of the evolution of the film betweenthe drops were observed. The critical film thickness was determinedto be similar to the interface thickness, a power law described thedependence of the minimum film thickness on the capillary number incollisions without coalescece, and an inflection point was found inthe dynamics of the minimum distance between drops that eventuallycoalesce. The rotation of the film and the flow in it were also studied,and a reversal in the flow was found to occur before coalescence.The mobility of the phase field was therefore important in the continuedthinning of the film at the points of minimum thickness after theflow reversal. A comparison of the critical capillary number and criticalfilm thickness in the simulations with the values for experimentsin confined simple shear indicated that the effective physical radiusof the simulated droplets was on the order of several micrometers.The results are significant for simulations of droplet interactionsand emulsion flows in complex geometries and turbulence because theydemonstrate the necessary scale of the computations and how parameters,such as the interface thickness and phase field mobility, should beselected for accurate results. [ABSTRACT FROM AUTHOR]

In natural fibre based-composites, the interfaces within the fibre bundles are not as well described as those between fibres and classical polymer matrices. To compensate for this lack of information, which is however of great importance when trying to model the composite behaviour, morphological and mechanical characterization of the middle lamella present between flax fibres has been carried out. The interfacial strength of the pectic cement was found to be very low compared with that of the fibre/matrix interface. Assuming this fibre/fibre interface to be a cohesive zone material and using the experimental results obtained on pairs of fibres, a model has been developed at the scale of the fibre and applied to study numerically the tensile properties of bundles. The results of the simulations were in agreement with the experimental data obtained on bundles, both leading to a mean bundle strength of 500 MPa. [ABSTRACT FROM PUBLISHER]

The quantum mechanical (QM)/molecular mechanical (MM) interface between Chemistry at HARvard Molecular Mechanics (CHARMM) and TURBOMOLE is described. CHARMM provides an extensive set of simulation algorithms, like molecular dynamics (MD) and free energy perturbation, and support for mature nonpolarizable and Drude polarizable force fields. TURBOMOLE provides fast QM calculations using density functional theory or wave function methods and excited state properties. CHARMM-TURBOMOLE is well-suited for extended QM/MM MD simulations using first principles methods with large (triple- ζ) basis sets. We demonstrate these capabilities with a QM/MM simulation of Mg2+(aq), where the MM outer sphere water molecules are represented using the SWM4-NDP Drude polarizable force field and the ion and inner coordination sphere are represented using QM PBE, PBE0, and MP2 methods. The relative solvation free energies of Mg2+ and Zn2+ were calculated using thermodynamic integration. We also demonstrate the features for excited state properties. We calculate the time-averaged solution absorption spectrum of indole, the emission spectrum of the indole [ABSTRACT FROM AUTHOR]

Nonequilibrium molecular dynamics (NEMD) simulations on conceptual binary Lennard-Jones systems show that the thermal conductivity (κ) of a superlattice (SL) can be significantly reduced by randomizing the thicknesses of its layers, by which a SL becomes a random multilayer (RML). Such reduction in κ is a clear signature of coherent phonon that can be localized in RMLs. We build a two-phonon model that divides the overall heat conduction into coherent and incoherent phonon contributions. In SL both coherent and incoherent phonons contribute to heat conduction, while in RML coherent phonons are localized so only incoherent phonons contribute. This model can fit the length dependence of the thermal conductances predicted in our NEMD simulations very well. The ballistic-limit thermal conductance and the intrinsic mean free path (MFP) of both coherent and incoherent phonons, and the localization length of coherent phonons, are obtained by fitting our model to the NEMD simulation results. The significant increase in κ of SL with total length is due to the long MFP of coherent phonons, and the lower κ of RML than SL is caused by the localization of coherent phonons. [ABSTRACT FROM AUTHOR]

We report surface tension measurements,coexisting densities, concentrationprofiles along the interfacial region, surface activities, and relativeGibbs adsorption isotherms for binary mixtures of carbon dioxide (CO2) + n-decane (n-C10H22) at 344.15 K and carbon dioxide (CO2) + n-eicosane (n-C20H42) at 323.15 K over a pressure range from 0.1 MPa to 10.35 MPa. Theresults are obtained by employing a broad approach that integratesexperiments with both theory and molecular simulations to gain anenhanced multiscale description of the interfacial region. Measurementsare based on the use of a high-pressure pendant drop tensiometer coupledto a high-pressure densimeter. Theoretical modeling is carried outusing the Square Gradient Theory based on a version of the StatisticalAssociated Fluid Theory (SAFT-VR Mie) equation of state. At the molecularlevel, Molecular Dynamics is employed and molecules are representedby the SAFT-γ coarse-grained force field. The novelty here isthat both the theory and the simulations uniquely share the same underlyingintermolecular potentials, hence the experimental data are employedto verify and inform in the same way both the theory and simulations.Reassuringly, theory, experiments, and molecular simulations agreewith each other in the description of the bulk phase equilibria andinterfacial tension. It is observed that for both mixtures, the interfacialtension decreases as the pressure (or the liquid mole fraction ofCO2) increases. Furthermore, there is quantitative agreementbetween the theoretical predictions and the results obtained fromthe molecular simulations of surface activities, concentration profilesalong the interfacial region, and relative Gibbs adsorption isothermsat the interfaces. A remarkable high excess adsorption of CO2, larger in eicosane than in decane, is detected along the interface. [ABSTRACT FROM AUTHOR]

We compare the simulations and measurements of gate leakage current in metal–insulator–semiconductor capacitors fabricated on standard AlGaN/GaN transistor layers. In the simulations, a fixed charge density at the interface between the Al2O3 layer and the GaN cap layer was assumed for simplicity. The fixed charge layer (which depends on bias and device history) was obtained from capacitance–voltage measurements. The calculated tunneling current due to field emission from localized states in the GaN cap layer agreed with the experimental results. No additional leakage mechanisms had to be invoked. [ABSTRACT FROM PUBLISHER]

This paper presents the technical solutions and methodologies that are used and under development for managing the design lifecycle of the WEST project (W – for tungsten – Environment in Steady-state Tokamak, upgrade of Tore Supra's with actively cooled tungsten plasma facing components) fusion components and explains the interfaces that are implemented or in construction to connect together the different tools like documents management system, CAD modeler, or simulation codes around the data management backbone. It describes the methodologies used on the WEST project to optimize the design process by managing the engineering data workflow and ensuring the consistency between the different 3D representations for design or analysis as well as the specification or interfaces documents. Finally it explains how this platform contributes to reach the project targets in terms of performance, cost and schedule. [ABSTRACT FROM AUTHOR]

The conceptual design of several gripping tools and their mechanical interfaces is being carried out for the ITER ECH UPP within the WP10-GOTRH programme. EFDA finances the GOT RH (Goal Oriented Training Programme for Remote Handling). The purpose of this paper is to introduce new concepts of gripping tools for the plug extraction/insertion in the upper port of ITER. All these gripping tools are designed according to IO input data and geometrical constraints. The gripping tools have to be able to extract/insert the plug in the scenario of maximum misalignment between the plug and the tractor. The paper also defines the functional requirements the gripping tools need to comply with. The requirements and input data are verified and validated through 3D simulation with Catia mock-ups of the gripping tools. The strengths and weaknesses of each gripping tool model are compared. [ABSTRACT FROM AUTHOR]

To obtain a molecular level viewof the interface of a latex particlewith water solvent, atomistic simulations using two different forcefields were performed for a slab of methyl methacrylate (MMA)/n-butyl acrylate (BA) random copolymer in water. The carbonylgroups at the polymer/water interface were found to orient significantlytoward the water phase. We calculated the copolymer/water and thecopolymer/vacuum interfacial tensions, and predict a contact anglefor water on copolymer of 77°, consistent with experimental values.We also calculated bulk densities of MMA/BA copolymer, and PMMA andPBA homopolymers, which compare well with experiment, and the structurefactor for PMMA, which agrees with neutron scattering results. Thesimulated Tgof PMMA is not far from itsexperimental value, despite the much shorter chains and faster coolingrates of simulations versus experiments, because these two effectstend to cancel each other. When we correct for these effects, thepredicted Tgis within 5 K of the experimentalvalue. [ABSTRACT FROM AUTHOR]

The optical spectrum of the hydrated(aqueous) electron, eaq–, is theprimary observable by means of which this species is detected, monitored,and studied. In theoretical calculations, this spectrum has most oftenbeen simulated using one-electron models. Here, we present ab initiosimulations of that spectrum in both bulk water and, for the firsttime, at the water/vapor interface, using density functional theoryand its time-dependent variant. Our results indicate that this approachprovides a reliable description, and quantitative agreement with theexperimental spectrum for the bulk species is obtained using a “tuned”long-range corrected functional. The spectrum of the interfacial electronis found to be very similar to the bulk spectrum. [ABSTRACT FROM AUTHOR]

Interdiffusion microstructure maps (IMMs) are drawn on isothermal phase diagrams. They predict how the interdiffusion microstructure varies in a dual alloy when one alloy composition is fixed while the other is varied across a region of the phase diagram. The microstructure is defined in terms of its layers and the velocity direction of boundaries between layers. Previous work involved maps based on experimental, calculated and simulated interdiffusion microstructures. In the current work IMMs for four model systems were obtained from phase field simulations. The IMMs in this study differ from previous work in that one contains a more complicated IMM with seven areas separated by seven lines that meet at a seven-line node and one contains a less complicated IMM with only one area. Also, it was found that the microstructures at all nodes investigated to date are similar by having the microstructure of the initial dual alloy. During interdiffusion treatments the initial interface is stationary and only the amounts of phases on either side of the interface will vary with time. A list of fundamental properties of IMMs is given that combines findings from the current and previous work. In the list are three mechanisms by which microstructures change. One of these had not been seen before. In this mechanism an inversion of the microstructure occurs as the composition crosses from one side to the other of a two-phase region. These fundamentals are the foundation on which IMMs are constructed and can be a guide for their interpretation. [ABSTRACT FROM AUTHOR]

Hot stamping tools with cooling systems are key facilities for hot stamping processes in the automotive industry. In hot stamping, the tools are heated by workpieces and rapidly cooled by cooling water. The thermal deformation of the tools has a significant influence on the properties of the hot stamped parts and the useful life of the tools. In this paper, a multi-field simulation method is proposed for analysis of deformation in the tools. Based on a mesh based parallel code coupling interface, a thermal-fluid-mechanical coupled model is established to analyse the cooling effect and the deformation of the tools. The experimental set-up was built to verify the multi-field coupling model. It is shown that the cooling rate of the hot stamped part was 217°C s−1, higher than the critical cooling rate of 30°C s−1. The temperature history of the hot formed part was in good agreement with the experimental result. The cooling ducts were deformed because of the thermal expansion of the hot tools. This led to stress concentration at the rectangular corner of the ducts. The speed of cooling water flow increased by 112% through the bottom ducts, while at the corners of the ducts, the speed was very low and a 'hot spot' appeared. [ABSTRACT FROM AUTHOR]

Several examples illustrating the energy balance associated with a mixing process at the interface of a planar dynamical model describing two-phase perfect fluid circulating around a circle with a sufficiently large radius within a central gravitational field are presented. The model is associated with the spatial and temporal structure of the zonally averaged global-scale atmospheric longitudinal circulation around the Earth. The fluid is supposed to be irrotational and pressure on a outer layer is constant. It is postulated that the total fluid depth is small compared to the radius of the circle and the gravity vector is directed to the center of the circle. Under these assumptions, this problem can be associated with a spatial and temporal structure of the zonally averaged global-scale atmospheric longitudinal circulation around equatorial plane. The model is the subject to the rigid lid approximation to the external boundary conditions for the outer fluid layer. One of the novelties in this work is the derivation of the nonlinear shallow water model by means of the average velocity. This introduction simplifies essentially further potential studies of mixing criteria associated with nonlinear mathematical models representing shallow water equations [ABSTRACT FROM AUTHOR]

Abstract: Galilean invariance is a fundamental property; however, although the dynamics of lattice Boltzmann equation in the hydrodynamic limit is Galilean invariant, this property is usually not taken into account in the treatment of the fluid–solid interface. Here, we show that consideration of Galilean invariance in fluid–solid interfacial dynamics can greatly enhance the computational accuracy and robustness in a numerical simulation. Surprisingly, simulations are so vastly improved that the force fluctuation is very small and a time average becomes unnecessary. [Copyright &y& Elsevier]

Models of moving interfaces, especially those with stable soliton-like behavior, are of central importance in many areas of physics, for example, surface growth models, chemical waves, and more. Here described for the first time in a realistic geophysical context is a partial differential equation model of bedrock abrasion by unidirectional impacts generalizing earlier pioneering work on pebble shapes by Bloore who treated isotropic impacts (Bloore in Math. Geol. 9:113-122, ). The result is a simple geometrical partial differential equation exhibiting circular arcs as solitary wave profiles. The latter seem to be the first known analytic solutions on Bloore-type models. Solitonic behavior, although familiar in many areas of physics, appears not to have been encountered in the geophysical literature. Not only are the existence and stability of these stationary, traveling shapes demonstrated here by numerical experiments based on finite difference approximations, but it is also shown that the results received here are consistent with recent laboratory experiments. The simulations within show that, depending on initial profile shape and other parameters, these circular profiles may evolve via long transients, which in a geological setting, may appear as noncircular stationary profiles. [ABSTRACT FROM AUTHOR]

Highlights: [•] An innovative pyrolysis reactor was proposed for waste plastics. [•] Molten plastic pyrolysis proceeds in form of vertical falling film evaporation. [•] The liquid film interface features wavier at higher heating temperature. [•] The fluid temperature rises with the increase of the heating temperature. [•] The molar concentration of volatile is higher in the lower region of the reactor. [ABSTRACT FROM AUTHOR]

Abstract: The interface thickness is the most crucial parameter in the phase field model (PFM) for the accuracy and the computability. However, the Gibbs–Thomson equation can be satisfied only when the interface thickness is sufficiently small, especially with a large undercooling, but this greatly limits the applications of PFM to a realistic problem. The temperature correction in the thin-interface model partially resolves the problem, but the range is rather limited. In this report, we propose a new formulation of PFM by adding extra terms stabilizing the hyperbolic tangent profile of the phase-field, and this allows us to use a much larger interface thickness for simulation, even with a large undercooling. Several benchmark comparisons with analytical solutions are carried out and discussed. [Copyright &y& Elsevier]

Abstract: This paper presents a new haptic rate-position controller, which allows manipulating a slave robot in a large workspace using a small haptic device. This control algorithm is very effective when the master device is much smaller than the slave device. Haptic information is displayed to the user so as to be informed when a change in the operation mode occurs. This controller allows performing tasks in a large remote workspace by using a haptic device with a reduced workspace such as Phantom. Experimental results have been carried out using a slave robot from Kraft Telerobotics and a commercial haptic interface as a master device. A curvature path following task has been simulated using the proposed controller which was compared with the force-position control algorithm. Results obtained show that higher accuracy is obtained when the proposed method is used, spending a similar amount of time to perform the task. [Copyright &y& Elsevier]

A shock tube facility for generating a cylindrical converging shock wave is developed in this work. Based on the shock dynamics theory, a specific wall profile is designed for the test section of the shock tube to transfer a planar shock into a cylindrical one. The shock front in the converging part obtained from experiment presents a perfect circular shape, which proves the feasibility and reliability of the method. The time variations of the shock strength obtained from numerical simulation, experiment, and theoretical estimation show the desired converging effect in the shock tube test section. Particular emphasis is then placed on the problem of shock-interface interaction induced by cylindrical converging shock waves. For this purpose, membrane-less gas cylinder is adopted to form the interface between two different fluids while the laser sheet technique to visualize the flow field. The result shows that it is convenient to perform such experiments in this facility. [ABSTRACT FROM AUTHOR]

Highlights: [•] Cracked plain and steel fibre reinforced concrete flexural beams were investigated. [•] “Instrumented rebars” provided location- and time-dependent corrosion measurements. [•] Interfacial condition can be used as a reliable indicator to quantify the risk of corrosion. [•] Simulated interfacial conditions are in very good agreement with all experimental observations. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a modeling methodology for field bus-based embedded systems that allows dynamic evaluation of their signal integrity characteristics at the virtual prototyping step. Our methodology is based on the following criteria: 1) a signal integrity-aware I/O interface mixed model; 2) a physical model of transmission lines to estimate signal degradation caused by the bus lines; and 3) an ICEM model to estimate the impact of a chip's internal activity on its power voltage or its I/O. Through simulations and experimental validations, we show that our methodology allows functional validation of the design and can also evaluate some low-level effects such as the influence of an embedded software instruction on the voltage drops in the power rails. [ABSTRACT FROM PUBLISHER]

Sliding at interface during thin film buckling was reported by recent atomistic simulations. A stability analysis under the Föppl-von Kármán plate theory is performed to investigate the effect of interface sliding on the transition of a straight-sided blister to the telephone cord buckle in biaxially compressed thin films on rigid substrates. It is shown that the critical stress and the wavelength of the telephone cord buckle significantly increase as the interface sliding is noticeable in comparison with the constant values derived from previous classic analysis without interface sliding. Our theoretic analysis is further validated by results from numerical simulations based on our recently developed continuum model of nonlinear buckling. The results indicate that the wavelength variation in the telephone cord buckle observed in experiments may be due to interface sliding. [ABSTRACT FROM AUTHOR]

Previous experiments and simulationshave shown that acetonitrileorganizes into a lipid-like bilayer at the liquid/silica interface.Recent simulations have further suggested that this bilayer structurepersists in mixtures of acetonitrile with water, even at low acetonitrileconcentrations. This behavior is indicative of microscopic phase separationof these liquids near silica interfaces and may have important ramificationsfor the use of acetonitrile in chromatography and heterogeneous catalysis.To explore this phenomenon, we have used vibrational sum-frequency-generationspectroscopy to probe acetonitrile/water mixtures at a silica interface.Our spectraprovide evidence that acetonitrile partitions to the hydrated silicainterface even when the mole fraction of acetonitrile is as low as10%. A blue shift is observed in the spectrum of the methyl symmetricstretch upon increasing water mole fraction, in agreement with vibrationalspectra of bulk mixtures. Line shape analysis suggests that acetonitrilemay exist in the form of bilayer patches at high water mole fractions. [ABSTRACT FROM AUTHOR]

Highlights: [•] This paper presents a micromechanics-based approach to the interface modeling in metal forming. [•] It catches the nature of friction and heat transfer and implements together both models. [•] We give insight into how a process designer could evaluate a candidate tooling design. [•] Chilling due to better heat transfer leads to increased resistance to deformation. [•] The model gives qualitatively and quantitatively promising results for many combinations. [ABSTRACT FROM AUTHOR]

Abstract: A new, simple, and computationally efficient interface capturing scheme based on a diffuse interface approach is presented for simulation of compressible multiphase flows. Multi-fluid interfaces are represented using field variables (interface functions) with associated transport equations that are augmented, with respect to an established formulation, to enforce a selected interface thickness. The resulting interface region can be set just thick enough to be resolved by the underlying mesh and numerical method, yet thin enough to provide an efficient model for dynamics of well-resolved scales. A key advance in the present method is that the interface regularization is asymptotically compatible with the thermodynamic mixture laws of the mixture model upon which it is constructed. It incorporates first-order pressure and velocity non-equilibrium effects while preserving interface conditions for equilibrium flows, even within the thin diffused mixture region. We first quantify the improved convergence of this formulation in some widely used one-dimensional configurations, then show that it enables fundamentally better simulations of bubble dynamics. Demonstrations include both a spherical-bubble collapse, which is shown to maintain excellent symmetry despite the Cartesian mesh, and a jetting bubble collapse adjacent a wall. Comparisons show that without the new formulation the jet is suppressed by numerical diffusion leading to qualitatively incorrect results. [Copyright &y& Elsevier]

Abstract: A momentum jump condition is derived which models the influence of surface active agents at fluid interfaces due to Marangoni stresses. Underlying assumptions are quasi-stationary shape and surfactant distribution. The model is simple to implement into sharp interface two-phase flow solvers and VOF-based numerical simulations show that the effect of the jump condition is comparable to stagnant cap type models for small bubbles. An explicit cap angle is not needed, making it applicable to non-symmetric interface geometries, where a cap angle is hard to define. This approach via a modified interfacial momentum jump condition is also suitable for Front tracking or Level Set methods. [Copyright &y& Elsevier]

Highlights: [•] A modeling architecture was proposed for pyroprocessing plant-level simulator. [•] We solved an interface issue between continuous and discrete event systems. [•] Models built from different languages could be incorporated into one platform. [•] We designed database for pyroprocessing model according to data classifications. [•] Two pyroprocessing sample models verify the modeling architecture related issues. [Copyright &y& Elsevier]

A finite element framework of a phase field model for nanoscale martensitic transformation is proposed on the basis of time-dependent Ginzburg-Landau kinetic equations. The bulk total free energy consists of the chemical driving energy, the interfacial energy, the elastic energy, the inertial energy (for a dynamic case), the energy due to applied field and the effects of surface energy which need to be considered at the nanoscale. Single-variant and multi-variant martensitic phase transformations in a nano-sized NiAl plate are considered. The numerical results show the effects of each energy item on the phase transformation and the self-accommodating twinned morphologies as the result of strain energy minimization. [ABSTRACT FROM AUTHOR]

An investigation of fatigue crack growth of interfacial cracks in bi-layered materials using the extended finite element method is presented. The bi-material consists of two layers of dissimilar materials. The bottom layer is made of aluminium alloy while the upper one is made of functionally graded material (FGM). The FGM layer consists of 100 % aluminium alloy on the left side and 100 % ceramic (alumina) on the right side. The gradation in material property of the FGM layer is assumed to be exponential from the alloy side to the ceramic side. The domain based interaction integral approach is extended to obtain the stress intensity factors for an interfacial crack under thermo-mechanical load. The edge and centre cracks are taken at the interface of bi-layered material. The fatigue life of the interface crack plate is obtained using the Paris law of fatigue crack growth under cyclic mode-I, mixed-mode and thermal loads. This study reveals that the crack propagates into the FGM layer under all types of loads. [ABSTRACT FROM AUTHOR]

A NURBS enhanced extended finite element approach is proposed for the unfitted simulation of structures defined by means of CAD parametric surfaces. In contrast to classical X-FEM that uses levelsets to define the geometry of the computational domain, exact CAD description is considered here. Following the ideas developed in the context of the NURBS-enhanced finite element method, NURBS-enhanced subelements are defined to take into account the exact geometry of the interface inside an element. In addition, a high-order approximation is considered to allow for large elements compared to the size of the geometrical details (without loss of accuracy). Finally, a geometrically implicit/explicit approach is proposed for efficiency purpose in the context of fracture mechanics. In this paper, only 2D examples are considered: It is shown that optimal rates of convergence are obtained without the need to consider shape functions defined in the physical space. Moreover, thanks to the flexibility given by the Partition of Unity, it is possible to recover optimal convergence rates in the case of re-entrant corners, cracks and embedded material interfaces. [ABSTRACT FROM AUTHOR]

This work reports a computer modeling comparison of two solid electrolyte materials, Li3PO4 and Li3PS4, in terms of the bulk structures, Li ion mobilities, and their interface properties with vacuum and with Li metal. The simulations show that for some forms of Li3PS4, Li ions can move from a host lattice site to an interstitial site with negligible net energy change. This favorable process for the formation of vacancy-interstitial pairs is undoubtedly important for the structural and ion migration properties of β-Li3PS4. Our model results for the idealized interfaces between the electrolytes and Li metal show that Li3PO4 /Li interfaces are stable, while Li3PS4 /Li interfaces are not. We find that a Li3PS4 surface in the presence of a small amount of Li relaxes to a complicated structure involving broken P-S bonds. On the other hand, the computer models show that a very thin film of Li2S on the Li3PS4 surface can provide a protective buffer layer to stabilize the interface between the Li3PS4 electrolytes and the Li metal anode [ABSTRACT FROM AUTHOR]

A micromechanical model is developed to simulate the evolution of microstructure during in-service sintering and eventual inter-columnar cracking in coatings made using electron beam vapour deposition (EB-PVD) route. The coating is idealized with a discrete distribution of axisymmetric asperities across interfaces between columnar grains. The model assumes that inter-columnar sintering is driven by changes in interface free energy of columns and the potential energy of the applied stress. Much faster diffusion that occurs over the free surfaces of the asperities is neglected. It is further assumed that the rate of sintering of the contacting asperities is determined by diffusion along the interface between the contacting asperities. Time evolution of contact modulus of the coating is accounted for as a function of sintering strain. The developed macroscopic constitutive model is employed to evaluate the sensitivity of the sintering response to imperfections and examine the conditions under which inter-columnar cracks can develop within the coating. [ABSTRACT FROM AUTHOR]

On the basis of transformation optics, we propose an approach to couple surface plasmon waves across gaps in a dielectric/metal interface. The coupler employs a slab of complementary medium with negative refraction index to virtually bridge the gap by optically compensating the rest air region in the gap. Several design examples through transformation optics have been demonstrated which could enable plasmonic waves to propagate through two-dimensional gaps in metal surfaces with transversal offset, vertical offset or tilt geometry. The functionality of the proposed couplers has been validated through finite-element method-based full-wave simulations. [ABSTRACT FROM AUTHOR]