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• A novel holly-leaf shaped graphene (HLG) with unique hollowed-out structure has been designed. • A possible formation mechanism of HLG has been demonstrated that strong capillary forces from wood arrayed pore structure plays a crucial role. • Both experiment and theoretical model demonstrate its structural superiority in facilitating photothermal conversion. • HLG/wood has excellent performance for seawater desalination and sewage treatment. Similar to transpiration, the formulation of interfacial solar evaporation has been designed to perform water treatment. The concept involves wood-based support (tree) with a graphene-based layer acting as leaves. To enhance light absorption and solar-thermal conversion capacity, a novel holly-leaf graphene (HLG) layer with an individual hollowed-out structure was engineered. The formation mechanism of this HLG was shown to be linked to the strong capillarity forces in the polyporous wood. By creating biomimetic leaves made of graphene, the light-to-heat conversion performance can be improved, while exhibiting substantially lower thermal conductivity (0.074 W/(m K)) than natural wood. Under solar irradiation, HLG/wood exhibits an outstanding evaporation rate of 1.96 kg/(m2 h), with an impressive efficiency of 94.2 %. A theoretical model of HLG/wood based on the thermal management capability was built to further confirm its structural superiority in facilitating photothermal conversion. Consequently, a bilayer evaporator based on HLG/wood has the potential to revolutionize water purification processes, including desalination of seawater, removal of heavy metal ions, and treatment of organic dye-contaminated wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Axisymmetric beading instabilities in soft, elongated cylinders have been observed in a plethora of scenarios, ranging from cellular nanotunnels and nerves in biology to swollen cylinders and electrospun fibers in polymer physics. One of the common geometrical features that can be seen in these systems is the finite wavelength of the emerging pattern. However, modelling studies often predict that the instability has an infinite wavelength, which can be associated with localized necking or bulging. In this paper, we consider a soft elastic cylinder with a thin coating that resists bending, as described by the Helfrich free energy functional. The bending stiffness and natural mean curvature of the coating are two novel features whose competition against bulk elasticity and capillarity is investigated. For intermediate values of the bending stiffness, a linear stability analysis reveals that the mismatch between the current and natural mean curvature of the coating can lead to patterns emerging with a finite wavelength. This analysis creates a continuous bridge between the classical solutions of the shape equation obtained from the Helfrich functional and a curvature-controlled zero-wavemode instability, similar to the one induced by the competition between bulk elasticity and capillarity. A weakly non-linear analysis predicts that the criticality of the bifurcation depends on the controlling parameter, with both supercritical and subcritical bifurcations possible. When capillarity is introduced, the criticality of the bifurcation changes in a non-trivial way. • We study axisymmetric beading in elastic cylinders with a thin coating. • Curvature incompatibility can lead to patterns emerging with finite wavelength. • Highly curved coatings lead to an infinite-wavelength elastocapillary-like pattern. • The emerging pattern can have localized amplitude modulations. • The pattern can be controlled by stretching, bending, and capillarity. [ABSTRACT FROM AUTHOR]

Some errors exist in the above paper. [ABSTRACT FROM AUTHOR]

Bioengineering, Biomedical Engineering, Biomedicine, Biotechnology, Health and Medicine, Tissue Engineering Keywords: Bioengineering; Biomedical Engineering; Biomedicine; Biotechnology; Health and Medicine; Tissue Engineering EN Bioengineering Biomedical Engineering Biomedicine Biotechnology Health and Medicine Tissue Engineering 304 304 1 07/10/23 20230713 NES 230713 2023 JUL 13 (NewsRx) -- By a News Reporter-Staff News Editor at Blood Weekly -- Investigators discuss new findings in tissue engineering. [Extracted from the article]

In this study, we present lattice Boltzmann simulations of two-phase immiscible displacements driven by constant pressure differentials. The method to implement the pressure boundary condition is based on bounce-back of the total non-equilibrium distribution. Simulations show that phase and pressure distributions are consistent with the imposed pressure boundaries. The accuracy was verified by simulating flows in a capillary tube, a problem with a moving interface for which an analytical solution is available. Following the verification, we simulated two-phase immiscible displacements in a random sphere packing and characterized the effects of capillary number, viscosity ratio, and wettability on the dynamics of displacement and the relative permeability. [ABSTRACT FROM AUTHOR]

In this paper, a three-dimensional phase-field lattice Boltzmann method is used to simulate the dynamical behavior of a droplet, subject to an outer viscous flow, in a microchannel that contains a cylindrical hole etched into its top surface. The influence of the capillary number and the hole diameter (expressed as the ratio of hole diameter to channel height, b ) is investigated. We demonstrate numerically that the surface energy gradient induced by the hole can create an anchoring force to resist the hydrodynamic drag from the outer flow, resulting in the droplet anchored to the hole when the capillary number is below a critical value. As b increases, the droplet can be anchored more easily. For b < 2, the droplet partially enters into the hole and forms a spherical cap; whereas for b > 2, the spherical cap of droplet reaches the top wall of the hole, making the hole depth into an additional important parameter. These observations are consistent with the previously reported experiments. However, the droplet does not fully fill the hole for b > 2, departing from the expectation of Dangla et al. [R. Dangla, S. Lee, C. N. Baroud, Trapping microfluidic drops in wells of surface energy, Phys. Rev. Lett. 107 (2011) 124501]. Also, it is observed in the anchored state that the rear of the droplet rests at a small distance away from the junction. Finally, the droplet undergoes a slow-down process only when its rear passes through the hole, regardless of b . [ABSTRACT FROM AUTHOR]

This paper deals with a novel formulation of a nonlinear reduced-order computational model for analyzing the nonlinear vibrations of a linear viscoelastic structure with weak nonlinear geometrical effects, coupled with a linear acoustic liquid with sloshing and capillarity on the free surface. The model proposed is derived from the one used in fluid-structure interaction for linear systems, for which the analysis of the acoustic-sloshing-capillarity phenomena is efficient thanks to the use of a projection on the linear modes of the linear acoustic liquid and on the sloshing modes with capillarity. Concerning the construction of the vector basis for the structure, it is proposed to use a POD approach for the viscoelastic structure with weak nonlinear geometrical effects and taking into account the added mass induced by the liquid. The methodology for constructing the vector bases of the admissible sets and for obtaining the nonlinear ROM are detailed. The computational nonlinear ROM that is presented can directly be used for analyzing the vibrations of such fluid-structure systems using commercial finite element softwares for computing the vector bases and the projections. [ABSTRACT FROM AUTHOR]

In this paper we consider a multiscale phase-field model for capillarity-driven flows in porous media. The presented model constitutes a reduction of the conventional Navier–Stokes–Cahn–Hilliard phase-field model, valid in situations where interest is restricted to dynamical and equilibrium behavior in an aggregated sense, rather than a precise description of microscale flow phenomena. The model is based on averaging of the equation of motion, thereby yielding a significant reduction in the complexity of the underlying Navier–Stokes–Cahn–Hilliard equations, while retaining its macroscopic dynamical and equilibrium properties. Numerical results are presented for the representative 2-dimensional capillary-rise problem pertaining to two closely spaced vertical plates with both identical and disparate wetting properties. Comparison with analytical solutions for these test cases corroborates the accuracy of the presented multiscale model. In addition, we present results for a capillary-rise problem with a non-trivial geometry corresponding to a porous medium. [ABSTRACT FROM AUTHOR]

A poromechanical model of partially saturated deformable porous media is proposed based on a phase field approach at modeling the behavior of the mixture of liquid water and wet air, which saturates the pore space, the phase field being the saturation (ratio). While the standard retention curve is expected still^ to provide the intrinsic retention properties of the porous skeleton, depending on the porous texture, an enhanced description of surface tension between the wetting (liquid water) and the non-wetting (wet air) fluid, occupying the pore space, is stated considering a regularization of the phase field model based on an additional contribution to the overall free energy depending on the saturation gradient. The aim is to provide a more refined description of surface tension interactions. An enhanced constitutive relation for the capillary pressure is established together with a suitable generalization of Darcy's law, in which the gradient of the capillary pressure is replaced by the gradient of the so-called generalized chemical potential, which also accounts for the “force”, associated to the local free energy of the phase field model. A micro-scale heuristic interpretation of the novel constitutive law of capillary pressure is proposed, in order to compare the envisaged model with that one endowed with the concept of average interfacial area. The considered poromechanical model is formulated within the framework of strain gradient theory in order to account for possible effects, at laboratory scale, of the micro-scale hydro-mechanical couplings between highly localized flows (fingering) and localized deformations of the skeleton (fracturing). [ABSTRACT FROM AUTHOR]

Core-shell nanowires with radial heterostructures hold great promise in photonic and electronic applications and controlling the formation of these heterostructures in the core-shell conguration remains a challenge. Recently, GaAs nanowires have been used as substrates to create AlGaAs shells. The deposition of the AlGaAs layer leads to the spontaneous formation of Al-rich stripes along certain crystallographic directions and quantum dots near the apexes of the shell. A general two-dimensional model has been developed for the motion of the faceted solid-vapor interfaces for pure materials that accounts for capillarity and deposition. With this model, the growth processes and morphological evolution of shells of nanowires around hexagonal cores (six small facets {112} in the corners of six equivalent facets {110}) are investigated in detail both analytically and numerically. It is found that deposition can yield facets that are not present on the Wulff shape. These small facets can have slowly time-varying sizes that can lead to stripe structures and quantum dots depending on the balances between diffusion and deposition. The effects of deposition rates and polarity (or asymmetry) on planes {112} on the development of the configurations of nanowires are discussed. The numerical results are compared with experimental results giving almost quantitative agreement, despite the fact that only pure materials are treated herein whereas the experiments deal with alloys. [ABSTRACT FROM AUTHOR]

Comparison of the transmission of 27-keV Ar 9+ ions through insulating funnel- and conical-shaped glass capillaries of outlet diameters of ~22 µm is reported. Beam intensities of 1, 5, and 10 pA were injected into both capillaries. Transmission at the untilted angle of 0° was measured as well as at a tilt angle of ~0.5° for the funnel capillary and a tilt angle of ~1.1° for the conical capillary. For the funnel capillary, blocking of transmission was observed, whereas, the transmission was continuous for the conical capillary. These measurements suggest that conical-shaped capillaries have transport properties that are different than funnel-shaped capillaries for slow highly charged ions. [ABSTRACT FROM AUTHOR]

Abstract: We present a combined theoretical and experimental study of the buckling of a thin film wrapped around a sphere under the action of capillary forces. A rigid sphere is coated with a wetting liquid, and then wrapped by a thin film having an approximately cylindrical shape. The equilibrium of the film is governed by the competing effects of elasticity and capillarity: elasticity tends to keep the film developable while capillarity tends to curve it in both directions so as to maximize the area of contact with the sphere. In the experiments, the region of contact between the film and the sphere has cylindrical symmetry when the sphere radius is small, but destabilizes to a non-symmetric, wrinkled configuration when the radius is larger than a critical value. We combine the Donnell equations for near-cylindrical shells to include a unilateral constraint with the impenetrable sphere, and the capillary forces acting along a moving edge. A non-linear solution describing the axisymmetric configuration of the film is derived. A linear stability analysis is then presented, which successfully captures the wrinkling instability, the symmetry of the unstable mode, the instability threshold and the critical wavelength. The motion of the free boundary at the edge of the region of contact, which has an effect on the instability, is treated without any approximation. [Copyright &y& Elsevier]

Abstract: An ensemble-based method has been developed and successfully applied to simultaneously estimate relative permeability and capillary pressure curves for tight formations by history matching the measurement data. The power-law and B-spline models are first used to represent the relative permeability and capillary pressure curves, respectively. Then, parameters of such two models are tuned automatically and finally determined once the measurement data is assimilated completely and history matched. The estimation of relative permeability and capillary pressure has been found to improve progressively and the corresponding uncertainties are mitigated gradually as more measurement data is assimilated. As assimilation of the measurement data is completed, an excellent agreement has been found between the updated and reference relative permeability and capillary pressure curves, though estimation accuracy suffers slightly when B-spline interpolation is used. Among all the to-be-estimated parameters, the endpoint of the capillary pressure curve shows its compromising accuracy, depending on its initial value. [Copyright &y& Elsevier]

Abstract: The dynamics of the Reynolds stress tensor for turbulent flows is described with an evolution equation coupling both geometric effects and turbulent source terms. The effects of the mean flow geometry are shown up when the source terms are neglected: the Reynolds stress tensor is then expressed as the sum of three tensor products of vector fields which are governed by a distorted gyroscopic equation. Along the mean flow trajectories, the fluctuations of velocity are described by differential equations whose coefficients depend only on the mean flow deformation. If the mean flow vorticity is small enough, an approximate turbulence model is derived, and its application to shear shallow water flows is proposed. Moreover, the approximate turbulence model admits a variational formulation which is similar to the one of capillary fluids. [Copyright &y& Elsevier]

In this Brief Report, we observed the dynamic guiding of 10-keV O- ions (50 pA/mm2) transmitting through A12O3 nanocapillaries. The transmitted O- ions shift gradually to the direction of the capillary axis, and the angular FWHM also increases significantly. However, the transmission rate of O- ions decreases. The data imply that the charges deposited in capillaries provide a sufficient guiding force to the incident O- ions. [ABSTRACT FROM AUTHOR]

Abstract: The nonlinear capillary instability of the cylindrical interface between the vapor and liquid phases of a fluid is studied when there is heat and mass transfer across the interface, using viscous potential flow theory. The fluids are considered to be viscous and incompressible with different kinematic viscosities. Both asymmetric and axisymmetric disturbances are considered. The analysis is based on the method of multiple scale perturbation and the nonlinear stability is governed by first-order nonlinear partial differential equation. The stability conditions are obtained and discussed theoretically as well as numerically. Regions of stability and instability have been shown graphically indicating the effect of various parameters. It has been observed that the heat and mass transfer has stabilizing effect on the stability of the system in the nonlinear analysis for both axisymmetric as well as asymmetric disturbances. [Copyright &y& Elsevier]

Abstract: The capillary attraction of two parallel cylinders with circular cross-section representing slender particles floating at the interface between two immiscible fluids is considered. Given the particle separation, the elevation of the particle centers in hydrostatics is computed to satisfy the vertical force balance involving the buoyancy force, the capillary force, and the particle weight. A numerical procedure is developed for calculating the horizontal force exerted on a pair of cylinders in solitary or periodic arrangement. The results confirm that the particles attract each other under the conditions considered. The particle motion and transient flow due to the particle attraction are computed using a boundary-integral method for Stokes flow. In the algorithm, the particle center velocity of translation and angular velocity of rotation are calculated to satisfy force and torque balances. Numerical simulations using a boundary-element method subject to an initial state provided by hydrostatics illustrate the nature of the motion and furnish estimates for the particle velocity induced by capillarity. [Copyright &y& Elsevier]

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We describe a method to measure and correct for the incoherent component of energy flow arising from multiple interactions from jet shape and substructure observables of massive jets. The correction is a function of the jet-shape variable of interest and not a universal property. Such a correction is expected to reduce biases in the corresponding distributions generated by the presence of multiple interactions and to improve measurement resolution. This data-driven technique is not subject to uncertainties coming from the use of theoretical calculations. Corrections are derived for jet mass, angularity, and planar flow, and are tound to be in good agreement with data on massive jets observed by the CDF collaboration. Finally, we comment on the linkage with the concept of jet area and jet mass area. [ABSTRACT FROM AUTHOR]

Abstract: Plane steady-state seepage in a homogeneous isotropic ground from channels through a layer of soil with an underlying highly permeable pressurized water-bearing layer when the ground possesses capillarity and there is evaporation from the free surface is considered in a hydrodynamic formulation. To investigate it, a mixed multiparametric boundary-value problem of the theory of analytical functions is formulated, which is solved using the Polubarinova-Kochina method and conformal mapping of the regions of a special form, typical of problems of underground hydromechanics. On the basis of this model, an algorithm for calculating the capillary spreading of water and seepage flow is developed in situations when the ground capillarity is taken into account in the seepage of water from channels, as well as evaporation from the free surface of the ground waters, and also backwater of the underlying highly permeable stratum. Using the exact analytical relations obtained and numerical calculations, a hydrodynamic analysis of the structure and characteristic features of the simulated process, and also of the effect of all the physical parameters of the system on the seepage characteristics, is carried out. Limit and special cases, related to the absence of one or two of the three factors, characterizing the simulated process are considered: the ground capillarity, evaporation from the free surface, and also backwater of the underlying highly permeable water-bearing layer. The results of the calculations are compared with similar seepage characteristics with a similar scheme, but in which the flow region is underlaid by an impenetrable base. [Copyright &y& Elsevier]

Abstract: The study of two phase flow in porous media under high capillary pressures, in the case where one phase is incompressible and the other phase is gaseous, shows complex phenomena. We present in this paper a numerical approximation method, based on a two pressures formulation in the case where both phases are miscible, which is shown to also handle the limit case of immiscible phases. The space discretization is performed using a finite volume method, which can handle general grids. The efficiency of the formulation is shown on three numerical examples related to underground waste disposal situations. [Copyright &y& Elsevier]

Abstract: Underfill is an important process in flip-chip encapsulation because of its great impact on the reliability of the electronic packagings. This paper focuses on the study of the fluid flow in capillary-driven underfill encapsulation, and a three-dimensional simulation approach of the underfill process is proposed. Firstly, the driven mechanism of the capillary action is analyzed by first presenting an inter-motivation model, according to which the capillary action is modeled as two different forces, the adhesive tension force close to the wall and the surface tension force on the free surface. Those two forces motivate each other during the fluid flow process. Then, based on this, the fluid flow simulation of the underfill process is established. During the solution, two common Petrov–Galerkin (PG) methods are employed to solve the governing equations. Finally, the piecewise linear interface calculation (PLIC)-flow analysis network (FAN) method is proposed to track and reconstruct the melt-front for each time step. Compared with the experimental data and the predictions of the other numerical methods, the proposed approach shows a good performance in predicting the fluid flow in the capillary-driven underfill process. [Copyright &y& Elsevier]

Two theoretical descriptions of exclusive diffractive jets and Higgs production at the LHC were implemented into the FPMC generator: the Khoze, Martin, Ryskin model and the Cudell, Hernández, lvanov, Dechambre exclusive model. We then study the uncertainties. We compare their predictions to the CDF measurement and discuss the possibility of constraining the exclusive Higgs production at the LHC with early measurements of exclusive jets. We show that the present theoretical uncertainties can be reduced with such data by a factor of 5. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present an efficient numerical method for two-phase immiscible flow in porous media with different capillarity pressures. In highly heterogeneous permeable media, the saturation is discontinuous due to different capillary pressure functions. One popular scheme is to split the system into a pressure and a saturation equation, and to apply IMplicit Pressure Explicit Saturation (IMPES) approach for time stepping. One disadvantage of IMPES is instability resulting from the explicit treatment for capillary pressure. To improve stability, the capillary pressure is usually incorporated in the saturation equation which gradients of saturation appear. This approach, however, does not apply to the case of different capillary pressure functions for multiple rock-types, because of the discontinuity of saturation across rock interfaces. In this paper, we present a new treatment of capillary pressure, which appears implicitly in the pressure equation. Using an approximation of capillary function, we substitute the implicit saturation equation into the pressure equation. The coupled pressure equation will be solved implicitly and followed by the explicit saturation equation. Five numerical examples are provided to demonstrate the advantages of our approach. Comparison shows that our proposed method is more efficient and stable than the classical IMPES approach. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the viscous fingering phenomenon of two immiscible fluids in a channel is studied by applying the lattice Boltzmann method (LBM). The fundamental physical mechanisms of a finger formation or the interface evolution between immiscible fluids are described in terms of the relative importance of viscous forces, surface tension, and gravity, which are quantifiable via the dimensionless quantities, namely, capillary number, Bond number and viscosity ratio between displaced fluid and displacing fluid. In addition, the effect of wettability on flow behaviour of fluids is investigated for the cases with and without consideration of gravity, respectively. The numerical results provide a good understanding of the mechanisms of viscous fingering phenomenon from a mesoscopic point of view and confirm that the LBM can be viewed as a promising tool for investigating fluid behaviour and other immiscible displacement problems. [Copyright &y& Elsevier]

Abstract: This paper presents a model, using a phase-field method, that is able to simulate the motion of a solid sphere impacting on a liquid surface, including the effects of capillary and hydrodynamic forces. The basic phenomena that were the subject of our research effort are the small scale mechanism such as the wetting property of the solid surface which control the large scale phenomena of the interaction. The coupled problem during the impact will be formulated by the inclusion of the surface energies of the solid surface in the formulation, which gives a reliable prediction of the motion of solid objects in/on/out of a liquid surface and the hydrodynamic behaviours at small scales when the inertia of fluid is less important than its surface tension. Numerical results at different surface wettabilities and impact conditions will be presented and compared with the experiments of Duez el al. [C. Duez, C. Ybert, C. Clanet, L. Bocquet, Nat. Phys. 3 (2007) 180–183] and Lee and Kim [D. Lee, H. Kim, Langmuir 24 (1) (2008) 142]. [Copyright &y& Elsevier]

Abstract: A Monte Carlo approach based on energy potential including interface and volume energies is implemented, for the first time, in the framework of Eulerian interface tracking methods in order to deal with capillary driven two-phase flows. As a first step, the Monte Carlo approach is validated on the 2D Laplace’s law showing a first order convergence in space. A better accuracy is obtained compared to the standard Continuum Surface Force and Front Tracking approaches. As a second step, the simulation of the pressure field resulting from the action of the surface tension on complex static interface geometries is considered. These geometries correspond to the early times of the two-particle coalescence process. The two peaks of pressure within the contact zone are shown to be well estimated by the Monte Carlo method even when a very small interface curvature is involved. Indeed, the small scale modeling brought by the Monte Carlo methodology, which accounts for the interface in a Lagrangian manner, provides a description of the surface tension effects at a scale smaller than the Eulerian space scale. This work is a first step in coupling stochastic and deterministic models for the simulation of multiphase flows. [Copyright &y& Elsevier]

Abstract: The propagation of a steady saturation front in a double-layer porous material, situated between impenetrable walls, is investigated. The closed system of equations and boundary conditions are written on the assumption that the displacing and displaced phases, the viscosities of which differ considerably, are connected, and that the capillary pressure on the interface is constant. The features of the behaviour of the interface in the neighbourhood of the boundary of the layers are investigated in the case when the layer thicknesses differ considerably. When the permeabilities of the layers differ considerably, asymptotic expressions are obtained for the pressure and shape of the interface, and a comparison is made with the results of a numerical solution of the complete problem and with the known asymptotic relations obtained when using a simplified boundary condition at the interface. [Copyright &y& Elsevier]

Abstract: Based on discrete element simulations and micromechanical calculations, this paper presents studies on the shear strength properties of unsaturated granular materials with capillary effects. Capillary forces are described on the local scale, depending on the water content, and are superimposed on the standard dry particle interaction that is currently described through an elastic–plastic relation. Simulations of triaxial compression tests at several water-content levels in the pendular regime are used to investigate the macroscopic consequences of this local description. The two methods are in rather good agreement, both reproducing the dependency of shear strength on water content, as classically observed in laboratory experiments. For the water-content levels considered, a nonlinear evolution of the cohesion with the water content is obtained, resulting in shear-strength saturation with increasing water content. Moreover, the computations allow a capillary stress tensor to be exhibited from capillary forces, directly related to the cohesion of the material. Finally, emphasising this capillary stress contribution, the generalised effective stress concept is reviewed, with a conclusion on the limitations of the classical macroscopic description of water effects in unsaturated granular materials. [Copyright &y& Elsevier]

Abstract: In this work a vortex method is used to simulate an incompressible two-dimensional transitional flow over a backward-facing step. The simulations are validated for two different Reynolds numbers comparing to previous studies. Then, two different control strategies are implemented to modify the shedding, the recirculation zone behind the step and the transport in the channel. The first technique consists in using a pulsing inlet velocity and the second one is based on local oscillating jets implemented on the step vertical wall. The influence of these controls on several characteristic functionals related to the flow is carefully investigated. Both, open-loop and closed-loop active control approaches are performed in order to choose the most efficient control methods. [Copyright &y& Elsevier]

A matched asymptotic expansion is used to give a formal derivation of a number of systems of model equations for the evolution of interfacial waves subject to capillarity. For one of these systems, approximate solitary waves are found numerically, and the solutions are compared to the Benjamin equation which arises in the special case of one-way propagation. [Copyright &y& Elsevier]

A method of constructing the shape of the surface of a drop, hanging from a horizontal plane under the action of surface-tension forces, or lying on it or pressed between parallel planes, is proposed. [Copyright &y& Elsevier]

• Van der Waals p -system in the viscosity capillarity version is discussed. • Auxiliary equation mapping algorithm is implemented. • Painleve test is used to check integrability of model. • Some new solitary wave solutions are obtained successfully. This work proposes two well known schemes, painleve analysis test and auxiliary equation mapping (AEM) algorithm to find new solitary wave solutions for van der Waals p -system (VDW) in the viscosity capillarity version. For the clarity of physical features, new solitary wave solutions like periodic, kink and anti kink type, doubly periodic, trigonometric, singular, rational, combined soliton like solutions and hyperbolic solutions, etc. are articulated coupled with graphically patterns 2D, 3D and density plots to visualize the dynamics of our model. This study reveals that the methods used are simple, reliable, unambiguous and concise as compared to many other techniques for solving nonlinear partial differential equations (NLPDE). A new direct way to solve NLPDEs is provided using this approach. The method allows one to obtain new accurate solutions of the solitary wave that cannot be obtained using other methodologies, and it can be implemented on a computer using computer algebraic systems such as Mathematica or Maple. [ABSTRACT FROM AUTHOR]

• Capillary driven multiphase flow simulations do not converge with mesh refinement. • A semi-analytical correction function is defined using Washburn's equation. • A simple static contact angle correction can be used to correct the flow dynamics. • 3D simulations of two microfluidic devices show mesh-independency using the method. Precise modeling of contact angle is ubiquitous in capillary driven multiphase flow simulations. From a simple 2D rectangular capillary benchmark, we demonstrate and discuss the dependence of capillary dynamics on the mesh size with respect to Washburn's equation. Mesh-dependency is dominated by an underestimation of viscous losses for coarser meshes and transits to ever increasing stress-related errors due the Navier–Stokes equations breaking down in the vicinity of moving contact lines subjected to several known boundary conditions. Furthermore, computational limits generally impose mesh sizes for which none of the errors are negligible. We show that for Washburn-like flows, a simple modification of the static contact angle value is adequate to correct the dynamics of the flow. This semi-analytic correction has the advantage of requiring no modification of the source code or implementation of new boundary conditions, and thus can be easily used with any codes whether commercial or not. Simulations of a self-coalescence module and a capillary pump are presented as 3D verification test cases of the method. [ABSTRACT FROM AUTHOR]

Presents a humorous look at Brownian motion, motion without order, questioning its presence in physics textbooks. Examples of Brownian motion; Directions on how to perform an experiment involving Brownian motion.

We investigate theoretically the effects of capillarity and gravity on interfacial Marangoni waves (M-waves). Previous studies which neglected these effects have shown the decay rate of M-waves to vary monotonically. In this work, we disprove it by deriving a new dispersion relation (accounting for these effects) for the M-waves, and show that their decay rate passes through a minimum, rather than varying monotonically. This result, obtained numerically elsewhere, was explained using a hypothetical directional packaging process. Our explanation here is consistent with the bigger picture, which includes both capillary-gravity waves (CG-waves) and M-waves, which coexist at the contaminated interface of two fluids. It is known that the CG-waves undergo maximum dissipation at a critical value of interfacial elasticity, which provides the restoring force for the M-waves. Here, we complete the story; we show that the M-waves undergo minimum dissipation at a critical value of capillarity/gravity, which provide the restoring forces for the CG-waves. Previously, it has been hypothesized that the maximum decay rate for CG-waves is caused due to their resonance with M-waves. Here, we show this hypothesis to be true for a temporally-damped wave system, and that the resonance (in addition to causing the maximum decay rate for CG-waves) also causes the minimum decay rate for M-waves. [ABSTRACT FROM AUTHOR]

Cellulose-based foams are available commercially in a dry pre-compressed state, but can swell upon infiltration by a suitable liquid. A series of experiments reveal that pre-compressed foams can swell in one direction by an order of magnitude when infiltrated by water or glycerol; in contrast, no swelling accompanies infiltration by ethanol. The kinetics (and underlying mechanisms) of infiltration and of swelling are quantified by a series of critical experiments on both pre-compressed foam and pre-expanded foam, using water, glycerol and ethanol. Infiltration is driven by capillarity, cell wall diffusion and by opening of capillaries during swelling of the foam. Ethanol-infiltration of pre-expanded foam or of pre-compressed foam occurs by a combination of capillary action and diffusion without swelling of the foam. Water induces swelling of the pre-compressed foam on a time scale of 1 s, whereas glycerol swells the foam progressively over 105 s, after an initial incubation period of 103 s. When the foam is in the pre-expanded state, water and glycerol seep horizontally into the foam by capillary action; in contrast, water-rise and glycerol-rise in the vertical direction is initially by capillary action and then, once the Jurin height has been attained, diffusion leads to a much slower rate of seepage. Confirmation of the existence of a Jurin height for the vertical rise of water into pre-compressed foam or pre-expanded foam is obtained by X-ray computer tomography. Infiltration into pre-compressed foam by water or by glycerol involves the propagation of a swelling front, with liquid feeding first by capillary flow and then by diffusion within the cell walls. An understanding of liquid infiltration and the resultant swelling of foams is the first step in the design of actuating multi-scale lattices made from pre-compressed foam. [ABSTRACT FROM AUTHOR]

The article discusses a method devised by researchers at the University of Rochester, New York, which is published in the June 2, 2009 issue of “Applied Physics Letters,” to make a liquid at room- temperature flow against gravity. The team used a high-intensity laser with tiny channels etched in a metal plate. The plate was held vertically and methanol was pulled up the channels by evaporation and capillary action in a process called passive transport.

The article discusses corona splashing. The author states that when a drop of a liquid hits a surface, it can either spread, splash or rebound. With corona splashing, the upward component in the surface tension at the neck causes the leading edge of the radially spreading liquid film to bend upwards and give rise to the formation of a "corona", or crown. Corona splashing is found in milk, water, alcohols, and some paints.

The article discusses concrete moisture problems and how to address these. It states that 6-to-8-inch layer of crushed rock or gravel can stop the water's capillary rise, but the capillary break lets water convert to vapor. The author says that the worst moisture problems he has experienced have been in the desert states.

Reveals the role and non-role of capillarity in plants. Reasons why the radius of the xylem channels cannot play a role in the rise of sap; Condition that creates a tension or negative pressure within the water in the cell walls; Mechanism of transpiration pull; Features of angiosperm xylem; Place where the xylem might appear to be particularly vulnerable to damage.

The article offers information on gradient capillary high performance liquid chromatography (HPLC). HPLC provides the capability to conduct high throughput analysis with separation efficiencies. The important goal in drug discovery and development is to maximize the speed and resolution of HPLC. The HPLC systems must be able to provide precise rapid gradients with minimal delay volumes, high separation efficiencies and rapid re-equilibration to the starting conditions to maximize the speed and resolution.

This article focuses on findings of studies which showed that water's surface tension holds sandcastles together.

Focuses on scientific experiments that demonstrate the concept of surface tension. Ways by which surface tension explains the reason why the glass disk stick to the bottom of the empty glass; Scientific explanation behind surface tension.

This article informs about protective clothing. MicroMAX NS is the newest member of the protective clothing family from Lakeland Industries Inc. This line of microporous, general-purpose protective clothing can be used in any non-hazardous environment where dirt, grime, splashes, and spills are present.

Discusses how sponges hold water. Information on capillarity.