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In this paper, we are concerned with the large time behavior of the three-dimensional full compressible Navier-Stokes-Korteweg equations, which is used to model compressible viscous and heat-conductive fluids with internal capillarity, i.e., the liquid-vapor phase mixtures endowed with a variable internal capillarity. First, we construct the planar rarefaction wave to the three-dimensional full compressible Navier-Stokes-Korteweg equations, which can be derived by the fact that the rarefaction wave is nonlinearly stable to the one-dimensional full compressible Navier-Stokes-Korteweg equations. Then it is shown that the planar rarefaction wave is asymptotically stable provided that the initial data are a suitably small perturbation of the planar rarefaction wave and the strength of the rarefaction wave is small. The proof is based on the delicate energy method. [ABSTRACT FROM AUTHOR]

Dual-porosity structures of fine-grained soils can noticeably affect their ability to retain water. This work jointly employs axis translation technique, filter paper method, and vapor equilibrium technique to study the soil–water retention curve (SWRC) over a wide suction range of Nanyang expansive soil characterized by double porosity. Mercury intrusion porosimetry tests are carried out to investigate the correlations between the aforementioned water-retention response and underlying pore structure characteristics. The test data show that dual-porosity distribution leads to bimodal SWRC. The change in void ratio mainly affects the median size of the inter-aggregate pores and consequently the portion of SWRC at low suction range. Based on these experimental observations, this work presents an SWRC equation for fine-grained soils with dual-porosity structures. Attracting water through capillary and adsorptive processes is explicitly distinguished. The capillary water is described by a relation that includes the characteristics of both inter- and intra-aggregate pore size distributions as parameters for representing bimodal characteristics. The adsorbed water is modeled by a relation that considers capillary condensation within intra-aggregate pores and allows for the decoupling between adsorptive water-retention mechanism and void ratio change. The latter feature is the foundation for the model to include the void ratio effect on SWRC in a way consistent with how it affects the pore structures of soils. By simulating test data in this work and in the literature, the proposed model is shown to be capable of representing the water-retention behavior of fine-grained soils with dual-porosity structures under different void ratios. To include the aforementioned key factors that influence the SWRC of fine-grained soils, seven parameters are required in the proposed model. This feature can reduce the practical applicability of the model. Future directions to enhance this aspect are discussed. [ABSTRACT FROM AUTHOR]

In Brazil, the interstate road passenger transport is considered a public service. It is organized by a public agency, the National Land Transport Agency ("ANTT"), and operated by private agents which manage a wide and combined set of people and cargo's displacements around the national territory. The interstate road passenger transport is a service with high capillarity, as it connects urban centers of different sizes and uses the road network to carry people and cargo's flows. Interstate transport reflects uneven development, and it shows a diversity of spatial interactions that take place all over the Brazilian territory. Therefore, this article analyzes the highways of the municipality of Goiânia/GO, its uneven development, and interstate road transport of passengers. The text is organized in three parts which are theoretically based on bibliographic research. The results were based on population data provided by national public institutions and information about the interstate lines were obtained on the ANTT website in order to support the main article debate. [ABSTRACT FROM AUTHOR]

The multi-phase solver interFoam within the open-source CFD software OpenFOAM is newly applied to rare experiments conducted beginning over 10 years ago aboard the International Space Station (ISS). The fluid physics of interest concern large length scale passive capillary flows in a microgravity environment driven largely by surface tension, wetting conditions, and container or conduit geometry. Such flows are critical to orbiting and coast spacecraft liquid fuels, propellants, cryogens, thermal fluids, and aqueous streams for water management, recycling, and life support. The value of the simulations is assessed via quantitative comparisons to the ISS Capillary Flow Experiments (CFE) for a series of centimetric handheld test cells. Three representative flows are simulated as functions of geometric complexity: 1) bubble coalescence, 2) ullage migration, and 3) draining flow. The experimental data is newly digitized for the bench-marking effort. The favorable agreement between the simulations and experiments adds confidence for advanced applications of the native interFoam multi-phase solver of the OpenFOAM suite, where experimental data is scarce. [ABSTRACT FROM AUTHOR]

Capillary trapping is considered as one of the safest geologic CO2 storage mechanisms due to its hydrodynamic stability. However, the thermodynamic stability of capillary trapping was questioned by our recent work (Xu in Geophys Res Lett 46(23):13804–13813, 2019). Gravity induces the top bubbles to grow at expense of bottom bubbles through the diffusion of dissolved gas components, that finally may form a gas cap and posing a risk of leakage, even in absence of convection. Here, we improve the gravity-induced ripening model introduced earlier and conduct theoretical and numerical analysis. Four regimes of bubble ripening are identified according to the modified Bond number and initial gas saturation, resulting in different scaling between the equilibrium time and the length scale. Vertical heterogeneity is also shown to have a great impact on the ripening process. When the permeability gradient is downward, the capillary pressure gradient competes with the gravitational gradient and results in a complex gas redistribution behavior. Capillarity dominates in a short time, while gravitational potential determines the global saturation profile in long term. This work provides a new physical perspective in evaluating CO2 sequestration security and has a potential application in other porous systems that gas generated and evolve under strong external fields. [ABSTRACT FROM AUTHOR]

The conservation of stones containing swelling clay minerals such as montmorillonites is a challenging task. In this context, swelling inhibitors (DAA) were tested and a treatment based on consolidation with TEOS (ethyl silicate) was carried out on a sandstone containing swelling clay minerals: the Itararé Sandstone (commercial name). In this laboratory experiment, the inhibition of swelling, pore size and distribution, capillarity, colorimetric alteration, durability of treatments against the action of water, effectiveness of consolidation, and penetration depth were evaluated. Swelling inhibitors were effective in inhibiting the clay minerals from swelling. The consolidant, despite its effectiveness, altered the pore size and distribution and water absorption significantly, forming a very cracked gel, darkening the stone, reducing resistance to the action of water and presenting small penetration depth. When swelling inhibitors were applied before the consolidant, swelling inhibition also occurred, the porosity was less altered, the consolidant was less cracked, there was less chromatic modification and the sample became more resistant to the action of water. Therefore, this treatment proved to be more effective with fewer changes to the physical characteristics of the stone than the sole application of the consolidant. [ABSTRACT FROM AUTHOR]

Foamed concrete has superior rheological and thermal insulation properties along with a low density and high strength/weight ratio. Also, foamed concrete has reduced manufacturing and transportation costs compared to conventional concrete and can be utilized in structural elements. Foamed concrete significantly lowers the self-weight of the superstructure and contributes large energy savings. This review mainly focuses on the ingredients and techniques required for the production of foam concrete, mix design techniques, and the physical, functional, and mechanical properties. The key motive for this systematic quantitative literature survey was to identify research gaps in existing literature and also to provide extensive insights regarding suitable applications of cellular concrete. [ABSTRACT FROM AUTHOR]

This paper studies modifications made to the Bosanquet equation in order to fit the experimental observations of the liquid filling process in circular tubes that occurs by capillary force. It is reported that there is a significant difference between experimental observations and the results predicted by the Bosanquet equation; hence, it is reasonable to investigate these differences intensively. Here, we modified the Bosanquet equation such that it could consider more factors that contribute to the filling process. First, we introduced the air flowing out of the tube as the liquid inflow. Next, we considered the increase in hydraulic resistance due to the surface roughness of the inner tube. Finally, we further considered the advancing contact angle, which varies during the filling process. When these three factors were included, the modified Bosanquet equation was well correlated with the experimental results, and the R square—which indicates the fitting quality between the simulation and the experiment—significantly increased to above 0.99. [ABSTRACT FROM AUTHOR]

The constitutive relationship between suction and degree of saturation is of great significance for estimating the shear strength and deformation behavior of unsaturated soils. A unimodal/bimodal soil-water retention curve (SWRC) is proposed considering the effects of various pore structures and the effects of void ratio on capillarity and adsorption. The different mechanisms of water retention through capillarity and adsorption are explicitly distinguished in the proposed model. The relationship between the capillary degree of saturation and suction is described as a specific function related to the characteristics of pore-size distribution, while the adsorptive degree of saturation is modeled considering the effect of capillary condensation explicitly. Subsequently, the decoupling formula of capillary and adsorptive saturation is further put forward. The formula lays a foundation for the model to account for the dependence of capillary part of SWRC on void ratio, which is consistent with the results from micro-scale tests. Eventually, an approach to estimate the shear strength of unsaturated soils with different initial void ratios has been proposed based on the improved SWRC model. The model is verified using data from water retention and direct shear tests reported for various types of soils in the literature.

We investigate, under a volume constraint and among sets contained in a Euclidean half-space, the minimization problem of an energy functional given by the sum of a capillarity perimeter, a nonlocal interaction term and a gravitational potential energy. The capillarity perimeter assigns a constant weight to the portion of the boundary touching the boundary of the half-space. The nonlocal term is represented by a double integral of a positive kernel g , while the gravitational term is represented by the integral of a positive potential G. We first establish existence of volume-constrained minimizers in the small mass regime, together with several qualitative properties of minimizers. The existence result holds for rather general choices of kernels in the nonlocal interaction term, including attractive–repulsive ones. When the nonlocal kernel g (x) = 1 / | x | β with β ∈ (0 , 2 ] , we also obtain nonexistence of volume constrained minimizers in the large mass regime. Finally, we prove a generalized existence result of minimizers holding for all masses and general nonlocal interaction terms, meaning that the infimum of the problem is realized by a finite disjoint union of sets thought located at "infinite distance" one from the other. These results stem from an application of quantitative isoperimetric inequalities for the capillarity problem in a half-space. [ABSTRACT FROM AUTHOR]

The Cu-Ni system is a typical dissolutive system due to its mutual dissolution across a wide range of temperatures and compositions. We characterized the effects of Ni dissolution on the wetting behavior of liquid Cu by combining high-temperature wetting experiments, in-situ observation of spreading and solidification, microstructure analysis of the quenched droplets, and computational fluid dynamic (CFD) simulations. In the very early moment, at 1100 °C, when the Cu droplet is brought in contact with the Ni substrate, it oscillates due to capillarity and is dampened by inertial effects, while the significant Ni dissolution at 1150 °C largely reduced the initial oscillations. Later, a peculiar spreading behavior is observed and we propose to describe it through a 4-step mechanism: pinning of the contact line by a newly formed solid solution layer at the interface acting as a physical barrier, driving of liquid towards the solidified edge due to a Ni-concentration induced Marangoni flow, forming of a precursor film ahead of the solidified edge caused by the strong Cu-Ni interactions and Marangoni flow, and finally depinning due to overflow as a result of liquid accumulation at the solidified edge. The formation of a solid solution layer is confirmed by in-situ observation and quenching. The Ni-concentration induced Marangoni flow is characterized experimentally and further investigated by CFD simulations. The proposed step flow mechanism can be potentially relevant to other dissolutive wetting systems (e.g. Bi/Sn, Ag/Cu and Cu/Fe systems), which are crucial for high-temperature processing techniques. [Display omitted] [ABSTRACT FROM AUTHOR]

• The cementation lithofacies of tight sandstone was classified as: (i) calcite cementation lithofacies (CAL) and (ii) clay cementation lithofacies (CLL). • During CO 2 flooding in CAL, small pores transform into large pores. • During CO 2 flooding in CLL, both large and small pores increase simultaneously. • The frontal movement of CO 2 migration is unstable in CAL samples, due to the positive feedback loop. • The frontal movement of CO 2 migration is relatively stable in CLL samples, due to low penetration rate of CO 2 -water–rock reactions. The injection of CO 2 into tight formations provides a dual benefit: the improvement of the reservoir recovery and the facilitation of the CO 2 sequestration. However, uncertainty remains regarding the pore changes and the CO 2 characteristics owing to the complex cementation lithofacies. Here, this study combines low-field nuclear magnetic resolution and inductively coupled plasma emission spectrometer to investigate the changes in pore structure and migration dynamic characteristics during CO 2 flooding. The experiments were performed in the Chang 7 tight sandstone layer of the Triassic Yanchang Formation from the Ordos Basin in China. Results indicate that the lithofacies of the tight formation can be classified as (i) calcite cementation lithofacies and clay cementation lithofacies. During calcite cementation lithofacies in CO 2 flooding, the mineral dissolution rate accelerates and the pore size increases by 26.25%. The pore enhancement and front velocity form a positive feedback loop, leading to an unstable CO 2 migration front. Dissolution and mineral trapping turn to be significant as the flooding progresses in the tight sandstone with abound calcite, making it an advantageous site for CO 2 geosequestration. During CO 2 flooding in clay cementation lithofacies, total pores increase by 11.58%. The propagation of the reaction front is retarded by the low pore increment and significant capillarity, leading to a stable front movement. Residual trapping becomes the most significant contributor to overall CO 2 trapping in the tight sandstone with abound clay. The results of this study supplement the difference in CO 2 migration characteristics of different lithofacies, and can provide new insights for the oil recovery improvement and CO 2 geosequestration in tight formation. [ABSTRACT FROM AUTHOR]

In this short note we prove that the Winterbottom shape (Winterbottom in Acta Metallurgica 15:303-310, 1967) is a volume-constraint minimizer of the corresponding anisotropic capillary functional. [ABSTRACT FROM AUTHOR]

• A sphere-cylinder binary pore is proposed to describe the unfrozen water hysteresis of soil–water system. • The upper/lower boundaries of freezing/thawing curve with natural pores are those with idealized cylindrical/spherical pores. • The maximum hysteresis is in the second stage, followed by the first, third, and fourth stages. The soil freezing-thawing characteristic curve (FTCC) can reflect the physical and mechanical properties of soil–water system during freezing-thawing (FT) process, which is of guiding significance to the study of soil moisture, heat and matter transport in cold regions. In this study, firstly, according to the evolution law of freezing-thawing hysteresis with freezing-thawing process, revealing the hysteresis mechanisms at different stages based on ice-water transformation theory. The freezing-thawing hysteresis can be divided into four stages as temperature decreasing. The hysteresis of the first three stages are due to nucleation and electrolyte effects, capillarity and pore clogging effects, structural damage effect, respectively; and the last stage is extremely weak and can be ignored. Secondly, evaluating freezing-thawing curves of soil–water system with three pore structures (cylindrical, spherical, and sphere-cylinder binary pore) based on the thermodynamic theory, quantitatively. The upper and lower boundaries of the freezing/thawing characteristic curve with natural pores are those with idealized cylindrical and spherical pores, respectively. Finally, the evaluation index (i.e., hysteresis degree) was introduced to quantitatively describe the variation of unfrozen water hysteresis degree with freezing-thawing process. The relationship between the unfrozen water hysteresis degree and temperature can be divided into four stages. The maximum hysteresis degree was found in the second stage, indicating that hysteresis was most significant in the second stage, followed by the first, third, and fourth stages. Our results provide theoretical support for studying hydrothermal characteristics and water, heat, and solute transport of geotechnical materials in seasonally frozen regions. [ABSTRACT FROM AUTHOR]

• Inspiration on the heterogeneous nature of water adsorption in bentonites. • Noval (continuum) SWRC model considering adsorption and capillarity. • New model contains only 5 parameters, with high efficiency in parameter estimation. • A graphical method was suggested to estimate maximum adsorption capacity. Understanding soil–water retention behavior is a longstanding topic. Water retained in soils can be decomposed into adsorptive and capillary components, controlled by different physicochemical mechanisms. The capillary water retention was frequently discussed in literatures, but the adsorption role was rarely considered, especially for high active clays (e.g., bentonite). In this study, two novel equations for quantifying adsorptive and capillary water retentions are proposed, generating a twofold model to continuously simulate soil–water retention behavior of bentonites. Only 5 parameters, i.e., the maximum adsorption capacity, characteristic adsorptive and capillary suctions, and uniformities of adsorptive and capillary pores, are defined with clear physical meanings. A graphical method was suggested to firstly determine the maximum adsorption capacity, and the remaining parameters are efficiently estimated by non-linear curve fitting. The water retention data for various bentonites, representing a variety of hydration conditions, initial compactness, montmorillonite content and suction range, are used to assess the model performance. The predictions agree well with the measured total, adsorptive and capillary water contents of a Wyoming bentonite, and the fitting curves also match well with test data for other bentonites over the full suction range. Adsorption parameters are distributed within a narrow range, while the characteristic capillary suction is also distributed within a limited range under constant volume condition. The proposed model allows reasonable predictions about the capillary onset and the transition from adsorption to capillarity, revealing obvious superiority by comparison with other hybrid models. This work offers a new pathway to quantitively assess the soil–water retention curve of high active clays. [ABSTRACT FROM AUTHOR]

The current study adopts a micromechanical approach to explore the nature of stress transmission in wet granular materials. First, we derive the discrete form of the capillary stress tensor obtained from homogenization to show the virial nature of capillarity through the application of point-wise capillary forces in Discrete Element Modeling (DEM). Furthermore, the non-spherical character of the capillary stress tensor is highlighted through a series of DEM triaxial simulations. Contrary to common thinking, the capillary stress tensor has indeed both mean and deviatoric components due to the underlying micromechanical aspects. Relevant key dimensionless parameters are identified to evaluate the relative magnitude of the capillary stress to the externally applied and contact (intergranular) stresses, thus determining the specific conditions under which the contribution of the deviatoric part becomes considerable. In addition, a DEM simulation of a simple shear test is performed to confirm the anisotropy (non-sphericity) of capillary stress tensor. Finally, the effective nature of the contact stress in the sense of Terzaghi for the constitutive behavior of wet granular materials is investigated via a DEM stress probing analysis. Results suggest that a single contact stress variable – germane to an effective stress – cannot relate to strain for the constitutive law in triphasic condition. • Capillary stress is virial through point-wise intergranular capillary forces in DEM. • The non-spherical nature of the capillary stress tensor is formally demonstrated. • A p -constant shear test reveals the existence of purely deviatoric capillary stress. • Capillary stress is more deviatoric at higher suctions and lower confining stresses. • The contact stress cannot play the role of an effective stress for wet materials. [ABSTRACT FROM AUTHOR]

Wood materials incorporating new properties are of great interest, especially for advanced applications such as sustainable optics and photonics. In this work we describe a wood functionalization approach, comprising the incorporation of artificial chemiluminescent systems (phenyl oxalate ester‑hydrogen peroxide-fluorophore, and luminol-ferricyanide), resulting in light-emitting wood. By a detailed characterisation of the light emission features we point out the complex interaction between wood scaffold and chemiluminescent systems, especially the quenching effect of wood extractives (for the TCPO-H 2 O 2 -fluorophore system) and lignin (for the luminol-ferricyanide system). Moreover, we take advantage of the intrinsic anisotropic porosity and capillarity of wood tissue to study the chemiluminescent front propagation. Our results may inspire the development of novel light-emitting wood materials for a variety of applications, from fundamental studies of water uptake in wood to sensors and even design elements. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, the hydrodynamic performance of a bottom-seated type oscillating water column (OWC) device is investigated by numerical and experimental methods. A coupled SPH (Smoothed Particle Hydrodynamics) - FDM (Finite Difference Method) is proposed to simulate the interaction between waves and the OWC device. The current SPH-FDM model improves grid encryption method, and expand the single-phase SPH-FDM to multiphase SPH-FDM. The results from SPH-FDM align closely with those from the published experimental measurements. Following the successful validations, SPH-FDM and experiment are employed for a series of simulations to investigate the performance of the OWC device. Compared to experimental method, SPH-FDM can obtain global flow field information and avoid the influence of free surface identification and capillarity on vortex determination. In addition, SPH-FDM can naturally captures free surfaces, so it supports further studies on the non-uniformity of water surface in the chamber of OWC which cannot be studied by PIV or pneumatic model. • An improved SPH - FDM is proposed to simulate the interaction between waves and an OWC device. • Simulations and experiments indicate that water levels near side walls of chamber differ from those in the middle of chamber. • Compared to experiments, SPH-FDM can get global information and avoid interference of free surface and capillarity. [ABSTRACT FROM AUTHOR]

A detailed statistical description of the evolution of supersaturated-by-gas solution at degassing has been presented on the basis of finding the time-dependent distribution in radii of overcritical gas bubbles. The influence of solution viscosity and capillarity via internal pressure in the bubbles on this distribution has been considered until the moment when the gas supersaturation drops due to depletion and stops nucleation of new overcritical gas bubbles. This study is based on our previous results for the nonstationary growth rates of overcritical bubbles depending on gas supersaturation, diffusivity and solubility in solution, solution viscosity, and surface tension on bubble surface. Other important factors are linked with the initial rate of homogeneous gas bubble nucleation and coupling between diffusivity and viscosity in the solution. Here, we numerically studied how all these factors affect the time-dependent distribution function of overcritical bubbles in their radii, maximal and mean bubble radii, and the time-dependent swelling ratio of a supersaturated-by-gas solution in a wide range of solution viscosities.

In this paper, we consider a compressible fluid model of the Korteweg type on general domains in the N-dimensional Euclidean space for N≥2. The Korteweg-type model is employed to describe fluid capillarity effects or liquid–vapor two-phase flows with phase transition as a diffuse interface model. In the Korteweg-type model, the stress tensor is given by the sum of the standard viscous stress tensor and the so-called Korteweg stress tensor, including higher order derivatives of the fluid density. The local existence of strong solutions is proved in an Lp-in-time and Lq-in-space setting, p∈(1,∞) and q∈(N,∞), with additional regularity of the initial density on the basis of maximal regularity for the linearized system.

The interaction of nitinol melt with Al 2 O 3 , ZrO 2 , BeO and Y 2 O 3 oxides used as crucible materials has been studied. Capillary interaction has been monitored directly using the method of sessile drop with video and thermal imaging in 10−3torr vacuum at 1350 °C. Nitinol melt drops have been formed in a high-density graphite dispenseror directly on the substrate surface. The contact angleson the surface of polished oxides have been obtained. The contact angles established within 30 s increase in the sequence Al 2 O 3 , ZrO 2 , BeO and Y 2 O 3 from 30° to 70°. The corrosion resistance of the oxides has been studied for cross-sections using scanning electron microscopy with energy dispersion analysis. The phase composition at the ceramic/melt boundary has been studied using transmission electron microscopy. Thermodynamic analysis of melt chemical interaction with oxides has been conducted within equilibrium concentration calculation. • The interaction of Nitinol melt with Al 2 O 3 , ZrO 2 , BeO and Y 2 O 3 oxides crucible. • The contact angles increase in the sequence Al 2 O 3 , ZrO 2 , BeO and Y 2 O 3. • The order of change in the contact angles was Y 2 O 3 70о; BeO 62о;ZrO 2 53о; Al 2 O 3 30о. • This order is inverse to that of reaction constants of metal reduction from oxides by titanium. • The low contact angles of nitinol on Al 2 O 3 , BeO and ZrO 2 (Y) allow this melt to be recommended as solder at above 1310 °C. [ABSTRACT FROM AUTHOR]

Rapid rehydration is a critical factor to consider when evaluating the quality of instant noodles. In this study, freeze-dried rice noodles (FDRNs) were prepared by incorporating varying mass ratios (0.5–2.0 g/100g) of raising agents (RA). The influence of the RA on the physicochemical properties, water migration dynamics, and rehydration process of the FDRNs was investigated in this paper. The DMA results indicated that adding RA altered mechanical modulus and thermal temperatures in FDRNs. The morphological analysis of SEM revealed that the porous structure of FDRNs was enhanced when the RA content was 1.0 g/100g. After soaking in hot water (65, 75, and 85 °C), rehydration curves and the Peleg model could distinguish the rehydration process of FDRNs into three stages, including external wetting, internal capillarity, and core hygroscopicity. The textural properties of FDRNs were also affected by adding RA. The LF-NMR revealed an increased consumption time for the core hygroscopicity and promoted the formation of component-interacted water, suggesting that the RA added to FDRNs facilitated water migration within the core hygroscopicity stage and accelerated the rehydration rate thereafter. These data sets can provide a practical application of water-controlling strategies in producing high-quality instant rice noodles. • Adding RA altered mechanical modulus and thermal temperatures in FDRNs. • FDRNs rehydration including external wetting, internal capillarity, and core hygroscopicity. • RA assisted water migrate from free water to component-interacted bound water. • Adding RA to FDRNs facilitated water migration within core hygroscopicity stage. • Inappropriate uses of RA do not promote the rehydration process of FDRNs. [ABSTRACT FROM AUTHOR]

In this contribution, we derive a gas–liquid two-scale multi-fluid model with capillarity effects to enable a novel interface regularization approach for multi-fluid models. As this unified modelling is capable of switching from the interface representation of a separated to a disperse regime it lays a new way of modelling regime transitions as it occurs in atomization processes. Above a preset length threshold at large scale , a multi-fluid diffuse interface model resolves the dynamics of the interface while, at small-scale , a set of geometric variables is used to characterize the interface geometry. These variables result from a reduced-order modelling of the small-scale kinetic equation that describes a collection of liquid inclusions. The flow model can be viewed as a two-phase two-scale mixture, and the equations of motion are obtained thanks to the Hamilton's Stationary Action Principle, which requires to specify the kinetic and potential energies at play. We particularly focus on modelling the effects of capillarity on the mixture's energy by including dependencies on additional variables accounting for the interface's geometry at both scales. The regularization of the large-scale interface is then introduced as a local and dissipative process. The local curvature is limited via a relaxation towards a modified Laplace equilibrium such that an inter-scale mass transfer is triggered when the mean curvature is too high. We propose an original numerical method and assess the properties and potential of the modelling strategy on the relevant test-case of a two-dimensional liquid column in a compressible gas flow. [Display omitted] • Unified two-scale modelling of interfacial flows relying on geometrical variables. • Inter-scale coupling with a dissipative mass transfer coherent with capillary energy. • Local regularization of the large-scale interface through a mean curvature threshold. • Numerical strategy relying on an implicit–explicit specific relaxation scheme. • Simulation of a deformed liquid column assessing the capabilities of the modelling. [ABSTRACT FROM AUTHOR]

A cellulose-based matrix for monitoring milk freshness (MF) was produced from rice straw particles (RSPs) in a 0.125–0.150 mm that was bis-quaternized to attach bromocresol purple (BP) as a sensor. Under alkali conditions, the obstinate structure of the rice straw had opened, thereby improving the accessibility of the cellulose. Bis-quaternization created more adsorption sites for BP. The maximum adsorption capacity was 97.68 mg/g. The sensors were interwoven with cellulosic fibers to form the cellulose-based label with a relatively loose three-dimensional structure via hydrogen bonds. As the proportion of BP-BCRPs was increased from 10% to 40%, the air permeability of the label increased from 3.76 to 15.01 mm/s, which increased the response to the tested gases (10.12 s for 1 mL of acetic acid). The intelligent label exhibited excellent sensitivity at pH values of 3–9 with highly saturated color changes. During the storage period, the label color shifted from blue-purple to yellow as acidity was increased from 17.24 to 19.8 °T due to capillarity action, providing a timely warning to consumers. The prepared colorimetric porous intelligent cellulose-based label is suitable for monitoring of MF.

Realizing a balance between water supply and the evaporation of photothermal evaporators is a valuable means to enhance the solar–thermal evaporation rate, but practical obstacles remain. The interfacial mechanics of a Janus evaporator with an interpenetrating structure are proposed to achieve a dramatic improvement in the solar–thermal evaporation rate. The Janus evaporator is composed of a membrane material of Cu1.96S grown in situ on a foamed copper skeleton (CF@Cu1.96S) and a graphene oxide/sodium alginate aerogel (GA), through an interfacial freeze-drying shape technology. In this unique architecture, the superhydrophilic GA can be stretched into the hydrophobic CF@Cu1.96S interior to build an interpenetrating network architecture (CF@Cu1.96S/GA), thereby adjusting the Laplace pressure and constraining capillarity. Due to the optimized water supply of interfacial mechanics, the CF@Cu1.96S/GA evaporator achieves an evaporation rate of 1.79 kg m−2 h−1 under 1 sun irradiation and exhibits superior salt resistance. This provides a rationale for the reasonable design of the structure of the solar–thermal evaporators. [ABSTRACT FROM AUTHOR]

Endowing supercapacitors with higher energy density is of great practical significance but remains extremely challenging. In this work, an innovative densified 3D printing enabled by a surface‐adaptive capillarity strategy is proposed for the first time. The printable ink formulated with pyrrole surface‐modified reduced graphene oxide renders the printed electrodes excellent surface tension regulability to the subsequent capillary densification, creating an intensely condensed electrode with well‐maintained structural integrity. Furthermore, simultaneous in situ nitrogen doping and hierarchical micro–meso porosity are readily realized upon post‐carbonization, encouraging enhanced capacitance and fast reaction dynamics. As a result, the printed symmetric supercapacitor delivers a double leap in areal and volumetric energy densities in both aqueous and organic electrolytes, a rarely achieved yet gravely desired attribute for 3D printed energy storage devices. [ABSTRACT FROM AUTHOR]

Pore-water pressure in soil is caused by three physically distinguishable sources: ambient (environmental) pressure, surface tension–induced capillary pressure, and the soil's electromagnetic potential–induced adsorptive pressure. The former two form the conventional concept of pore-water pressure, which is considered a constant within a soil-water-air representative elementary volume and can be directly measured by piezometer (under saturated and compressive states) or tensiometer (under unsaturated and tensile states). The third one can be called adsorption-induced pore-water pressure and is localized within a certain distance to the particle surface of soil or intercrystalline surface of swelling clay. The adsorption-induced pore-water pressure is always compressive and dictates the water phase transition in soil by altering water's freezing point, density, and viscosity, among other physical properties. A framework of quantifying the adsorption-induced pore-water distribution via the measured soil water isotherm is presented for any soil type under any given water content. It is demonstrated that the adsorption-induced pore-water pressure can be up to 1.6 GPa in the first few layers of hydration, but will diminish to zero at a distance equivalent to the gravimetric water content >1% for sandy soil and greater than a few percent for silty soil. In clayey soil, the adsorption-induced pore-water pressure can sustain tens of megapascals even at much farther distance, equivalent to ∼30% water content. In expansive clay, the adsorption-induced pore-water pressure inside the crystalline lamellae can exceed 800 MPa. The soil water density functions of a silty soil and a bentonite clay predicted by the proposed framework matched well with that measured independently from the conventional consolidation testing, validating the framework to determine the spatial distribution of the adsorption-induced pore-water pressure in soil. [ABSTRACT FROM AUTHOR]

Soil sorptive potential (SSP) has recently been conceptualized as the sum of four known electromagnetic potentials in soil: cation and surface hydration, van der Waals attraction, electrical attraction, and osmosis due to electrical double layer. The SSP is most pronounced near the soil particle or intracrystalline surface and rapidly decays with increasing distance therefrom, governing the highly spatially varying characteristics of many fundamental soil properties such as pore water pressure, soil water density (SWD), and soil water phase transition. A novel framework was developed to determine the functions of SSP and SWD, directly using the experimental soil water isotherm (SWI) data with the aid of closed-form SWI and SWD models. A wide spectrum of soil types was examined to validate the proposed framework. Results indicate that the SSP in these soils can vary up to six orders of magnitude within the first three layers of adsorbed water molecules, leading to abnormally high values in both water pressure (∼103 MPa) and SWD (1.26 g/cm3) at the soil–water interface. The predicted SWD curves are comparable to the existing experimental SWD measurements, and the controlling parameters for the SSP calibrated by the predicted SSP curves also show good agreement with the values reported in the literature, all confirming the validity of the proposed framework. It is concluded that soil sorptive potential and soil water density functions can be reliably determined from soil water isotherm data. [ABSTRACT FROM AUTHOR]

This study presents a simple route to fabricate shape imprinted microspheres and their application toward multiplex immunoassay. Specifically, a photocurable fluid (polyethylene glycol diacrylate, [PEGDA]) confined in a micromold results in drop formation due to mold swelling and capillarity upon addition of immiscible wetting fluid; during this formation, part of the photocurable fluid is entrapped at the swollen open end, thereby producing polymeric microspheres with controlled imprinted shapes on their surface upon photopolymerization. This approach is able to produce highly uniform microspheres with different imprinted shapes depending on mold geometry in a consistent manner; their size can also be tuned by varying mold dimensions. Furthermore, we impart amine‐reactive functional groups to the microsphere, which allows them to be functionalized efficiently. Lastly, we conjugate different capture antibodies on microspheres with different imprinted shapes, and these microspheres were demonstrated to be shape‐encoded suspension arrays for multiplex immunoassays. This technique provides high selectivity and a simple decoding method for biosensing applications. [ABSTRACT FROM AUTHOR]

This work presents and discusses a series of experiments focusing on the transport of floating particles, mimicking seeds and propagules, within an array of randomly arranged cylinders mimicking emergent vegetation stems. The focus is on the temporary capture process by which particles colliding with a cylinder are trapped by surface tension for finite but relatively long retention times, thus promoting a large mechanical dispersion. Video analysis of the particle paths within the array shows that the probability of particles being captured, either temporarily or permanently, as well as the mean retention time, vary with flow velocity while being weakly affected by stem density. On the contrary, stem density plays a significant role in determining the frequency of the temporary captures; in particular, the probability of having temporary, rather than permanent, captures increases with vegetation density. We also propose some relationships to predict the probability of having temporary capture events and their mean duration based on experimental results. Key Points: The probability that floating particles are captured by emerging stems is weakly dependent on stem densityTemporary captures increase with stem density at the expense of permanent captures due to the turbulence generated by vegetationMean retention time of captured particles is inversely related to the mean flow velocity within the canopy [ABSTRACT FROM AUTHOR]

The efficiency of three commercial hydrophobic coatings applied on two types of sandstones was subjected to the tests of water absorption by capillarity, water absorption by complete immersion, and frost resistance. Two days of the curing time of coatings on samples were chosen for the laboratory tests. The effects of the used coatings were different (ambiguous). Two coatings proved their effectiveness and thus, relevance of their use, but different coatings were effective on each type of sandstone. The coating F showed the best efficiency for the Hořice sandstone and coating A for the Malé Skalky sandstone. The third testing coating H was ineffective on both types of sandstone. The water absorption tests by capillarity showed a loss of the coating effectiveness over time. By completely immersing the samples in water, all three coatings lost their effectiveness and the hydrophobic effects disappeared. Applied protective coatings helped to preserve the frost resistance of the Hořice sandstone when looking at the uniaxial compressive strength after 25 freeze–thaw cycles, regardless of their fading hydrophobic effect. In addition, a penetration depth test for Hořice sandstone was performed. The impregnation depth reflects the effectiveness of the coatings and confirmed the results obtained by the water absorption tests by capillarity. The findings presented in the article are also useful in practice, as Hořice sandstone will be mined and frequently used in the future as well. [ABSTRACT FROM AUTHOR]

Soap films at equilibrium are modeled, rather than as surfaces, as regions of small total volume through the introduction of a capillarity problem with a homotopic spanning condition. This point of view introduces a length scale in the classical Plateau's problem, which is in turn recovered in the vanishing volume limit. This approximation of area minimizing hypersurfaces leads to an energy based selection principle for Plateau's problem, points at physical features of soap films that are unaccessible by simply looking at minimal surfaces, and opens several challenging questions. © 2022 Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Copyright of Law Studies Journal / Revista Novos Estudos Juridicos is the property of Novos Estudos Juridicos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In his seminal paper on the solution of the infiltration equation, Philip (1969), https://doi.org/10.1016/b978-1-4831-9936-8.50010-6 proposed a gravity time, tgrav, to estimate practical convergence time and the time domain validity of his infinite time series expansion, TSE, for describing the transient state. The parameter tgrav refers to a point in time where infiltration is dominated equally by capillarity and gravity as derived from the first two (dominant) terms of the TSE. Evidence suggests that applicability of the truncated two‐term equation of Philip has a time limit requiring higher‐order TSE terms to better describe the infiltration process for times exceeding that limit. Since the conceptual definition of tgrav is valid regardless of the infiltration model used, we opted to reformulate tgrav using the analytic implicit model proposed by Parlange et al. (1982), https://doi.org/10.1097/00010694-198206000-00001 valid for all times and related TSE. Our derived gravity times ensure a given accuracy of the approximations describing transient states, while also providing insight about the times needed to reach steady state. In addition to the roles of soil sorptivity (S) and the saturated (Ks) and initial (Ki) hydraulic conductivities, we explored the effects of a soil specific shape parameter β, involved in Parlange's model and related to the type of soil, on the behavior of tgrav. We show that the reformulated tgrav (notably tgrav=F(β)S2/Ks−Ki2, ${t}_{\text{grav}}=\,F(\beta){S}^{2}/{\left({K}_{s}-{K}_{i}\right)}^{2},$ where F(β) is a β‐dependent function) is about three times larger than the classical tgrav given by tgrav,Philip=S2/Ks−Ki2 $\,{t}_{\text{grav},\text{Philip}}={S}^{2}/{\left({K}_{s}-{K}_{i}\right)}^{2}$. The differences between the classical tgrav,Philip and the reformulated tgrav increase for fine‐textured soils, attributed to the time needed to attain steady‐state infiltration and thus i + nfiltration for inferring soil hydraulic properties. Results show that the proposed tgrav is a better indicator of time domain validity than tgrav,Philip. For the attainment of steady‐state infiltration, the reformulated tgrav is suitable for coarse‐textured soils. Still neither the reformulated tgrav nor the classical tgrav,Philip are suitable for fine‐textured soils for which tgrav is too conservative and tgrav,Philip too short. Using tgrav will improve predictions of the soil hydraulic parameters (particularly Ks) from infiltration data compared to tgrav,Philip. Key Points: A new formulation for infiltration characteristic time, tgrav, is providedThe reformulated tgrav seems to be a better criterion for convergence time of Philip's truncated infiltration equationsThe usage of reformulated tgrav improves predictions of soil hydraulic parameters [ABSTRACT FROM AUTHOR]

Paints are the protective and aesthetic skin of buildings, so (re) painting is one of the most recurrent maintenance actions. Limewashes have been used since antiquity and are currently of high interest for both conservation and new construction, majorly thanks to their eco-friendly and antiseptic features, and ability to improve the performance of the materials in relation to water transport. Linseed oil is a traditional water-repellent additive that can enhance the water-shedding properties of the limewashes. However, it has the risk of altering the drying kinetics of the substrate if an improper dosage is used. In this work, limewashes with the addition of varying dosages of linseed oil have been applied on two types of natural stone to study the effect of the paints in respect to water and salt transport. The water absorption by capillarity was reduced in both stones coated with pure limewash and limewash with oil, while the drying rate was slightly accelerated. The effect of the paints on the drying of the salt-laden stones varied. The salt damage developed during drying also diverged in both stones, damaging the coats and stone surface of the less porous stone and mainly promoting salt efflorescence in the most porous one. [ABSTRACT FROM AUTHOR]

We consider a fractional version of Gauß capillarity energy. A suitable extension problem is introduced to derive a boundary monotonicity formula for local minimizers of this fractional capillarity energy. As a consequence, blow-up limits of local minimizers are shown to subsequentially converge to minimizing cones. Finally, we show that in the planar case there is only one possible fractional min- imizing cone, the one determined by the fractional version of Young’s law. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gravity-capillary waves at the water surface are an obvious example illustrating wave propagation in the laboratory, and also nonlinear wave phenomena such as wave interactions or wave turbulence. However, at high-enough frequencies or small scales (i.e., the frequencies typically above 4 Hz or wavelengths below 10 cm), the viscous dissipation cannot be neglected, which complicates experimental, theoretical, and numerical approaches. In this review, we first derive, from the fundamental principles, the features of the gravity-capillary waves. We then discuss the origin and the magnitude of the viscous wave. dissipation in the laboratory and under field conditions. We then show that the significant level of dissipation has important consequences on nonlinear effects involving waves. The nonlinearity level quantified by the wave steepness must be large enough to overcome the viscous dissipation. Specifically, using water as fluid in the field and in the laboratory, nonlinear wave interactions and wave turbulence occur most of the time in a non-weakly nonlinear regime, when the waves are in the capillary or gravity-capillary range. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with the inflow problem in the half line (0 , ∞) to the isentropic compressible Navier-Stokes-Korteweg system. We first show existence and asymptotic stability of the stationary solutions to the inflow problem. Also, for shock wave, asymptotic profile of the inflow problem is shown to be a shifted viscous shock profile, which is suitably away from the boundary, and we prove that if the initial data around the shifted viscous shock profile and the strength of shifted viscous shock profile are sufficiently small, then the inflow problem has a unique global strong solution, which tends to the shifted viscous shock profile as time goes to infinity. Moreover, we show the stability of superposition viscous shock profiles and stationary solutions. The analysis is based on the elementary L 2 -energy method, but various techniques are introduced to establish the uniform boundary and energy estimates. [ABSTRACT FROM AUTHOR]

The aim of this work is to compare two methods of incorporation of concrete recycled coarse aggregate (CRCA) in the concrete mixture: at the beginning and at the end of the mixing stage. Concrete mixtures with 0% and 50% of CRCA were developed, with three water/cement (w/c) ratios. Slump loss and electrical resistivity were measured in the fresh state. Compressive strength and water absorption by capillarity were also measured in the hardened state, after 28 days of wet curing. Mixture water absorption by CRCA during mixing was decreased when the insertion was at the end of the mixture, as evidenced by better reduced slump loss. Electrical resistivity measurements are also consistent with this observation. Capillarity absorption and compressive strength, however, showed better results when CRCA was inserted at the start, due to the reduction of w/c ratio caused by the CRCA water absorption during mixing. [ABSTRACT FROM AUTHOR]

In the first main result of this paper we prove that one can approximate discontinious solutions of the 1d Navier Stokes system with solutions of the 1d Navier-Stokes-Korteweg system as the capilarity parameter tends to 0. Moreover, we allow the viscosity coefficients μ = μ (ρ) to degenerate near vaccum. In order to obtain this result, we propose two main technical novelties. First of all, we provide an upper bound for the density verifing NSK that does not degenerate when the capillarity coefficient tends to 0. Second of all, we are able to show that the positive part of the effective velocity is bounded uniformly w.r. t. the capillary coefficient. This turns out to be crucial in providing a lower bound for the density. The second main result states the existene of unique finite-energy global strong solutions for the 1d Navier-Stokes system assuming only that ρ0, 1/ρ0 ∈ L ∞. This last result finds itself a natural application in the context of the mathematical modeling of multiphase flows. [ABSTRACT FROM AUTHOR]

We study the relationship between financial development and economic growth across 110 European regions from 1997 to 2018. We single out two dimensions of financial development in the data capturing the capillarity of bank branches and the agglomeration of the financial industry at large and study their relationship with regional economic growth. To establish a causal nexus, we employ two‐ways fixed effects, instrumental variables, and the Arellano–Bond estimator. Our estimates indicate that what matters the most for regional economic growth is the agglomeration of a complex financial sector rather than the mere presence of bank branches. [ABSTRACT FROM AUTHOR]

Micro‐ and nanotexturization of surfaces can give to the parts different advanced functionalities, such as superhydrophobicity, self‐cleaning, or antibacterial capabilities. These advanced properties in combination with the biocompatibility of Liquid Silicone Rubber are an interesting approach for obtaining high‐performance medical devices. The industrial production of surface textures in polymeric materials is through the replication technique, and the best option to attain a high production rate is injection molding. Moreover, its low viscosity during processing can provide an accurate replication capacity by the easy filling by capillarity of the microtextures. An innovative replicating technique for Liquid Silicone Rubber is presented by studying the replication of different shaped textures within a diameter range of between 2 and 50 µm. The copying process consists in the overmolding of a textured polymeric inlay obtained by nanoimprint lithography. At the end of the process, a textured part is obtained, while the imprinted film remains in the mold. The injection molding parameters are optimized to increase the replication accuracy, and their effect on texture replicability is analyzed and discussed. Finally, it is shown that the textured surfaces improve their wettability behavior, which is a necessary and important characteristic in the development of biomedical devices. [ABSTRACT FROM AUTHOR]

Drop-on-demand (DOD) printing is a versatile manufacturing tool, which has been widely used in applications ranging from graphic products to manufacturing of ceramics, even for cell engineering. However, the existing DOD methods cannot be applied for highly viscous materials: the printing technologies are typically limited to the inks with the water level viscosity and fall short to eject jets from thick fluids and break them into droplets. To address this challenge, a new wire-in-a-tube technology for drop generation has been developed replacing the nozzle generator with a wire-in-a-tube drop generator. We successfully formed droplets on demand from highly viscous (∼10 Pa s) liquids and studied the mechanisms of drop formation in the wire-in-a-tube drop generators. These mechanisms couple unique fluid mechanics, capillarity, and wetting phenomena providing a new platform that can be used in different microfluidic applications. [ABSTRACT FROM AUTHOR]