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• The influence of particle fluid dynamics in S/L reactive capture systems is analysed. • Microfluidic chromate uptake by amino-functionalized particles as case study. • Successful experimental validation of Euler-Lagrange model with error inferior to 10% • Comparison of simulated data with E-L and two fluids E-E model. Micro- and nano- sized particles display an outstanding performance in the selective capture or release of molecules after the target species is contacted. Microfluidics can hugely benefit the performance of these systems given the remarkable features it presents. In this work, to the best knowledge of the authors, the microfluidic solid/liquid selective interfacial mass transfer is tackled for the first time in a Computational Fluid Dynamics (CFD) model based on the Euler-Lagrange framework. To gain insight on the effect of describing the particles as discrete entities, another model with the same purpose has been developed under the Euler-Euler approach. To experimentally validate and test the performance of the models, the microfluidic capture of chromate ions employing amino-functionalized particles in a Y-Y shaped microdevice has been selected as case study. Both models have been successfully validated, providing a relative root-mean-square error (RRMSE) of 9.86% for the Euler-Lagrange model and 22.62% for the Euler-Euler one. The performance of both models has been tested through a set of simulations in which the residence time and the load of particles are varied. The Euler-Euler option overestimates the hexavalent chromium removal in the kinetic region up to 27.94%, although both provide equally precise equilibrium data. The prediction difference between models is more significant when higher particle loads are used. Therefore, it is concluded that the Euler-Lagrange model proves to be a reliable and highly resourceful tool to predict the behavior of microfluidic multiphasic systems in a wide range of conditions. [ABSTRACT FROM AUTHOR]

The surface charge of gallium nitride (GaN) in contact with solution is controlled by pH via surface protonation and deprotonation, similar to silica. Ionic surfactants adsorb on surfaces via electrostatic and hydrophobic interactions and can be utilized to reflect the surface charge of GaN. The surface charge properties of Ga-polar GaN in solution were probed as a function of pH using atomic force microscopy (AFM). AFM soft-contact images and force curves were used to study the pH-dependent adsorption of the cationic surfactant cetyltrimethylammonium bromide (CTAB) and anionic surfactant sodium dodecylsulfate (SDS) on GaN surfaces. To further confirm the AFM results, GaN/AlGaN/GaN heterostructure-based ion sensing devices were used to measure the surfactant adsorption over the same pH range. SDS aggregates adsorb on GaN below pH 2.75 while CTAB aggregates adsorb above pH 10. This shows that the GaN surface carries substantial net positive charge at low pH, and negative charge at high pH. There is no clear SDS or CTAB adsorption on the GaN surface between pH 3 and 9.75, which indicates the surface is weakly charged. GaN/AlGaN/GaN heterostructure-based devices confirm these results, and demonstrate the utility of these devices for measuring surfactant adsorption. [ABSTRACT FROM AUTHOR]

Here we report on a scanning tunnelling microscopy (STM) investigation on the self-assembly of C 3 - and C 2 -symmetric molecules at the solution/graphite interface. 1,3,5-tris(( E )-2-(pyridin-4-yl)vinyl)benzene and 1,1,2,2-tetrakis(4-(pyridin-4-yl)phenyl)ethane are used as model systems. These molecules displayed a concentration dependent self-assembly behaviour on graphite, resulting in highly ordered supramolecular structures, which are stabilized jointly by van der Waals substrate-adsorbate interactions and in-plane intermolecular H-bonding. Denser packing is obtained when applying a relatively high concentration solution to the basal plane of the surface whereas a less dense porous network is observed upon lowering the concentration. We show that the molecular conformation does not influence the stability of the self-assembly and a twisted molecule can pack into dense and porous architectures under the concentration effect. [ABSTRACT FROM AUTHOR]

In China, there is an urgent need for an efficient anaerobic digester to sustainably treat rice straw. In this study, a downward plug-flow anaerobic digester (DPAD) was designed in which the total working core is separated into three sections: an upper liquid zone, a lower liquid zone, and a solid-state bed (SSB) in the middle. A solid/liquid separation mechanism was designed to recirculate liquor and the discharged solid residue after complete digestion. The 70-L DPAD was run indoors for 100 d, time in which chopped rice straw (30 to 50 mm in length) was fed every 20 d. The digestion performance and biogas production were analysed to assess the feasibility for practice application. The results showed that the DPAD can control scum formation and offers a methane yield of 162.60 L/kg volatile solids, 21.1% higher than that of the control test. It was also found that straw was continuously and efficiently digested by the DPAD in 3 experimental stages. Methane production rates increased by 76.30%, 57.37%, and 13.33% on the second day compared to the first day, respectively, and then, all decreased as the substrate was gradually exhausted. Based on the results, it is clear that the DPAD is a promising solution for chopped straw digestion.

The solid/liquid Li-S battery shows promise in solving both the polysulfide "shuttle effect" in liquid batteries and the interfacial contact in all-solid-state batteries. However, increasing the interfacial stability of the electrolyte and the solid electrolyte remains a challenge in the solid/liquid batteries. In this work, a high ionic conductivity Li 3 PS 4 solution is synthesized using a nano-Li 2 S precursor, which is then utilized to form a solid electrolyte Li 3 PS 4 @Li 7 P 3 S 11 via dip-coating. The Li 3 PS 4 @Li 7 P 3 S 11 can form a dense protective interface Li 3 PS 4 -DME with the DOL/DME and DME electrolyte. This interface can prevent direct contact between the solid electrolyte and the electrolytes, efficiently inhibiting further solid electrolyte decomposition. The lithium symmetric battery with the solid electrolyte Li 3 PS 4 @Li 7 P 3 S 11 is cycled stably for 1000 h, at a current density of 0.38 mA cm−2 and a capacity of 1.51 mA h cm−2. The Li-S battery with the solid electrolyte Li 3 PS 4 @Li 7 P 3 S 11 can cycle stably for 300 cycles at 0.2C with a capacity of 600 mA h g−1 remaining. • The nano-Li 3 PS 4 sol was synthesized by using nano-Li 2 S as a precursor. • A high ionic conductivity Li 3 PS 4 layer was coated on the solid electrolyte Li 7 P 3 S 11. • The DME-based electrolyte and the solid electrolyte Li 3 PS 4 @Li 7 P 3 S 11 are highly stable. • The solid electrolyte Li 3 PS 4 @Li 7 P 3 S 11 exhibited excellent cycling stability. [ABSTRACT FROM AUTHOR]

In China, there is an urgent need for an efficient anaerobic digester to sustainably treat rice straw. In this study, a downward plug-flow anaerobic digester (DPAD) was designed in which the total working core is separated into three sections: an upper liquid zone, a lower liquid zone, and a solid-state bed (SSB) in the middle. A solid/liquid separation mechanism was designed to recirculate liquor and the discharged solid residue after complete digestion. The 70-L DPAD was run indoors for 100 d, time in which chopped rice straw (30 to 50 mm in length) was fed every 20 d. The digestion performance and biogas production were analysed to assess the feasibility for practice application. The results showed that the DPAD can control scum formation and offers a methane yield of 162.60 L/kg volatile solids, 21.1% higher than that of the control test. It was also found that straw was continuously and efficiently digested by the DPAD in 3 experimental stages. Methane production rates increased by 76.30%, 57.37%, and 13.33% on the second day compared to the first day, respectively, and then, all decreased as the substrate was gradually exhausted. Based on the results, it is clear that the DPAD is a promising solution for chopped straw digestion. [ABSTRACT FROM AUTHOR]

This review deals with the main physico-chemical and interfacial processes, related to adhesion, that occur during textile manufacturing from raw material to the different final end-products. As regards the possible interfaces (solid/gas, solid/liquid and solid/solid), a number of considerations should be borne in mind in order to modulate the adhesion properties of textile materials. In the solid/gas section are presented the theoretical concepts, methods for gas adsorption determination, influence of fiber and fabric structure on gas adsorption and the influence of environmental conditions on surface group orientation. In the solid/liquid section the theoretical aspects and practical considerations related to detergency, solid–liquid interactions, surface roughness, lotus effect in self-cleaning surfaces and wicking in textile substrates are presented. Finally, in the solid/solid section are described the principles of adhesion, conditions for good adhesion and the incorporation of microcapsules and nanoparticles into textile substrates. [ABSTRACT FROM AUTHOR]

Abstract: Li+-ion and Na+-ion transfer at interfaces composed of inorganic solid electrolytes and polymer or organic liquid electrolytes were compared. La0.55Li0.35TiO3 and Na3Zr1.88Y0.12Si2PO12, which are conductive for Li+ and Na+, were selected for use as inorganic solid electrolytes. PC solution and PEO-based polymer electrolytes were added to Li salt or Na salt to give ionic conductivity. Using these electrolytes, solid electrolyte/liquid electrolyte or solid electrolyte/polymer electrolyte interfaces were constructed. The resistivities of Li+ or Na+ transfer through these interfaces were estimated based on the results of ac impedance measurements. In both solid/liquid and solid/polymer systems, the activation energies of Na+-ion transfer at the interface were smaller than those of Li+-ion. The Lewis acidity of both ions, Li+ and Na+, clearly explains this difference and supports the idea that the interaction between ion and solvents plays a major role in interfacial ion-transfer processes. [Copyright &y& Elsevier]

[Display omitted] • The structure of reservoir clay minerals affecting the fluids deformation in reservoir sandstone. • Factor influencing the propensity to disperse or migrate as aqueous suspensions in pore fluids varying the NaCl electrolyte concentration. • Ions distribution in reservoir sandstone under electric double layers. • The ionic strength species and ion transport formation in reservoir environment. The dielectric properties of reservoir sandstone are controlled by several physical factors such as the size, conductivity, the mineral types, and interaction between the particles are the major constrain in reservoir sandstone. The key issues are the accumulation of ions at the interface between two immiscible liquids (oil/water), solid/liquid interface, and ion separation in terms of polarization mechanisms. This review article discussed in detail the mineralogy overview, the factor responsible for the polarization mechanisms in reservoir sandstone, electric double layer propagation, electrical conduction in reservoir sandstone, the effect of electromagnetic filed within the reservoir sandstone, the cation and anion exchange within the electric double layers for the reduction of interfacial tension in reservoir sandstone, and the complexity of reservoir response with the presence of oil and electrolyte to the electromagnetic field. frequency dependence gives us the clue on the fluid mobility concerning the electromagnetic field. The distribution of cation and anion within the solid/liquid interface are well elucidated due to dielectric relaxation spectral illustration. [ABSTRACT FROM AUTHOR]

A numerical model of the solid/liquid phase change problem in porous media and free fluids is presented in this paper for the first time by employing a modified version of the generalized porous medium model, in 2D and 3D, solved by means of the Characteristic-Based-Split (CBS) scheme. The proposed procedure is based on the solution of one set of equations to describe different phenomena: natural convection in porous media, solidification and melting both in porous media and in free fluids. The generalized model has been modified to incorporate the apparent heat capacity, source term and pseudo-viscosity methods in order to reproduce phase change phenomena. Two versions of the algorithm, the Semi-Implicit (SI) and the Quasi-Implicit (QI) schemes, have been developed to solve the governing equations, and validated against numerical and experimental data available in the literature. The two schemes have been compared in terms of accuracy and efficiency for the solution of the benchmark problems. [ABSTRACT FROM AUTHOR]