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The purpose of this paper is to present a practical way to create three kinds of double emulsions such as double emulsion, double-component double emulsion and viscoelastic double emulsion.

A hierarchical T-junction microfluidic device is selected to simulate this phenomenon. A system of the three-phase flows consists of the inner, middle and outer phases were simulated by the direct numerical simulation (DNS) method. The dripping regime is considered for the droplet formation in both T-junctions. The adaptive mesh refinement technique is used to simulate the droplet formation and determine the interface rupture.

The one-step and two-step encapsulation are used to create the double emulsion and the viscoelastic double emulsion, respectively. In both T-junctions, droplets are created by the balance of three parameters which are instability, viscous drag and pressure buildup. The one-step formation of double emulsion is presented for encapsulates the viscoelastic fluid.

The simulated hierarchical microchannel shows some desirable features for creating the complex compounds. The encapsulation process is simulated in micro-scale that is useful for drug delivery applications.

In this study, which is divided into two parts, the silicone softeners having different properties and including different additives as glycerin, polyethylene glycol 400 (PEG 400) and polyethylene glycol 4000 (PEG 4000) (due to their high hydrophilic characters) are produced for the purpose of providing or developing the hydrophilic character, lubricity and filling properties of the emulsions. The paper aims to discuss this issue.

In the first part of the study, the produced silicone emulsions were characterized and applied to the 100 percent cotton-knitted fabrics. In addition, the mechanical properties and whiteness degrees of the fabrics were also researched. In this part of the study, the effects of the produced silicone softeners on the comfort properties of the fabric samples were investigated by qualitative handle, hydrophility, contact angle, air permeability, thermal comfort and moisture management tests.

The results showed that while classic silicone application improved mechanical comfort properties of the samples such as the handle and drape properties, they worsened other thermal comfort properties as hydrophility, transfer or dispersion of the moisture, and air permeability. In addition, the thermal comfort properties about heat transfer of the fabric samples were not significantly affected by application of the silicone softeners. All results were affected from the producing recipe of the silicone softeners, and generally the usage of the additives had positive effect on the comfort results depending on the producing recipe (especially type of the silicone oil) of the silicone softeners.

In this study, the additives were used in single form; however, their dual or trio combinations and/or their different amounts can be used in the emulsions.

In order to enhance the hydrophilic character, lubricity and filling properties of the silicone softeners, they could be produced by using appropriate additives.

In the literature, there were not any studies about the silicone softeners including different additives. So the authors can say that the contribution of the additives to the recipes of the silicone softeners is a novel approach.

Monodisperse microfluidic emulsions – droplets in another immiscible liquid – are beneficial to various technological applications in analytical chemistry, material and chemical engineering, biology and medicine. Upscaling the mass production of micron-sized monodisperse emulsions, however, has been a challenge because of the complexity and technical difficulty of fabricating or upscaling three-dimensional (3 D) microfluidic structures on a chip. Therefore, the authors develop a fluid dynamical design that uses a standard and straightforward 3 D printer for the mass production of monodisperse droplets.

The authors combine additive manufacturing, fluid dynamical design and suitable surface treatment to create an easy-to-fabricate device for the upscaling production of monodisperse emulsions. Considering hydrodynamic networks and associated flow resistance, the authors adapt microfluidic flow-focusing junctions to produce (water-in-oil) emulsions in parallel in one integrated fluidic device, under suitable flow rates and channel sizes.

The device consists of 32 droplet-makers in parallel and is capable of mass-producing 14 L/day of monodisperse emulsions. This convenient method can produce 50,000 millimetric droplets per hour. Finally, the authors extend the current 3 D printed fluidics with the generated emulsions to synthesize magnetic microspheres.

Combining additive manufacturing and hydrodynamical concepts and designs, the authors experimentally demonstrate a facile method of upscaling the production of useful monodisperse emulsions. The design and approach will be beneficial for mass productions of smart and functional microfluidic materials useful in a myriad of applications.

The purpose of this study is to perform a detailed review on the numerical modeling of multiphase and multicomponent flows in microfluidic system using phase-field method. The phase-field method is of emerging importance in numerical computation of transport phenomena involving multiple phases and/or components. This method is not only used to model interfacial phenomena typical to multiphase flows encountered in engineering and nature but also turns out to be a promising tool in modeling the dynamics of complex fluid-fluid interfaces encountered in physiological systems such as dynamics of vesicles and red blood cells). Intrinsically, a priori unknown topological evolution of interfaces offers to be the most concerning challenge toward accurate modeling of moving boundary problems. However, the numerical difficulties can be tackled simultaneously with numerical convenience and thermodynamic rigor in the paradigm of the phase field method.

The phase-field method replaces the macroscopically sharp interfaces separating the fluids by a diffuse transition layer where the interfacial forces are smoothly distributed. As against the moving mesh methods (Lagrangian) for the explicit tracking of interfaces, the phase-field method implicitly captures the same through the evolution of a phase-field function (Eulerian). In contrast to the deployment of an artificially smoothing function for the interface as used in the volume of a fluid or level set method, however, the phase-field method uses mixing free energy for describing the interface. This needs the consideration of an additional equation for an order parameter. The dynamic evolution of the system (equation for order parameter) can be described by Allen–Cahn or Cahn–Hilliard formulation, which couples with the Navier–Stokes equation with the aid of a forcing function that depends on the chemical potential and the gradient of the order parameter.

In this review, first, the authors discuss the broad motivation and the fundamental theoretical foundation associated with phase-field modeling from the perspective of computational microfluidics. They subsequently pinpoint the outstanding numerical challenges, including estimations of the model-free parameters. They outline some numerical examples, including electrohydrodynamic flows, to demonstrate the efficacy of the method. Finally, they pinpoint various emerging issues and futuristic perspectives connecting the phase-field method and computational microfluidics.

This paper gives unique perspectives to future directions of research on this topic.

The use of polysaccharides increases solubility and consistency and causes functions such as viscosity? Moisture and food emulsifier stabilizer. This study aims to enrich the formulation of low-fat mozzarella cheese using microcoated vitamin D3 (VD3).

This study investigates the addition of hydrocolloids to low-fat mozzarella cheese to enhance its properties and nutritional value. Tests were conducted on cheese samples with 0.05% and 0.25% hydrocolloid concentrations at various stages: before production and at three and six months’ postproduction. The samples were evaluated for elasticity, pH and solubility to select the best one, which was then fortified with VD3. The vitamin was microencapsulated using alginate and whey protein to shield it from light and oxygen, optimizing the formula using the response surface method. The fortified cheese was tested for VD3 content over its shelf life.

Results indicated that all hydrocolloids tested improved moisture and meltability of the cheese while higher protein levels increased stretchability two to threefold. Rice starch hydrocolloid at 0.05% concentration was chosen due to superior sensory scores and minimal oil separation. This study concluded that VD3 levels remained stable during the cheese’s shelf life, suggesting that this approach could enhance the nutritional value of low-fat cheese without compromising its quality. Therefore, after examining the obtained results and comparing the regression models, the results indicated that the Quadratic model was chosen to investigate the effect of independent variables on the response rate, which had a statistically significant difference with other models (p = 0.0019). Also the results of the area under the curve and using the encapsulation efficiency equation, the percentage of microencapsulated vitamin was obtained, and according to the simulation results, the encapsulation efficiency was reported as 89.02%.

Developing innovative functional dairy products fortified with VD3 could improve the vitamin D status in deficient populations. Therefore, these designs can be applied at industrial scales for functional cheese production.

This study aims to develop an experimentally validated three-dimensional numerical model for predicting different flow patterns produced with a gas dynamic virtual nozzle (GDVN).

The physical model is posed in the mixture formulation and copes with the unsteady, incompressible, isothermal, Newtonian, low turbulent two-phase flow. The computational fluid dynamics numerical solution is based on the half-space finite volume discretisation. The geo-reconstruct volume-of-fluid scheme tracks the interphase boundary between the gas and the liquid. To ensure numerical stability in the transition regime and adequately account for turbulent behaviour, the k-ω shear stress transport turbulence model is used. The model is validated by comparison with the experimental measurements on a vertical, downward-positioned GDVN configuration. Three different combinations of air and water volumetric flow rates have been solved numerically in the range of Reynolds numbers for airflow 1,009–2,596 and water 61–133, respectively, at Weber numbers 1.2–6.2.

The half-space symmetry allows the numerical reconstruction of the dripping, jetting and indication of the whipping mode. The kinetic energy transfer from the gas to the liquid is analysed, and locations with locally increased gas kinetic energy are observed. The calculated jet shapes reasonably well match the experimentally obtained high-speed camera videos.

The model is used for the virtual studies of new GDVN nozzle designs and optimisation of their operation.

To the best of the authors’ knowledge, the developed model numerically reconstructs all three GDVN flow regimes for the first time.

The purpose of this article was to highlight the various methods of extrusion technologies for encapsulation of bioactive components (BACs).

BACs provide numerous health-care benefits; however, downsides, including a strong effect of organoleptic properties by reason of the bitterness and acridity of a few components, and also a short shelf-life, limit their application in food. The food industry is still demanding complicated qualities from food ingredients, which were often impossible to obtain without encapsulation such as stability, delayed release, thermal protection and an acceptable sensory profile. Various techniques such as melt injection extrusion, hot-melt extrusion, electrostatic extrusion, co-extrusion and particles from gas-saturated solutions, could be used for maintaining these characteristics.

Extrusion technology has been well used for encapsulation of bioactive chemicals in an effort to avoid their numerous downsides and to boost their use in food. The count of BACs that could be encapsulated has risen owing to the extrusion technology just as form of encapsulation. Extrusion technique also aids in the devaluation of the fragment size of encapsulated BACs, allowing for greater application in the food business.

The study reported that encapsulating BACs makes them more stable in both the product itself and in the gastrointestinal tract, so using encapsulated BACs would result in a product with stronger preventive properties.

The purpose of this paper is to study the corrosion process by examining the deterioration of X80 steel exposed to a real petroleum sample containing condensed hydrocarbon plus oilfield-produced water, which were subjected to stimulated emulsions in flowing media at 50°C.

The impedance and polarization spectra were used to assess the aggressiveness of the petroleum sample and tried to find a washing process using condensed hydrocarbon with deionized water. Mössbauer technique was used to identify the phases in precipitated ions obtained during an oven-drying procedure of the oilfield produced water.

The emulsion, chloride, sulphur compounds, heavy metals and the use of a double hydrodynamic system were the most important factors affecting the corrosion of X80 steel. The corrosion rate of this steel increased when oilfield-produced water was stimulated by a double hydrodynamic system (4.56 mm/year). It was determined to be 7.66 mm/year and 4.01 mm/year when steel was exposed to a stimulated emulsion using the petroleum sample and condensed hydrocarbon with deionized water at 24 h, respectively, suggesting that a significant process of hydrocarbon washing could occur and a more corrosive solution was highlighted. Mössbauer results showed that the ions precipitates included the following phases at Wt.%: magnetite (20.0), greigeite (22.8), siderite (3.2), pyrite (2.9), marcasite (26.7) and mackinawite (24.4).

A stimulated hydrocarbon/water emulsions with a more homogeneous solution containing high concentrations of saline compounds and heavy metals were used to simulate the susceptibility to corrosion on the internal pipeline steels exposed to any type of immiscible liquids such as condensed hydrocarbon, or crude oil, containing water. A practical application of the presented research could provide a novel framework for understanding the internal corrosion in pipelines from the simulation of washed hydrocarbons after the stimulated emulsions that can be found in the field. Because more susceptibility to corrosion for pipeline steels would be expected at the end of the transportation of the fluid. It is possible to investigate the possible corrosion mechanisms by using a dried oilfield-produced water sample interacting with the pipeline steels.

Fluorine materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose of this paper is to prepare fluorine-containing soap-free acrylic emulsion, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate(DFMA) were introduced as functional monomer.

The fluorinated polyacrylate emulsion was successfully prepared by semi-continuous seed emulsion polymerization, wherein the main monomers were methyl methacrylate (MMA) and butyl methacrylate (BA), and the initiator was potassium persulfate (KPS). Sodium alloxypropyl sulfonate (COPS-1) and an anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were compounded as a polymerizable emulsifier. Besides, undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as the functional monomers.

The optimum recipe of preparing the modified latex is as follows: the amount of emulsifier was 4%, the ratio of emulsifier (COPS-1: AOS) was 3: 1, and the content of initiator was 0.6%. In this case, the conversion rate of acrylic polymer emulsion was high and the polymerization stability was good. When the amount of monomer UA was 2% and the amount of DFMA was 4%, the overall performance of the emulsion was the best.

The fluorine-containing soap-free acrylic emulsion is prepared via semi-continuous seeded emulsion polymerisation, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as functional monomer. There are two main innovations. One is that the fluorine-containing soap-free acrylic emulsion is prepared successfully. The other is that the undecylenic acid is introduced as functional monomer.

The purpose of this research is to study different extra-heavy crude oil-in-water emulsions that can be found in practice for corrosion process of X52 steel adding 60 mg.L-1 of non-ionic surfactant and a corrosion inhibitor (CI). Electrochemical impedance spectroscopy and Tafel plots are carried out. Thus, Bode-modulus and Bode-phase angle plots are discussed. Adsorption isotherms obtained from corrosion rate (CR) values are taken into account.

Two-electrode arrangement is used to characterize the pseudo-capacitance values for X52 steel exposed to water and crude oil phases, mainly. Electrochemical evaluations for X52 steel exposed to extra-heavy crude oil-in-water emulsions are recorded in a conventional three-electrode cell to study the corrosion process as was documented in detail by Quej-Ake et al. (2015). Therefore, all electrodes are placed as close as possible to eliminate the iR-drop.

Pseudo-capacitance analysis shows that X52 steel immersed in oilfield produced water was more susceptible to corrosion than that immersed in ocean water solution and extra-heavy crude oil phase. After being analyzed, the X52 steel surface coverage and adsorption process for surfactant and CI could be concluded that surfactant could protect the metal surface. In a coalescence extra-heavy crude oil-in-water emulsion, the water medium generated a new solution that was more corrosive than the original water phase. Wash crude oil process was provoked in emulsion systems to sweep up the salts, mainly. Thus, corrosive species that can be recovered inside extra-heavy crude oil may appear, and in turn a new more corrosive solution could be obtained. Taking into account the straight line obtained in Bode-modulus plot for X52 exposed to extra-heavy crude oil, it is possible to point out that the negative value of the slope or R² can be related to a coefficient (Jorcin et al., 2006). It is important to mention that electrochemical responses for X52 steel exposed to extra-heavy crude oil-in-water under coalescence emulsions revealed that corrosion and diffusion processes exist. Therefore, a possible good inhibitor is surfactant in emulsion systems.

CR and anodic and cathodic slopes suggest that the surfactant acted as mixed CI. Of these, susceptible anodic (MnS and perlite or cementite) and cathodic (ferrite) sites on steel surface could be affected, due to which physicochemical adsorption could happen by using electrochemical parameters analysis. Thus, no stable emulsions should be taken into account for extra-heavy crude oil transportation, because corrosion problems in atmospheric distillation process of the crude oil due to stable emulsion cannot be easily separated. In this manner, coalescent emulsions are more adequate for transporting extra-heavy crude oil because low energy to separate the water media is required.