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Emulsion systems are extensively used in the food processing sector and the use of natural emulsifiers like proteins for stabilizing emulsion has been in demand from consumers due to increased awareness about the consumption of healthy food. Numerous methods are available for the preparation of emulsion, but ultrasound got more attention among common methods owing to its economical and environment-friendly characteristics. The physical effects caused by to bursting of the cavity bubble, result in reduced droplet size, thus forming an emulsion with appreciable stability. Ultrasound ameliorates the emulsifying characteristics of natural emulsifiers like protein and improves the storage stability of the emulsion by positively boosting the rheological, emulsifying characteristics, improving zeta potential, and reducing average droplet size. The stability of protein-based emulsion is affected by environmental stresses hence conjugate of protein with polysaccharide showed good emulsifying characteristics. However, the data on the effect of ultrasound parameters on emulsifier properties is lacking and there is a need to develop a sonication device that can carry out large-scale emulsification operation. The review covers the principles and mechanisms of ultrasound-assisted formation of protein-based and protein-based conjugate emulsions. Further, the effect of ultrasound on various characteristics of protein-based emulsion is also explored. This review will provide concise data to the researchers to extend their experiments in the area of ultrasound emulsification which will help in commercializing the technology at the industrial scale.

During recent years, the development of drug delivery systems based on polymers has created powerful carriers for smart application in nanomedicine for the treatment of diseases. Based on this, the design of polymers that contain various active functional groups to create a suitable interaction with the drug for its loading and release has been considered. Generally, more porosity for more drug loading, biocompatibility of the desired polymer and more water absorption lead to better performance in drug permeation and release.In this research, the preparation of a template with a high internal phase emulsion (PolyHIPEs) based on polyacrylamide grafting onto sodium alginate (SA) biopolymer via free radical polymerization and PolyHIPEs method of oil-in-water emulsion type is presented. In this work, porous hydrogel with high water swelling (absorption) was prepared by using different concentrations of acrylamide (AAm), surface active agent, cross-linking agent and initiator. The highest equilibrium water swelling value of synthetic porous hydrogel with HIPEs method was 280 g/g, while the water swelling value of prepared hydrogel without HIPEs method was 25 g/g. The open-cell porous hydrogel with water swelling of 280, has average pores of 5-10 μm, 200 nm windows and porosity of 80-85%. Modern instrumental methods such as SEM, AFM, FT-IR, BET and TGA were used to identify the porous hydrogel of PolyHIPEs. The loading and controlled release of the doxorubicin anticancer drug was performed on the optimum porous hydrogel in laboratory conditions. The results showed that smart SA-g-PAAm hydrogel is suitable for drug release at 41 °C and pH 5.5 (cancer cell conditions).

In the present study, a series of semisolid Oil in Water (O/W) emulsions containing different Curcumin (Cur) derivatives (Cur powder, Cur extract and Cur complexed with β-cyclodextrin) in varying concentrations, were prepared. Initially, Dynamic Light Scattering (DLS), microscopy, pH and viscosity measurements were performed to evaluate their stability over time. Moreover, the effect of the active cosmetic substances on the Sun Protection Factor (SPF), antimicrobial and antioxidant properties of the prepared emulsions was investigated. It was observed that emulsions containing Cur extract and Cur β-cyclodextrin complex presented great viscosity and pH stability for up to 90 days of storage contrary to the emulsions containing Cur powder which showed unstable behavior due to the formation of agglomerates. All samples presented SPF values between 2.6 and 3.2. The emulsions with Cur in all forms exhibited high antioxidant activity, whereas the emulsion containing Cur β-cyclodextrin complex presented the highest value. Despite their improved stability and antioxidant activity, the emulsions containing Cur extract and Cur-β-cyclodextrin exhibited a low percentage of antimicrobial activity against E. coli and Staphylococcus bacteria. Instead, the emulsions containing Cur powder presented a reduction rate over 90 % against E. coli and Staphylococcus colonies. [ABSTRACT FROM AUTHOR]

• Proteins can be used as emulsifiers due to their amphiphilic nature. • Cavitation events in sonication reduce the droplet size of the emulsion and enhance its stability. • Ultrasound ameliorates the emulsifying characteristics of natural emulsifiers like protein and improves the storage stability of the emulsion. • The study on sonication-assisted formation of protein-based stable emulsion is still limited. Emulsion systems are extensively used in the food processing sector and the use of natural emulsifiers like proteins for stabilizing emulsion has been in demand from consumers due to increased awareness about the consumption of healthy food. Numerous methods are available for the preparation of emulsion, but ultrasound got more attention among common methods owing to its economical and environment-friendly characteristics. The physical effects caused by to bursting of the cavity bubble, result in reduced droplet size, thus forming an emulsion with appreciable stability. Ultrasound ameliorates the emulsifying characteristics of natural emulsifiers like protein and improves the storage stability of the emulsion by positively boosting the rheological, emulsifying characteristics, improving zeta potential, and reducing average droplet size. The stability of protein-based emulsion is affected by environmental stresses hence conjugate of protein with polysaccharide showed good emulsifying characteristics. However, the data on the effect of ultrasound parameters on emulsifier properties is lacking and there is a need to develop a sonication device that can carry out large-scale emulsification operation. The review covers the principles and mechanisms of ultrasound-assisted formation of protein-based and protein-based conjugate emulsions. Further, the effect of ultrasound on various characteristics of protein-based emulsion is also explored. This review will provide concise data to the researchers to extend their experiments in the area of ultrasound emulsification which will help in commercializing the technology at the industrial scale. [ABSTRACT FROM AUTHOR]

In the current research, ultrasound was applied to make whey protein isolate (WPI)-gardenia fruit oil nanoemulsion. Effects of preparation conditions on physicochemical characteristics of nanoemulsions were investigated. The smallest droplet size was obtained at the oil content of 10% (v / v) and the WPI concentration of 0.5% (w / v) with ultrasound (2.4 W/mL, 12 min). Ultrasound led to a more uniform nanoemulsion with smaller droplet sizes (< 300 nm). The nanoemulsion prepared with ultrasound remained relatively stable for more than one week, while the crude emulsion prepared without ultrasound layered after 1 day storage. The nanoemulsion was more stable at lower temperature, alkaline condition and lower Na+ concentration. The formation of nanoemulsions significantly reduced the generation rate and amount of POV and TBARS during the 14-day accelerated oxidation experiment, increasing the oxidation stability of gardenia fruit oil. Additionally, the nanoemulsion could encapsulate β-carotene, hesperetin and naringenin at the efficiency of 79.61%, 51.29% and 46.06%, which further improved the oil oxidation stability and retarded free fatty acids release during the stimulated digestion in vitro. [Display omitted] • Ultrasound decreased the droplet size and improved the stability of nanoemulsions. • The nanoemulsion was stable at low temperature, Na+ concentration and basic condition. • Loading β-carotene, hesperetin and naringenin retarded oil oxidation and FFA release. [ABSTRACT FROM AUTHOR]

In the present study, a series of semisolid Oil in Water (O/W) emulsions containing different Curcumin (Cur) derivatives (Cur powder, Cur extract and Cur complexed with β-cyclodextrin) in varying concentrations, were prepared. Initially, Dynamic Light Scattering (DLS), microscopy, pH and viscosity measurements were performed to evaluate their stability over time. Moreover, the effect of the active cosmetic substances on the Sun Protection Factor (SPF), antimicrobial and antioxidant properties of the prepared emulsions was investigated. It was observed that emulsions containing Cur extract and Cur β-cyclodextrin complex presented great viscosity and pH stability for up to 90 days of storage contrary to the emulsions containing Cur powder which showed unstable behavior due to the formation of agglomerates. All samples presented SPF values between 2.6 and 3.2. The emulsions with Cur in all forms exhibited high antioxidant activity, whereas the emulsion containing Cur β-cyclodextrin complex presented the highest value. Despite their improved stability and antioxidant activity, the emulsions containing Cur extract and Cur-β-cyclodextrin exhibited a low percentage of antimicrobial activity against E. coli and Staphylococcus bacteria. Instead, the emulsions containing Cur powder presented a reduction rate over 90 % against E. coli and Staphylococcus colonies.

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Filtration is a purification stage that eliminates the suspended solids and remnants of oils present in water. This separation process has its main foundation through the use of a medium with suitable porosity and permeability characteristics with the purpose of implementing new alternatives during the treatment. Therefore, the use of coconut husk (Cocos nucifera) was evaluated as an alternative filter medium in the water treatment of El Salto Oilfield. For this purpose, a characterization of the original process water conditions was performed, as well as the pulverization of the coconut shell, followed by the consequent selection of particles of 1 mm, 2 mm and 3 mm implemented to measure the effectiveness of the filtration process. Once the research was developed, it was observed that the application of a particle size 2 mm generated a decrease in the concentration of suspended solids from 170 mg/L to 53 mg/L, representing an efficiency of 68,82%. On the other hand, the decrease in the concentration of oils in water showed an efficiency of 98,55%, concluding that the pulverized organic material in a particle size of 2 mm is a viable alternative that would represent a reduction in treatment costs. [ABSTRACT FROM AUTHOR]

Electrocoagulation with electrical polarity inversion was used to treat oil in water emulsions (145 ± 5 mg dm−3) using a cylindrical 4.8 dm3 reactor in continuous mode. The effects of spatial time and time between polarity inversion were explored using a three-level full factorial design (32), followed by Spearman correlation (p s), which has shown that the aluminum concentration in the treated effluent is not directly dependent on the mass of aluminum released by the electrodes. Nonetheless, the loss of mass of the electrodes is correlated (p s = 0.6970) to oil removal and to less electric power consumption (p s = −0.6909). Surface response analysis revealed that increasing the number of inversion cycles reduces electrode degradation. The treatment reduced the effluent's chemical oxygen demand by over 92.8%. Regarding environmental impact, there is an inverse statistical correlation between aluminum in the treated effluent and oil removal (p s = −0.7426), indicating that removing more oil with less environmental impact is possible. The better condition, considering oil removal and lower electrode consumption, was obtained with a spatial time of 36 min and a polarity inversion time of 10 s; for this condition, oil removal reached 87.0% with an energy expenditure of about 7.21 kW h.m−3. [Display omitted] • Oil in water removal by electrocoagulation with a polarity switch was investigated. • Al in the final effluent is not correlated to the Al mass lost by the electrodes. • The number of cycles of polarity inversion alters electrode degradation. • Final pH and oil removal are inversely correlated to the amount of Al liberated. [ABSTRACT FROM AUTHOR]

Abstract This paper deals with the evaporative characteristics and engine test results of emulsified fuels composed of diesel and hydrogen peroxide to reduce engine emissions by means of fuel design. The purpose of this study is basic research for applying emulsified fuel (EF) to engine through investigating the change of properties of emulsified fuel and the analysis of the behavior characteristics of free and impinging spray. In addition, the results are applied to real engine and the results of the study are presented comprehensively. To make the emulsified fuel for the experiment, the surfactant for mixing the emulsified fuel was fixed at a mixing ratio of 3% (vol.) of the total volume of the fuel, and Span 80 and Tween 80 were mixed at a ratio of 9:1. The mixing ratio of the hydrogen peroxide of the emulsified fuels was set to increase by 10% from EF2 to EF42 in consideration of the amount of the surfactant, and expressed as EF0 (diesel) in the case of diesel only. However, for the stable operation of the engine, the actual engine experiment was conducted only for the mixing ratios of EF0 and EF2. In order to analyze the characteristics of evaporation and engine emission reduction according to the mixing ratio of emulsified fuel, the experiments of droplet, free spray, impinging spray and actual engine were performed, respectively. Experimental images for visualization were obtained by using scattered light and Schlieren method. In the case of the droplet experiment, the evaporation characteristics were analyzed by free drop of the fuel droplet on a heating plate maintained at 473 K. The injection pressures of the emulsified fuel were set to 40 MPa, 60 MPa, 80 MPa and 100 MPa. In the case of free spray, experiment was carried out in a constant volume chamber maintained at room temperature (288 K) and 423 K. In the case of the impinging spray, the temperature of the impinged plate was changed to 423 K, 473 K and 523 K, respectively. The evaporation characteristics of the emulsified fuel were analyzed through the analysis of the fuel diffusion area and the entropy analysis based on statistical thermodynamics using the results obtained from such experiments. It was found that droplet and spray evaporation were promoted as the mixing of hydrogen peroxide in the emulsified fuel increased, and a method of quantitatively analyzing the experimental phenomenon could be proposed. From these results, it can be expected that the mixture of emulsified fuel mixed with hydrogen peroxide can be formed faster than the conventional diesel when applied to a real diesel engine. As a result, it is expected to play a positive role in terms of engine emission reduction. Based on these basic experimental results, emulsified fuels with mixing ratios of EF0 and EF2 were applied to diesel engine and actual engine test was conducted. NOx and soot were reduced by rapid mixture formation due to the fuel evaporation promoting effect as well as the effect of lowering the temperature of the combustion chamber due to the latent heat of evaporation of the hydrogen peroxide contained in the emulsified fuel. Finally, it can be confirmed that when the proper mixture ratio of emulsified fuel is selected for main engine operation, simultaneous reduction of NOx and soot is possible. [ABSTRACT FROM AUTHOR]

A study conducted in Egypt during 2017 to describe preparation of oil-in-water (O/W) nanoemulsions for different insecticides through ultrasonic emulsification technique. The stability of nanoemulsions over a time period, polydispersity index, droplet size, viscosity, and pH were investigated. The results of dynamic light scattering measurements showed that prepared nanoemulsions had a droplet size distribution of lower than 200 nm. The particle size of chlorpyrifos, malathion, cypermethrin, deltamethrin and lambda-cyhalothrin was 18.35, 177.2, 84.99, 24.42 and 79.05 nm, respectively with PDI values from 0.121 to 0.377. The transmission electron microscopy confirmed that these nanoparticles have spherical shape. The viscosity of all formulations ranged from 2.00 to 27.23 mPa.s and pH was around 6.0. The prepared nanoemulsions remained stable over four months of storage at room temperature. This result proved that all selected insecticides were successful in their preparation with a nanometric size range indicating to the possibility of developing suitable formulations as alternatives to traditional emulsifiable concentrate formulations. [ABSTRACT FROM AUTHOR]

Cellulose Nanocrystals (CNC) are explored to stabilize oil/water emulsions for their ability to adsorb at the oil/water interface. In this work, the role of electrostatic forces in the CNC ability to stabilize oil/water emulsions is explored using canola oil/water and hexadecane/water as model systems. Canola oil/water and Hexadecane/ water (20/80, v/v) emulsions were stabilized with the addition of CNCs using ultrasonication. Emulsion droplet sizes range from 1 to 4 μm as measured by optical microscopy. It is found that CNC can stabilize oil/water emulsions regardless of their charge density. However, reducing the surface charge density, by adding salts and varying pH, can reduce the amount of CNC's required to form a stable emulsion. Just by adding 3 mM Na+ or 1 mM or less Ca+2 to a CNC suspension, the amount of CNC reduced by 30% to stabilized 2 mL of Canola oil. On the other hand, adding salt increases the emulsion volume. The addition of 100 mM Na+ or the reduction of pH below 2 leads to the aggregation of CNC; emulsions formed under these conditions showed gel-like behavior. This work shows the potential of nanocellulose crystal in stabilizing food and industrial emulsions. This is of interest for applications where biodegradability, biocompatibility, and food grade requirements are needed.

In order to achieve the highly efficient development of heavy oil reservoirs, fatty acid alkanolamide bipolyoxyethylene ether (NS) is used to emulsify the oil spontaneously. After 12 hours' standing at the temperature of 65°C, the equal volume heavy oil can be completely emulsified in the NS solution with mass concentration of 20000 mg/L to form a oil in water emulsion. Under the action of NS, the oil-water interfacial tension can be reduced to below 10−3mN/m, the oil-water interfacial viscosity and the absolute value of the zeta potential can be increased to a higher value, which can stabilize the emulsion. The formed droplet is small and its distribution is uniform. When the salinity is less than 50000 mg/L, the properties of the emulsion is stable. The results can provide theoretical basis for field application of spontaneous emulsification flooding in heavy oil reservoirs. [ABSTRACT FROM AUTHOR]

The present study elucidates the creaming phenomenon of mineral oil-in-water macroemulsion using a new noninvasive method based on turbidimetry. Additionally, microscopic observation of the phenomenon is carried out to derive an in-depth understanding of the mechanisms. Accumulation of the particles in the emulsions under the formed cream is monitored during a relatively prolonged period of time. Backflow of continuous and dispersed phases in temporary channels is observed at the proximity of the cream. In addition to the backflow, a high traffic density of the dispersed particles and deflocculation of the cream are the main reasons for the accumulation of the dispersed phase particles and a temporary stability against creaming. The deflocculation hinders cream growth and increases the stratification of the cream. A low concentration zone of the dispersed phase with the width of ∼100 µm is observed under the cream. [ABSTRACT FROM AUTHOR]

This study is a basic research on the application of the mixed emulsified fuel of diesel and hydrogen peroxide (H2O2) to the diesel engine and investigating the evaporative characteristics of the emulsified fuel. The surfactant used to mix the emulsified fuel was added by mixing the span 80 and tween 80 with a ratio of 9:1 and being fixed to 3 % of the total volume of the emulsified fuel. The mixing ratio of the emulsified fuel was selected as EF0 (Only diesel), EF2, EF12, EF22, EF32 and EF42, respectively, considering the mixing ratio of the surfactant. To analyze the evaporative characteristics of the emulsified fuel in accordance with the mixing ratio, a drop of the emulsified fuel was freely dropped to a hot plate maintained at 473 K with a spuit and then the experimental results of the drop evaporation were visualized with the Schlieren system. Then, the quantitative image analysis of the images was introduced and it could be found that droplet evaporation was promoted according to the increase of the hydrogen peroxide in the emulsified fuel. Also, numerical analysis was performed with modeling for micro droplets in the fuel based on the experimental result, and promoted-fuel evaporation was reproduced due to the microexplosion of evaporative characteristics of emulsified fuel in accordance with the increase of the mixing ratio of hydrogen peroxide. Also, for quantitative analysis of experimental results, entropy analysis based on statistical thermodynamics was carried out. Consequently, in the case of the application of emulsified fuel to the diesel engine, it is expected to simultaneously decrease the Soot and NOx generation by speedily mixture formation and the latent heat of evaporation of the emulsified fuel in the cylinder. [ABSTRACT FROM AUTHOR]

Nanoemulsions are particularly suitable as a platform in the development of delivery systems for lipophilic functional agents. Current research describes the formation of oil-in-water (O/W) diazinon nanoemulsions using synthetic and natural additives by adopting a high-energy (ultrasound) emulsification method. The diazinon nanoemulsions were spontaneously formed by adding dropwise a mixture of diazinon, solvent and co-solvent in an aqueous solution containing a surfactant (tween or lecithin) with continuous stirring. The nanoemulsions were then formed by ultra-sonication. The effects of three levels of active ingredient, solvent, co-solvent, surfactant, sonication time and sonication cycle and power were performed by Minitab software to design the experiment. Effects of these factors on droplet size, polydispersity index (PDI), viscosity and pH of nanoemulsions were investigated. The results of the modeling showed that the experimental data could be adequately adapted in a second-order polynomial model with a multiple regression coefficient r2 of 0.821 for the prediction of particle size, PDI and viscosity. The long-term and thermodynamic stability of the prepared nanoemulsions were tested. The droplet size and morphology of the nanoemulsions were measured by dynamic light scattering (DLS) and transmission electron microscopy (TEM). On this basis, a water-insoluble insecticide diazinon was incorporated into 26 optimized nanoemulsion systems to demonstrate potential applications in pest control. The results of DLS and TEM measurements showed that most of prepared nanoemulsions had an almost monodisperse droplet size distribution (PDI < 200 nm). Incorporation of diazinon had no significant effect on the size and stability of the nanoemulsions and the formulated nanoemulsion remained stable after four months of storage. [ABSTRACT FROM AUTHOR]