Academic literature on the topic 'W/o emulsion'
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Journal articles on the topic "W/o emulsion"
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Ponphaiboon, Juthaporn, Sontaya Limmatvapirat, and Chutima Limmatvapirat. "Influence of Emulsifiers on Physical Properties of Oil/Water Emulsions Containing Ostrich Oil." Key Engineering Materials 777 (August 2018): 592–96. http://dx.doi.org/10.4028/www.scientific.net/kem.777.592.
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The fabrication of oil/water (O/W) emulsions in order to prepare the spray-dried encapsulated bioactive ostrich oil emulsions can be useful for increasing stability of commercial products. In this study, O/W emulsions were stabilized with mixed emulsifiers (Span and Tween) or soy lecithin. The effects of emulsifiers on the physical properties of emulsions containing ostrich oil were investigated. Results showed that the addition of a mixture of Span and Tween emulsifiers at concentrations between 5 and 15% w/w reduced the droplet size of the emulsions but did not decrease the zeta potential in the emulsion system. The smallest droplet size of 5.01±0.43 μm was obtained from the emulsion containing 15% w/w mixture of Span 20 and Tween 80. The zeta potential values of all emulsions containing a mixture of Span and Tween emulsifiers in the concentration range of 5 to 20% w/w were between-23 and-55 mV. In addition, the viscosity of these emulsions increased with increases in the concentrations of both emulsifiers. The stable 20% w/w ostrich oil emulsion stabilized with 15% w/w Span 20/Tween 80 presented viscosity equal to 69.56±1.82 cP. For 10% w/w ostrich oil emulsions stabilized with lecithin, the droplet size and zeta potential of the emulsions tended to decrease with increasing lecithin concentrations. An emulsion containing 10% w/w lecithin exhibited the smallest droplet size (3.93±0.11 μm). The zeta potential values of all emulsions composed of 1-15% w/w lecithin were between-33 and –66 mV and the viscosity of these emulsions increased with increases in the concentrations of lecithin. The stable 10% w/w ostrich oil emulsion stabilized with 10% w/w lecithin exhibited a high viscosity of 172.50±1.01cP. In summary, 10% w/w lecithin provides better emulsion stability than 15% w/w Span 20/Tween 80. These results therefore reveal important parameters for the fabrication of stable O/W emulsions containing ostrich oil.
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Bains, Upinder, and Rajinder Pal. "Rheology and Catastrophic Phase Inversion of Emulsions in the Presence of Starch Nanoparticles." ChemEngineering 4, no. 4 (2020): 57. http://dx.doi.org/10.3390/chemengineering4040057.
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Emulsions stabilized by solid nanoparticles, referred to as Pickering emulsions, are becoming increasingly important in applications as they are free of surfactants. However, the bulk properties and stability of Pickering emulsions are far from being well understood. In this work, the rheological behavior and catastrophic phase inversion of emulsions in the presence of starch nanoparticles were studied using in-situ measurements of viscosity and electrical conductivity. The aqueous phase consisting of starch nanoparticles was added sequentially in increments of 5% vol. to the oil phase under agitation condition to prepare the emulsions. The emulsions were water-in-oil (W/O) type at low to moderate concentrations of aqueous phase. At a certain critical volume fraction of aqueous phase, catastrophic phase inversion of W/O emulsion to oil-in-water (O/W) emulsion took place accompanied a sharp jump in the electrical conductivity and a sharp drop in the emulsion viscosity. The W/O emulsions were nearly Newtonian at low concentrations of aqueous phase. At high concentrations of aqueous phase, prior to phase inversion, the W/O emulsions exhibited a shear-thickening behavior. The O/W emulsions produced after phase inversion were shear-thinning in nature. The comparison of the experimental viscosity data with the predictions of emulsion viscosity model revealed only partial coverage of droplet surfaces with nanoparticles. With the increase in the concentration of starch nanoparticles (SNPs) in the aqueous phase of the emulsions, the phase inversion of W/O emulsion to O/W emulsion was delayed to higher volume fraction of aqueous phase. Thus SNPs imparted some stability to W/O emulsions against coalescence and phase inversion.
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Adeyi, Oladayo, Daniel Imwansi Ogiem Ikhu-Omoregbe, and Victoria A. Jideani. "Rheological Properties of Sunflower Oil-in-Water Emulsion Containing Vinegar, Stabilized with Gelatinized Bambara Groundnut Flour." International Journal of Engineering Research in Africa 36 (June 2018): 85–97. http://dx.doi.org/10.4028/www.scientific.net/jera.36.85.
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The influence of vinegar concentrations on the rheological properties of 40% (w/w) sunflower oil-in-water emulsions stabilized with 7% (w/w) gelatinized bambara groundnut flour (BGNF) was investigated. The rheological properties of interest were steady shear, time dependent and viscoelastic characteristics. Rheological characterizations of the emulsions were carried out using a shear rate controlled rheometer. Both emulsions with and without vinegar were pseudoplastic, thixotropic and viscoelastic fluids. Vinegar however, significantly (p < 0.05) affected rheological properties of BGNF-stabilized emulsion. Presence of vinegar in the emulsion decreased extent of thixotropy, pseudoplasticity and viscoelasticity of BGNF-stabilized emulsions. The results indicated that the rheological properties of BGNF-stabilized emulsion can be controlled and manipulated using vinegar however, the presence of vinegar in BGNF-stabilized emulsion may be deleterious to the emulsion. The result provided the information to understand the influence of vinegar on the rheological properties of BGNF-stabilized emulsions for product and process development.
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Tangirala, A. D. Srikanth, Prakyath S, Karthimol A, Sunil C.K., Ranjaragan J, and Rawson A. "Development and characterization of water-in-water emulsion using pea protein and different gums." Journal of Applied and Natural Science 17, no. 1 (2025): 78–86. https://doi.org/10.31018/jans.v17i1.6153.
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Water-in-water (W/W) emulsions are gaining attention for their potential applications in food and nutrition due to their unique properties, including biocompatibility and stability. However, achieving stable W/W emulsions remains challenging, requiring a careful combination of biopolymers. The present study aimed to formulate W/W emulsion using a combination of protein and polysaccharide phases. Pea protein (P) was considered for the protein phase, and locust bean gum (LBG), guar gum (GG), xanthan gum (XG) were considered for the polysaccharide phase. The protein-polysaccharide phases were mixed in 10:90, 20:80, 80:20, and 90:10 ratios to create nine W/W emulsion combinations for Pea protein-Locust bean gum (PL), Pea protein-Guar gum (PG), and Pea protein-Xanthan gum (PX) each. These 27 emulsion combinations were then characterized based on their particle size, interfacial tension, phase separation, microstructure, and rheological properties. PL-6 (60:40 ratio) exhibited the smallest particle size (0.1891 ± 0.0113 μm), lowest interfacial tensions (1.78 ± 0.071 mN/m), and superior rheological properties. The emulsion phase separation study showed that the process followed the Exponential decay model, with PL-6 having the lowest decay rate constants (k = 17.640 s⁻¹). The microstructure of the emulsions was revealed through Confocal laser scanning microscopy analysis. The results concluded that PL-6 emulsion proved highly effective for formulating a stable W/W emulsion. This research opens new possibilities for using such emulsions in various applications, particularly in food and nutritional security.
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Liu, Fei, Yongfei Li, Xiaqing Li, and Xuewu Wang. "Study on the Properties Changes of Reversible Invert Emulsion during the Process from O/W to W/O with Alkali." Molecules 29, no. 1 (2023): 62. http://dx.doi.org/10.3390/molecules29010062.
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The reversible emulsion drilling fluid system combines the advantages of both oil-based and water-based drilling fluids, which can achieve ideal results in different stages of drilling and completion, and the system can be reused to effectively reduce costs. However, the research on reversible emulsions mainly focuses on the development of new reversible emulsifiers, while the specific phase transformation mechanism of reversible emulsion systems is still unclear. In this paper, a stable reversible emulsion was prepared using the reversible emulsifier DMOB as a raw material, and the reversible emulsion performance of the alkali response from the O/W emulsion phase to the W/O emulsion was studied. The microstructure of reversible emulsions was studied by a microscope, a cryogenic transmission electron microscopy, and a laser particle size analyzer. The changes in macroscopic properties of reversible emulsions in the process of alkali conversion were studied by pH, conductivity, demulsification voltage, static stability, viscosity, rheology, and other indicators, and the conversion mechanism of reversible emulsions from O/W emulsion ⟶ bicontinuous structure ⟶ O/W/O emulsion ⟶ W/O emulsion was clarified. The details are as follows: in the first stage, when the amount of NaOH ≤ 0.43 vol.%, the overall particle size of the emulsion decreases first and then increases with the increase in NaOH dosage. In the second stage, when the amount of NaOH was 0.45 vol.%, a double continuous structure was formed inside the emulsion. In the third stage, when the amount of NaOH is 0.48 vol.%, the O/W/O emulsion is formed, and with the increase in stirring time, the internal oil droplets gradually accumulate and are discharged from the water droplets, and finally, the W/O emulsion is formed. In the fourth stage, when the dosage of 0.50 vol.% ≤ NaOH ≤ 5.00 vol.%, the W/O emulsion was formed, and with the increase of NaOH dosage, the structure and compactness between water droplets increased first and then decreased. In the whole process, with the increase in the amount of NaOH solution, the total particle size of the emulsion first decreased and then increased.
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Nguyen, Thuy Chinh, and Hoang Thai. "Review: emulsion techniques for producing polymer based drug delivery systems." Vietnam Journal of Science and Technology 61, no. 1 (2023): 1–26. http://dx.doi.org/10.15625/2525-2518/17666.
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Emulsification method is one of the popular methods for producing materials used inbiosensing, bioimaging and others, especially, drug delivery polymer systems in microsize andnanosize. The concrete techniques related to this method are emulsification, self-emulsification,in a combination with solvent evaporation process, homogenization, or ultranosication. Thestructure of emulsion formulation consists of two phases: an internal phase and an externalphase. Based on the structure and nature of the phases, emulsions can be classified into differenttypes such as two-phase systems (oil in water emulsion (O/W) or water in oil emulsion (W/O))or three-phase systems (water in oil in water triple emulsion (W/O/W) or oil in water in oil tripleemulsion (O/W/O)). The droplet sizes in micro-emulsion systems are often higher than 1 mwhile those in nano-emulsions or mini-emulsions are in the range of 100-500 nm. Some specialnano-emulsion systems can contain droplets with a size of few nanometers. Factors includingsolvents, oil/water phase ratio, droplet oil size, composition ratio, nature of raw materials,emulsifiers, etc. can affect the morphology, properties, and size of the obtained products. Thispaper reviews emulsion techniques which have been applied for producing polymeric drugdelivery systems. The components, properties, characteristics, encapsulation efficiency as wellas drug release rate, water solubility, toxicity and administration efficacy of drug emulsionformulations will be mentioned. Advantages and limitations of emulsion techniques are alsodiscussed.
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N. H. Abdurahman and H. A. Magdib. "Surfactant (UMP) for emulsification and stabilization of water-in-crude oil emulsions (W/O)." Maejo International Journal of Energy and Environmental Communication 2, no. 2 (2020): 18–21. http://dx.doi.org/10.54279/mijeec.v2i2.245027.
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The purpose of this research is to look into the formulation and evaluation of concentrated water-in-oil (W/O) emulsions stabilized by UMP NS-19-02 surfactant and their application for crude oil emulsion stabilization using gummy Malaysian crude oil. A two-petroleum oil from Malaysia oil refinery, i.e., Tapis petroleum oil and Tapis- Mesilla blend, were utilized to make water-in-oil emulsions. The various factors influencing emulsion characteristics and stability were evaluated. It was discovered that the stability of the water-in-oil emulsion improved by UMP NS-19-02 improved as the surfactant content rises, resulting in the decline of the crude oil-water interfacial tension (IFT). Nevertheless, the most optimum formulation of W/O emulsion was a 50:50 W/O ratio with 1.0% surfactant. Additionally, raising the oil content, salt concentration, duration and mixing speed, and pH of the emulsion resulted in higher emulsion stability. It also raised the temperature of the initial mixing, which significantly decreased the formulated emulsions' viscosity. The results showed that stable emulsions could be formed using the UMP NS-19-02 surfactant.
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Kim, Do-Yeong, and Hyunsu Kim. "Effect of Mucilage Extracted from Corchorus olitorius Leaves on Bovine Serum Albumin (BSA)-Stabilized Oil-in-Water Emulsions." Polymers 15, no. 1 (2022): 113. http://dx.doi.org/10.3390/polym15010113.
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The present study examined the effect of mucilage extracted from Corchorus olitorius L. leaves on the emulsifying stability of bovine serum albumin (BSA)-stabilized oil-in-water (O/W) emulsions during the storage for seven days. O/W emulsions were prepared with a 90% aqueous phase containing C. olitorius mucilage (0–1.00% w/v) together with 0.5% (w/v) BSA and 10% oil phase. Emulsion properties were analyzed by measuring droplet size, zeta potential, spectroturbidity, backscattering profiles (%BS), and visual observations. The mean droplet size of emulsions prepared with 0.75 and 1.00% mucilage did not show significant changes during storage. The zeta potential of all the emulsions exhibited a negative charge of approximately −40 mV, but electrical repulsion was not the dominant stabilization mechanism in the emulsion. C. olitorius mucilage was able to increase the viscosity of the aqueous phase of the O/W emulsion system, which prevented droplet flocculation and enhanced the emulsion stability against phase separation at higher concentrations. The most stable emulsions during the storage period were those with 1.00% C. olitorius mucilage. In conclusion, C. olitorius mucilage has good potential for the preparation of stable O/W emulsions and can be used as a plant-based natural emulsifying and thickening agent in the food industry.
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Opustilová, Kristýna, Barbora Lapčíková, Daniela Sumczynski, and Richard Adámek. "Preparing O/W/O Emulsion for Curcumin (Curcuma longa) Delivery and In Vitro Digestibility Assay." International Journal of Molecular Sciences 26, no. 12 (2025): 5639. https://doi.org/10.3390/ijms26125639.
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In this study, simple oil-in-water emulsions (O/W) and multiple O/W/O emulsions were employed as carriers for a curcumin delivery system. The stability of emulsions was evaluated using DSC (differential scanning calorimetry), accompanied by particle size measurement by DLS (dynamic light scattering) and rheological analysis. The amount of freezable water (Wfs) in O/W emulsion was determined to be 80.4%, while that in O/W/O emulsion was 23.7%. Multiple emulsions had a more complex structure than simple emulsions, being characterized by higher stability with predominant loss modulus over storage modulus (G” > G’). The mean surface diameter for O/W emulsion was 198.7 ± 9.8 nm, being approximately two times lower than that for multiple emulsions. Curcumin in vitro digestibility was observed for both emulsions and, additionally, the digestibility of fresh and dried curcuma root powders was investigated. Multiple emulsions were found to be a superior matrix for curcumin delivery, with higher stability and emulsion digestibility of 50.6% for the stomach and small intestine. In vitro digestion of dried curcuma powders and curcuma root samples was monitored by HPLC (high-performance liquid chromatography). The DMD (dry matter digestibility) for dried curcuma powders ranged between 52.9% to 78.8%, and for fresh curcuma (KF) was 95.5%.
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Li, Yichen, Jiaqi Ding, Yaxin Wu, et al. "Construction of a Yeast Protein-Chitooligosaccharide W/O/W Emulsion System for Carrying and Stabilization of Betacyanins." Foods 14, no. 8 (2025): 1337. https://doi.org/10.3390/foods14081337.
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Natural pigments like betacyanins are highly unstable under heat, light, acid, and alkaline conditions. Yeast protein (YP) is a promising substitute protein, while chitooligosaccharides (COS) are water-soluble alkaline polysaccharides. Water-in-oil-in-water (W1/O/W2) emulsions, with two-membrane, three-phase structure, can serve as effective carriers for stabilizing pigments. In this study, YP-COS complexes formed through electrostatic interactions were used as hydrophilic emulsifiers to create betacyanin-coated W1/O/W2 emulsions. The W1/O colostrum was designed to make up 30%, 70%, and 90% of the emulsion (v/v)and the W2 was designed by the complexes with three concentrations of YP (2%, 1.25% and 0.5%, w/v)-COS (6%, 3.75% and 1.5%, w/v). The optimal formulation was determined through comprehensive evaluation of micromorphological characteristics, particle size, zeta potential and creaming index, ultimately yielding a system comprising YP (2%)-COS (6%) and 90% W1/O colostrum. Moreover, the W1/O/W2 emulsion system significantly improved the betacyanins retention under thermal treatment, photolytic exposure, pH gradients, and extended storage compared to the betacyanin aqueous solution (p < 0.05). In vitro digestion tests showed the emulsion retained 58.39% of betacyanins, while the betacyanin aqueous solution retained only 41.42%, demonstrating the emulsion’s ability to delay the betacyanins release, offering new insights for using YP-COS complexes in food production and other fields.
Dissertations / Theses on the topic "W/o emulsion"
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Pu, Xiaolu. "Impact of hydrophilic emulsifier and emulsion microstructure on aroma release over w/o/w emulsions." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52014/.
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In this thesis, the impact of the interactions between the hydrophilic emulsifiers and aroma compounds as well as emulsion microstructure including droplet size, droplet size distribution, emulsion stability and creaming on aroma release over water-in-oil-in-water (w/o/w) emulsions was investigated. Polyglycerol polyricinoleate (PGPR) was used as the only hydrophobic emulsifier to stabilise the internal water droplets in the primary water-in-oil (w/o) emulsion of the w/o/w emulsions throughout this research. Three hydrophilic emulsifiers investigated to stabilise the w/o droplets in w/o/w emulsions included a low molecular weight non-ionic surfactant, polyoxyethylene 20 sorbitan monolaurate (Tween 20), a chemically modified starch, octenyl succinic anhydride (OSA) starch and a protein, pea protein isolate (PPI), as the large molecular weight emulsifiers. The two emulsification methods of high shear mixing and stirred cell membrane emulsification were used. Controls of water and oil-in-water (o/w) emulsions were prepared with the formulation and process conditions as for the w/o/w emulsions. Emulsion microstructure was characterised in terms of droplet appearance, droplet size, droplet size distribution as well as emulsion stability over time. Both static and dynamic headspace analyses were carried out to investigate the aroma release behaviour over w/o/w emulsions. The results showed that w/o/w emulsions were a suitable vehicle for short time aroma entrapment, which was most successful for the hydrophilic aroma acetoin compared to the hydrophobic aromas acetyl pyridine and hexanal. This entrapment of the hydrophilic aroma resulted from the barrier of the oil phase in the w/o droplets to delay its diffusion or the PGPR micelles in the oil phase to entrap it in the polar inner core. The complex food emulsifiers OSA starch and PPI were for the first time successfully used in stirred cell membrane emulsification to produce similarly sized o/w and w/o/w emulsions. These were produced to eliminate the effect of droplet size in the study of aroma release. The release of aromas (i.e. diacetyl and 3-pentanone) was affected by the combination of the type of the hydrophilic emulsifier (Tween 20, OSA starch and PPI) and the type of the emulsion system (i.e. o/w and w/o/w emulsions) as well as the emulsion microstructure including droplet size, emulsion stability, interface thickness, creaming and diffusion of the internal water phase into the external water phase of w/o/w emulsions. The thinner interface laden by Tween 20 might lead to a quicker diffusion of the hydrophobic aroma 3-pentanone from the w/o droplets into w2. OSA starch interacted with the hydrophilic aroma diacetyl and 3-pentanone, and PPI interacted with 3-pentanone. These findings help to better understand the effect of the hydrophilic emulsifier and emulsion microstructure on aroma release and present a novel study to produce similarly sized emulsion droplets with complex food emulsifiers.
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Sharma, Anita. "Water-in Water (W/W) Emulsion Drug Delivery Systems." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1365954454.
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Rillmann, Thomas. "Untersuchungen an einfachen W-, O-Modellsystemen." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=959822259.
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Kennelly, Timothy Robert. "An investigation of the combustion of oil sand derived bitumen-in-water emulsions." Thesis, University of Iowa, 2009. https://ir.uiowa.edu/etd/246.
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Dwindling conventional oil resources has caused exploration efforts to focus elsewhere. Bitumen from oil sands has emerged as one of the primary unconventional oil resources in use today. Quadrise Canada Corporation has harnessed this unconventional oil by developing their bitumen-in-water emulsion known as MSAR (Multi-Phase Superfine Atomized Residue). Fuel-in-water emulsions are linked to a combustion phenomenon known as micro-explosion, which are associated with an increase in combustion efficiency and decrease in harmful emissions. A study has been conducted of the MSAR fuel to help advance the optimization and modeling of its use in spray combustors so as to best harness the potential. Quantitative and qualitative data has been obtained during combustion experiments of the fuel that will attribute to this end. Additionally, a simplified statistical model is presented based on the governing equations to describe the atomization that occur as a result of micro-explosions of the MSAR fuel as well as a simple model to represent internal force needed for a micro-explosion to occur. The results of this study continue to reinforce the understanding that micro-explosions cannot be attributed to one overriding physical principal, but rather are th result from variations in turbulent, dynamic, and thermal forces.
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Melzer, Eva. "Herstellung und physikochemische Charakterisierung von W-O-Emulsionen unter Verwendung von Ethylcellulose als nichtionischem Polymeremulgator." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=959954481.
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Miyagawa, Yayoi. "Analysis of factors affecting dispersion stability of O/W emulsion during freezing and thawing processes." Kyoto University, 2018. http://hdl.handle.net/2433/232339.
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Wardhono, Endarto Yudo. "Optimization of concentrated W/O emulsions : stability, trapping and release of polysaccharides." Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP1814/document.
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Cette étude s'inscrit dans le cadre du projet Européen VEGEPHY (VEGEtale-PHYtosanitaire) dont le but est de développer un produit support destiné à être pulvérisé pour protéger les plantes des viroses. Le produit étudié est une émulsion de type eau-dans-huile (E/H) à base d’une solution aqueuse de polysaccharide et d’esterméthylique de colza comme phase continue. Le polysaccharide est utilisé sous forme d'adjuvant afin de modifier les propriétés rhéologiques de la préparation phytosanitaire (bouillie) et ainsi de limiter la dérive des gouttelettes lors de la pulvérisation. Le but est également d’améliorer le contact des gouttes sur le végétal traité. L'objectif de ce travail est de formuler une émulsion (E/H) avec une concentration maximale de polysaccharide, qui soit stable sur le long terme (environ 2 ans) et d'étudier, lors de la mise en œuvre du produit, les mécanismes de relargage dans un laps de temps efficace devant rester inférieur à 600 s. Les émulsions (E/H) concentrées ont été réalisées à l'aide d'un système rotor stator à température ambiante. La phase aqueuse contenant le polysaccharide et du glycérol a été dispersée dans une phase huileuse agitée dans laquelle un surfactant (lécithine ou PolyRicinoléate de PolyGlycérol, PGPR) a préalablement été dissous. Des tests de stabilité ont été menés immédiatement après les phases de préparation ou par un vieillissement accéléré. Différents paramètres qui ont une influence sur cette stabilité ont été étudiés par DSC, observations microscopiques, diffraction laser et mesure des propriétés rhéologiques. Les analyses DSC ont été utilisées poursuivre l'évolution de la taille des gouttes en fonction du temps. En effet, le comportement thermique des émulsions pendant les phases de congélation et de fusion permet de calculer la fraction d’eau congelée dans les gouttelettes et sa mise en relation avec l’évolution de la stabilité des émulsions. Le relargage du polysaccharide (CarboxyMethylCellulose, CMC) est obtenu en deux étapes : déstabilisation de l'émulsion primaire E/H par un produit chimique puis dilution dans l'eau pour obtenir une émulsion (H/E) avec la concentration désirée de polysaccharide dans la phase aqueuse. La déstabilisation a été étudiée en observant l'évolution des gouttelettes par DSC. Le procédé de dilution a été étudié par une mesure de la conductivité de la solution aqueuse couplée à un modèle cinétique de relargage du CMC.La formulation et la stabilité de l'émulsion (E/H) ont montré que la DSC, complétée par d'autres techniques, est une méthode appropriée pour déterminer les caractéristiques des émulsions. L'étude du comportement lors de la congélation montre que la proportion de glace formée dans les gouttelettes durant les tests DSC est en bonne adéquation avec les mesures DSC et les calculs thermodynamiques. L'utilisation du PGPR comme tensioactif et l'ajout du glycérol dans la formulation permettent d'augmenter la stabilité de l'émulsion à long terme. La formulation optimum obtenue contient 3.5 % (m/m) de CMC, 10 % (m/m) de glycérol dans 75 % (v/v) de phase dispersée et 14 % (m/m) de PRPG dans la phase continue. Un modèle empirique peut être utilisé pour décrire la cinétique de relargage. Pour déstabiliser l'émulsion (E/H), la quantité optimum de tensioactif anionique Cynthiorex PMH1125 est de 10 % (m/m) dans première émulsion avec NRe ≥ 4200 et T ≥ 20°C. Dans les conditions réelles d’utilisation de la préparation au champ, le temps minimum de relargage est d'environ 200 secondes<br>This study is a part of the European project VEGEPHY (VEGEtale-PHYtosanitaire) to develop a product for the crop protection purposes. The product is a concentrated W/O emulsion trapping of a polysaccharide in the aqueous phase and rapeseed methyl ester oil as a continuous phase. Polysaccharide is used as a thickening adjuvant to modify the rheology properties of the water-based spray solution in order to reduce the drift of thespray. The objective of this study is to formulate concentrated W/O emulsions incorporation with the maximum amount of polysaccharide which show long stability (for over 2 years) and to study the release mechanism of polysaccharide in suitable conditions with a goal of an efficiency time less than 600 seconds.Concentrated W/O emulsions were realized by using a rotor stator system at room temperature. Aqueous phase containing polysaccharide and glycerol was dispersed into the stirred oil continuous phase where in a surfactant (lecithin and/or polyglycerol polyricinoleate, PGPR) has been previously dissolved. Stability tests were performed immediately after preparation and after ageing tests. Various parameters having an influence on thestability have been interpreted from DSC thermogram parallel with microscopic observation, laser diffraction granulometry and rheology measurement. DSC technique was used to study the emulsions by following the evolution of the droplet size versus time. Thermal behaviour of emulsions may be evaluated when they under gofreezing and melting in which the proportion of ice formed in the droplets may be calculated and their link with the evolution of the emulsion versus time. The release of the polysaccharide (CarboxyMethyl Cellulose, CMC)from the emulsion system is obtained by a two steps process : destabilization of the primary W/O emulsion by achemical product and dilution in water that gives an O/W emulsion containing the required concentration of polysaccharide. Destabilization was observed by following the evolution of dispersed droplets using DSC. Dilution process was assessed by measuring electrical conductivity of the water solution and a mathematical model to represent the kinetic release of CMC in water was proposed.The formulation and the stability of concentrated W/O emulsion has shown that DSC completed with granulometry and rheometry is an appropriate technique to study the emulsion characteristics. The study offreezing behaviour of emulsions show that the proportion of ice formed in the dispersed droplets during DSC test indicates good agreement between DSC measurements and thermodynamics calculation. The use of PGPRas surfactant and the introduction of glycerol in the formulation are beneficial to improve the long‐term stabilityof the emulsion. The optimum formulation of concentrated W/O emulsion was obtained containing : 3.5% w/wof CMC, 10% w/w of glycerol in 75% v/v of dispersed phase and 14% w/w of PGPR in the continuous phase. From the release study, an empirical model may be used to describe the released kinetic. The optimum amount of nonionic surfactant Cynthiorex PMH 1125 to break primary W/O emulsion was found at 10% w/w in the primary emulsion with NRe ≥ 4200 and T ≥ 20°C. Under practical field conditions, the minimum release time isthen around 200 seconds
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Nkomo, Sithethi Espin. "Using rheometry for prediction the pumping characteristics of highly concentrated W/O emulsion explosives." Thesis, Cape Peninsula University of Technology, 2005. http://hdl.handle.net/20.500.11838/912.
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Dissertation submitted in fulfilment of the requirements for the Masters Degree in
Technology: Chemical Engineering in the Department of Chemical Engineering of
Cape Peninsula University ofTechnology, 2005<br>The emulsion used for this study is a new thermodynamically unstable multi-component waterin-
oil (w/o) explosive type with an internal phase ratio of approximately 94%, i.e. far beyond the
close packing limit of spherical droplets of 74%. Economic considerations and the ongoing need
for continuous drilling, loading and blasting in the mining industry, has made long-distance
pipeline transportation of these emulsion explosive systems a viable economic option. Presently,
rheological characterization of emulsion explosives is well documented (Bampfield & Cooper,
1988, Utracki, 1980). However, very little or none has been done for this system, pertaining to
the use of rheometry for prediction of pumping characteristics of these systems in long-distance
pipeline transport. This Master's dissertation is devoted to develop rheological methods of
testing, characterization and correlation in order to develop a basis for predicting the pumping
characteristics of highly concentrated w/o emulsion explosives from rheometry.
The literature and theory pertinent to the pipeline flow of high internal phase ratio emulsion
explosives are presented, as well as the fundamentals of both concentric cylinder rheometry and
pipe viscometry. The most relevant is the work of Bampfield and Cooper (1988), Utracki (1980)
and Pal (1990).
Two experimental test facilities were used for data collection. Pipeline experiments were done
using an experimental test facility at African Explosives Limited (AEL), and rheometry was
conducted at the Rheology Laboratory of the Cape Peninsula University of Technology Flow
Process Research Centre. The AEL experimental test facility consisted of a four-stage Orbit
progressive cavity pump, two fluid reservoirs, (a mixing tank and a discharge reservoir), five 45m
HOPE (high density polyethylene) pipes of internal diameters of 35.9 mm, 48.1 mm, 55.9 mm,
65.9 mm and 77.6 mm pipes. The test work was done over a wide range of laminar flow rates
ranging from 3 kg.min-I to 53 kg.min-I
. Rheometry was done using a PaarPhysica MCR300
rheometer, and only standard rotational tests (i.e. flow curve) at 30 °c in controlled rate mode
were done.
Rheological characterisation was done using three rheological models, i.e. the Herschel-Bulkley,
the Power Law and the Simplified Cross models. The coefficients obtained from these models
were then used to predict pumping characteristics. The performances of these models were then
evaluated by comparing the pipeline flow prediction to the actual pipeline data obtained from
pipeline test experiments. It was found that the flow behaviour depicted by this explosive
emulsion system was strongly non-Newtonian, and was characterized by two distinct regions of
deformation behaviour, a lower Newtonian region of deformation behaviour in the shear rate
region lower than 0.001 S-I and a strong shear thinning region in the shear rate range greater than
0.001 S-l.
For all the models used for this study, it was evident that rheometry predicts the pumping
characteristics of this high internal phase ratio emulsion reasonably well, irrespective of the
choice of the model used for the predictions. It was also seen that the major difference between
these models was in the lower shear rate domain. However, the Simplified Cross model was
preferred over the other two models, since its parameter (the zero shear viscosity denoted by 110)
can in general be correlated to the structure of the emulsion systems (i.e. mean droplet size, bulk
modulus, etc.). Thus, structural changes induced by shearing (either inside the pump or when
flowing inside a pipe) can be detected from changes in the value of the 110. The above statement
implies that Tlo can be used as a quality control measure. Different pumping speeds were found to
cause different degrees of shear-induced structural changes which were manifested by two
opposing processes. These two opposing processes were the simultaneous coalescence and
flocculation of droplets encountered at low rates of shear, and the simultaneous refinement and
deflocculation of droplets encountered at high rates of shear. These two droplet phenomena were
associated with a decrease or an increase in viscous effects, leading to both lower and higher
viscous stresses and pumping pressures during pump start-up respectively.
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Ma, Tiezheng. "Oxidation Kinetics of Methyl Linoleate and α-Linolenate in Bulk and Oil-in-water Emulsion Systems". Kyoto University, 2014. http://hdl.handle.net/2433/188751.
Full textAbstract:
Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(農学)<br>甲第18313号<br>農博第2038号<br>新制||農||1020(附属図書館)<br>学位論文||H26||N4820(農学部図書室)<br>31171<br>京都大学大学院農学研究科食品生物科学専攻<br>(主査)教授 安達 修二, 教授 河田 照雄, 教授 保川 清<br>学位規則第4条第1項該当
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Friedrich, Sybille. "Dielektrische und rheologische Untersuchungen an konzentrierten kosmetischen W/O-Emulsionen : Möglichkeiten der Emulsionscharakterisierung /." [S.l. : s.n.], 2002. http://www.gbv.de/dms/bs/toc/362353581.pdf.
Full textBooks on the topic "W/o emulsion"
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Hauth, Ariane. O/W-Emulsionen schädigen die Hornschichtbarriere und verbessern die Wirkstoffpenetration. 2003.
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Harnisch, Stephan. Vergleichende Untersuchungen zur Plasmaproteinadsorption auf O/W-Emulsionen und Polymer-Partikeln zur parenteralen Anwendung. 1998.
Find full textBook chapters on the topic "W/o emulsion"
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Bährle-Rapp, Marina. "W/O-Emulsion." In Springer Lexikon Kosmetik und Körperpflege. Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_11211.
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Bährle-Rapp, Marina. "O/W-Emulsion." In Springer Lexikon Kosmetik und Körperpflege. Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_7296.
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Bährle-Rapp, Marina. "O/W/O-Emulsion." In Springer Lexikon Kosmetik und Körperpflege. Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_7297.
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Calderó, Gabriela, and Conxita Solans. "Polymeric O/W Nano-Emulsions Obtained by the Phase Inversion Composition (PIC) Method for Biomedical Nanoparticle Preparation." In Emulsion Formation and Stability. Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527647941.ch7.
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Ritthidej, G. C., W. Pichayakorn, C. Kusonwiriyawong, and V. Lipipun. "Preparation of Chitosan Nanoparticles for Protein Delivery by w/o/w Emulsion Solvent Evaporation and Simple Ionotropic Gelation Techniques." In Solid State Phenomena. Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/3-908451-30-2.751.
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Supsakulchai, Anchali, Guang-Hui Ma, Masatoshi Nagai, and Shinzo Omi. "Microencapsulation of Fine Titanium Dioxide Powders from (S/O)/W Emulsion with Subsequent Solvent Evaporation." In ACS Symposium Series. American Chemical Society, 2001. http://dx.doi.org/10.1021/bk-2002-0801.ch018.
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Tanthapanichakoon, W., N. Sowasod, and T. Charinpanitkul. "Development of Nanoencapsulated Curcumin in Chitosan for Cosmetic Use via Evaporation of O/W/O Emulsion." In Ceramic Transactions Series. John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118144145.ch29.
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Bährle-Rapp, Marina. "W/O/W-Emulsionen." In Springer Lexikon Kosmetik und Körperpflege. Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_11220.
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Li, Huan, Xiaolin Wang, Sifang Hou, Wei Jiang, Xin Peng, and Yangying Si. "Study on the Stability of W/O Emulsions Based on Droplet Size Distributions and Microstructures—Taking the Shale Oil Emulsion in Changqing Oilfield as an Example." In Springer Series in Geomechanics and Geoengineering. Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-96-5158-0_3.
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Kamarudin, Khairul Sozana Nor, and Inamullah Bhatti. "Preparation and Characterization of W/O Emulsion Liquid Membrane Containing Diethanolamine (DEA) for Carbon Dioxide Separation from Gas Mixtures." In Sustainable Membrane Technology for Energy, Water, and Environment. John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118190180.ch18.
Full textConference papers on the topic "W/o emulsion"
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Keogh, William, Gifty Oppong Boakye, Anne Neville, et al. "Lead Sulfide (PbS) Scale Behavior and Deposition as a Function of Polymeric Sulfide Inhibitor Concentration in Multiphase." In CORROSION 2018. NACE International, 2018. https://doi.org/10.5006/c2018-10972.
Full textAbstract:
Abstract Deposition of inorganic mineral scale on downhole completion equipment contributes to significant downtime and loss of production within the oil and gas industry. High temperature/high pressure (HT/HP) fields have reported build-up of lead sulfide (PbS) scale as a consequence of reservoir souring; and the resultant reaction between dissociated sulfide anions from hydrogen sulfide (H2S) and heavy metal cations. In this work, laboratory apparatus enabled simulation of scale precipitation under turbulent emulsion-forming multiphase conditions, with behavior of PbS particles at the oil/water interface and subsequent adhesion onto anti-fouling surfaces measured at a range of polymer concentrations. Introduction of polymer sulfide inhibitor (PSI) product to the formation brine at concentrations of 500mg/L reduced overall PbS deposition whilst addition of 5000mg/L further reduced scale crystallisation but resulted in complete emulsification of the light oil phase. The tendency of soluble polymers to act as surfactants led to increased stabilisation of the formed oil in water (o/w) emulsion with heightened PSI concentration. Optical microscope, gravimetric and rheological measurements explained depositional behaviour; whereby enhanced o/w emulsion viscosity and stability due to amphiphilic polymer adsorption onto both PbS scale and oil droplet interfaces resulted in uniform deposition upon all surfaces.
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Liu, Yanchi, Guodong Wu, Erdong Yao, et al. "Research on Influencing Factors of Heavy Oil Emulsification." In ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/omae2021-62820.
Full textAbstract:
Abstract In tight heavy oil reservoirs, the formation of W/O emulsion will significantly increase the viscosity of the whole fluid-system. Meanwhile, the emulsion droplets tend to block the core pores, which will reduce the flow oil and water. In this paper, the terms of oil-water ratio, pH and other factors on heavy oil emulsification of tight sandstone in a block of Xinjiang were studied. Furthermore, in order to study the emulsification behavior in large and small pores, a large tube and a small tube are used to investigate how the hole apertures affect heavy oil emulsification. Finally, the demulsification time and dehydration rate were recorded, and the interfacial tension and viscosity were tested. The results show that heavy oil is easy to self-emulsify with water to form W/O emulsion, and it’s extremely stable. When the oil-water ratio is 3:7, the viscosity of the emulsions reaches 307 mPa·s, which is 38 times higher than that of crude oil. Acidic and alkaline conditions are benefit of demulsification and the stability of the emulsions is reduced. In small tube with higher interfacial tension, the demulsification time is shortened, and the stability of the emulsions is reduced.
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Ma, Liran, Jianbin Luo, and Chenhui Zhang. "Behavior of O/W Emulsion Under Point Contact." In ASME/STLE 2012 International Joint Tribology Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ijtc2012-61091.
Full textAbstract:
Worldwide efforts to illuminate the behavior of multiple-phase liquid are frequently focused on oil-in-water emulsions. With the aim to reveal the machanism of the film formation of aqueouse emulsion in confinement, we observed the behavior of O/W confined in a nanogap. We have observed the oil pool formed surrounding the contact area in the inlet, derived from the oil film adhered on the solid surfaces, as well as the research into how the oil pool changes with rolling speed and feeding mode. Two regions have been found in the outlet area, which are defined as vaccum region and turn-round region. Small droplets have been observed to turn round in the turn-round region, with a diminishing droplet-size distribution. Moreover, by employing two different feeding modes, we have demonstrated a suprising discovery diametrically opposed to the traditional concept. The film formation has been detedcted to be distinctly enhanced under an insufficient feeding condition compared to the situation under a sufficient feeding condition. The unusual performance leads to an strong evidence of the reemulsification concept. Here, we demonstrate, directly from experimentally observations of emulsion behaivors, that the film formation of emulsion is significantly affected by the droplet behavior.
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Leask, Scott B., Vincent G. McDonell, and Scott Samuelsen. "Emulsion Jet in Crossflow Atomization Characteristics and Dynamics." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-75818.
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This work presents the atomization characteristics and dynamics of water-in-heptane (W/H) emulsions injected into a gaseous crossflow. W/H mixtures were tested while varying momentum flux ratios and aerodynamic Weber numbers. Different injector orifice diameters and orifice length-to-diameter ratios were used to test the generality of the results. The atomization properties of W/H mixtures were compared with properties of neat water and neat heptane to evaluate the effect of an emulsion on droplet sizing, cross-sectional stability and dispersion, and jet penetration depth. Liquid dynamics were extracted through analyzing instantaneous spray measurements and dynamic mode decomposition (DMD) on high-speed video recordings of the atomization processes. Correlations were proposed to establish preliminary relationships between fundamental spray processes and test conditions. These correlations allowed for emulsion behavior to be compared with neat liquid behavior. The use of emulsions induces greater spray instability than through using neat liquids, likely due to the difficulty in injecting a stable emulsion. Neat liquid correlations were produced and successfully predicted various spray measurements. These correlations, however, indicate that injector geometry has an effect on spray properties which need to be addressed independently. The emulsions are unable to adhere to the neat liquid correlations suggesting that an increased number of correlation terms are required to adequately predict emulsion behavior.
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Gallegos, C., M. C. Sánchez, A. Guerrero, and J. M. Franco. "Effect of Process Parameters on the Rheological Properties of O/W Emulsions." In ASME 1996 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/imece1996-0242.
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Abstract An overview of the effects that different processing conditions have on the rheology and droplet size distribution of o/w emulsions containing different macromolecular and low molecular weight emulsifiers is presented. The processing variables studied were emulsification time, agitation speed, temperature of emulsification, previous thermal treatment of the continuous phase and type of device used. Generally, an increase in the energy input during emulsification yields lower values of the mean droplet size, but does not always improve the viscoelastic properties of the emulsion. Thus, the bulk rheology of the emulsions may also be influenced by the phase behavior of the surfactant-water system, or by changes in the structural conformation of proteins. These influences are easily changed by modifying the temperature of emulsification or by a pre-emulsification thermal treatment of the continuous phase, which affect the microstructure of the emulsion and, subsequently, its linear viscoelastic behavior.
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Hattori, Tokima, Xingjuan Hao, Mai Shimokawara, Yoshitake Kato, Ryuta Kitamura, and Yogarajah Elakneswaran. "Influence of Inorganic Solid Particles in the Formation and Stability of Crude Oil Emulsion." In International Petroleum Technology Conference. IPTC, 2023. http://dx.doi.org/10.2523/iptc-22863-ea.
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Abstract Water-in-oil (W/O) emulsion could be formed during the transportation, refining, and storage of crude oils. In the stockpiling tanks, the emulsion and sludge formation were observed by storing of crude oils for a long period of time and cleaning of tanks. It has been reported that the presence of solids affects the emulsion types as well as the stability of emulsions produced. In addition, the surface properties of inorganic particles could influence the crude oil/water interface and thus affect the crude oil-water emulsion stability. Therefore, in this study, the presence of inorganic solid particles on the formation and stability of emulsion was quantitatively evaluated. A crude oil and synthetic brine were used for emulsion evaluation. In addition, calcite and kaolinite were selected as inorganic solid particles. Emulsions were prepared by mixing crude oil and synthetic brine at a ratio in volume of 1:9. The prepared emulsion was allowed to rest for 24 h and then centrifuged to separate crude oil and water. The volume and pH of resolved water were measured to assess emulsion stability in the presence of inorganic solids. It is found that the addition of inorganic solid particles increased the volume of resolved water and destabilize the emulsion compared to that of without inorganic solid particles. The concentration of solids influences the formation of stable emulsion: high concentration decreases the stable emulsion formation. The dissolution of inorganic solids increases the pH of the water and promotes the demulsification due to high surface potential of crude oil. Moreover, the solid particles enhance the formation of oil-in-water-in-oil (O/W/O) emulsion and thus generates unstable emulsion. Increase of temperature and addition of inorganic solids decrease the emulsion height, which was predicted by emulsion layer growth model where coagulation rate constant was a tuning parameter. High value of the coagulation rate constant implies strong coagulation between water droplets and facilitate emulsion instability.
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Pal, Rajinder. "Rheology and Stability of Emulsion Liquid Membranes." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-1180.
Full textAbstract:
Abstract The rheological properties of a series of oil-in-water-in-oil (O/W/O) and water-in-oil-in-water (W/O/W) types emulsion liquid membrane systems were measured using a controlled-stress rheometer. The effect of storage time (aging) on the rheological properties was also determined. The fresh O/W/O type emulsion liquid membranes exhibited a power-law non-Newtonian behaviour at high values of the primary emulsion concentration. Also, the viscosity increased with the increase in the total dispersed phase concentration. Upon aging, the viscosity of the O/W/O type emulsion liquid membrane decreased significantly. The photomicrographs indicated a decrease in the diameter of the multiple droplets due to expulsion of internal phase droplets to the external phase. The fresh W/O/W type emulsion liquid membrane (primary emulsion volume fraction of 0.692) exhibited a highly nonlinear behaviour. With the increase in the shear stress, the viscosity first decreased substantially. However, at some critical shear stress, a sharp increase in viscosity was observed indicating shear-thickening effect. The shear-thickening effect observed in W/O/W type systems was due to phase inversion; the W/O/W type emulsion liquid membrane system inverted to water-in-oil (W/O) emulsion at high shear stresses. Upon aging, the viscosity of the W/O/W type emulsion liquid membrane initially increased with an increase in storage time and then decreased with a further increase in storage time. The photomicrographs indicated swelling of dispersed droplets initially with the increase in storage time. The droplet size, however, decreased significantly with further increase in storage time. The changes in the rheological properties with aging are explained in terms of droplet size changes that occur during aging.
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Beldengrün, Yoran, Vanessa Dallaris, Clara Jaén, et al. "Preparation and Properties of Multiple Water-in-Water-in-Water (W/W/W) emulsion." In 14th Mediterranean Congress of Chemical Engineering (MeCCE14). Grupo Pacífico, 2020. http://dx.doi.org/10.48158/mecce-14.dg.02.07.
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Dayili, Mohammed, Alwaleed Alghamdi, Hala Sadeg, and Amr Abdel-Fattah. "Investigating Separation Efficiency of Oil-in-Water Emulsions Subjected to an Acoustic Field." In Middle East Oil, Gas and Geosciences Show. SPE, 2023. http://dx.doi.org/10.2118/213344-ms.
Full textAbstract:
Abstract The demand for improved technologies that enhance the separation of low concentrations of oil from water and thus reduce the increasing retention times in surface separation facilities is increasing. Acoustophoresis is a promising technique where acoustic direct radiation forces can aid to demulsify O/W emulsions and enhance oil separation of the produced water stream. Herein, we explored the coalescence behavior of oil-in-water emulsion in a stationary acoustophoretic setup. To quantify the acoustic O/W separation efficiency and identify the proper acoustic parameters for various O/W emulsion compositions, a series of experiments were conducted in large-scale (4-in × 4in × 12-in) acoustic resonator using O/W emulsions of different compositions. The separation efficiency is assessed by comparing the oil layer thickness of an emulsion separated by gravity alone with that separated after being subjected to the standing wave field. The mixing time and speed was 15 minutes and 2000 rpm respectively which was optimized experimentally for stable emulsion. Rushton impeller was used for high turbulence mixing. Results demonstrated the importance of optimizing the acoustic parameters (frequency, power) with respect to the emulsion droplet size distribution for improving the separation efficiency. The formation of bands and the accelerated separation of oil droplets are facilitated by the application of sufficient energy to the proper standing wave. This study showed that when ultrasonic was applied to the emulsion under limited frequency and power, coalescence was shown on the surface, meaning in a standing wave field, oil droplets aggregate and collide in the anti-nodal planes, where their coalescence and buoyancy occur when direct radiation force (Aggregating oil droplet), and secondary acoustic force (when coalescence takes place due to the causing of attractive or repulsive forces), therefore separation will happen. Results showed that the oil layer thickness recovered from the O/W emulsion subjected to the acoustic field was ~70% higher than that of gravitational separation alone. Results also showed that deviating from the standing wave frequency or delivering excessive acoustic power can result in random droplet motion, secondary emulsification, and a decrease in separation efficiency. An observation experiment was done using stable emulsions with droplet sizes ranging from 50 to 100 micron subjected at ultrasonic radiation with varying amount of acoustic power starting with small amount of powerand increased gradually until reach the maximum power; 111 to 280 watts, showedemulsion separation is progressing with maximum efficiency or standing wave is creating the maximum capacity for an emulsion dispersed content. This regime of system depends critically on the oil content of an emulsion. Also, computational work has been conducted using COMSOL Multiphysics for illustration of frequency influence on oil separation. This work provides novel information to direct the field implementation of in-line acoustic oil-water separation tool by identifying the key parameters that influence oil coalescence hence the separation efficiency of the tool.
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Alanazi, Khalid, R. Mohan, S. S. Kolla, and O. Shoham. "Experimental Study of Monovalent Salt and Hydrochloric Acid Solution Effects on the Stability of Blank Oil-Water Dispersion in Batch Separators." In ASME 2023 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/imece2023-112880.
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Abstract The effect of aqueous phase salinity and acidity on the stability of oil-water dispersion is poorly understood. This is because most research works use complex solutions of mixed monovalent and divalent salts to replicate the composition of brine solution in the aqueous phase of crude oil emulsion. Hence, the relevance of each form of ionic solution cannot be determined without isolating and analyzing a laboratory-created oil-water dispersion. Toward this objective, this study aims to investigate the impact of monovalent salt solution and acidic water on the stability of blank (emulsifier-free) oil-in-water (O/W) and water-in-oil (W/O) emulsion. Fluids were mixed at a constant stirrer speed (2,500 rpm) and time (5 minutes) for each investigated emulsion. Mineral oil (EXXSOL™ D110) and distilled water with density and viscosity ratios of 0.805 and 0.330, respectively, were chosen as the pure fluids. Sodium chloride (NaCl) was used to vary the concentration of monovalent salt (from 1 to 60 g/L) in the aqueous phase, whereas a 1.0 M hydrochloric acid solution was used to alter the acidity (pH = 4.80 to 1.88) of distilled water. Experiments ranging from less than a minute to several hours were conducted using four water cuts (WC = 25%, 50%, 75%, and 90%). The brine and acidic water phase had shown large impacts on the stability of O/W (90% and 75% WC) emulsions but had minor effects on W/O (25% and 50% WC) emulsions.
Reports on the topic "W/o emulsion"
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Wicker, Louise, and Nissim Garti. Entrapment and controlled release of nutraceuticals from double emulsions stabilized by pectin-protein hybrids. United States Department of Agriculture, 2004. http://dx.doi.org/10.32747/2004.7695864.bard.
Full textAbstract:
Original Objectives Specific objectives are to: (1) modify charge and hydrophobicity of pectins to improve emulsion stabilizing properties (2) develop emulsions that can be sterically stabilized using modified pectins and/or pectin/protein hybrids (3) obtain submicronal inner emulsion droplets (10-50 nanometers) with small and monodispersed double emulsion (1-2 μm) droplets with long-term stability (possibly by emulsified microemulsions) and (4) trigger and control the release at will. Background Methodology for encapsulation and controlled release of selected addenda, e.g. drugs, vitamins, phytochemicals, flavors, is of major impact in the food industries. Stable double emulsions with desired solubilization and release properties of selected addenda are formed using charge modified pectin or pectin-protein hybrids. Major conclusions, solutions, achievements * We developed methodology to isolate PME isozymes and prepared modified pectins in sufficient quantity to characterize, form single and double emulsions and test stability. *Amino acid sequence of PME isozymes was estimated and will facilitate cloning of PME for commercial application * The contribution of total charge and distribution of charge of modified pectin was determined *Soluble complexes or modified pectins and whey isolates are formed * Stable W/O/W double emulsions were formed that did not cream, had small particle size * Inner phase of double emulsions are nano-sized and stable. These new structures were termed emulsified microemulsions (EME) * Release of bioactives were controlled between a few days to months depending on layering on droplets by hybrids * Commercial testing by Israeli company of stability and release of Vitamin C showed good chemical stability Implications Resolved the major stability limitation of W/O/W emulsions. Resolved the questions regarding citrus PMEs and tailored pilot scale modification of pectins.
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Salcedo, Felipe, Jose Bejarano, Juan Diaz, Yina Ortega, and Ariel Vaca. Production of a starch-based polymeric coating with incorporation of bioactive principles from chemical synthesis to extend the shelf life of cavendish banana. Universidad de los Andes, 2024. https://doi.org/10.51573/andes.pps39.ss.bbb.4.
Full textAbstract:
Crown rot is a severe postharvest disease affecting tropical and subtropical fruits like mango, avocado, papaya, and banana. It is caused by fungal pathogens that penetrate the fruit, reducing its pulp and leading to premature ripening. Systemic fungicides have been used to control these fungi, typically applied to seeds, leaves, or fruits to prevent disease spread. However, traditional fungicides can pose toxicity risks to the environment and human health. Essential oils are chemical substances that can be found in plants and have antifungal capacity. Essential oils are being investigated as an alternative to traditional fungicides since they are less toxic to the environment and human health; however, they are more expensive and less efficient than traditional fungicides. Accordingly, chemically synthesizing the chemical compounds that are the active antifungal agent inside essential oils can be an ecological and effective approach to produce a new generation of antifungals. In this study, modified starch was investigated as a carrier for thymol (active antifungal agent in thyme oil) incorporation using four distinct methods. Emulsions of starch and thymol were prepared and spray dried to obtain a soluble powder that was used to produce coatings. The most effective method for thymol incorporation yields a retention of approximately 40% according to gas chromatography analysis. In-vitro results indicated that thymol incorporated into the matrix exhibited antifungal effects against key fungi responsible for crown rot disease in Cavendish bananas at concentrations greater than 6% w/w relative to the coating matrix.