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Sample records for internal phase emulsions

  1. Phase inversion of ionomer-stabilized emulsions to form high internal phase emulsions (HIPEs).

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    Zhang, Tao; Xu, Zhiguang; Cai, Zengxiao; Guo, Qipeng

    2015-06-28

    Herein, we report the phase inversion of ionomer-stabilized emulsions to form high internal phase emulsions (HIPEs) induced by salt concentration and pH changes. The ionomers are sulfonated polystyrenes (SPSs) with different sulfonation degrees. The emulsion types were determined by conductivity measurements, confocal microscopy and optical microscopy, and the formation of HIPE organogels was verified by the tube-inversion method and rheological measurements. SPSs with high sulfonation degrees (water-soluble) and low sulfonation degrees (water-insoluble) can stabilize oil-in-water emulsions; these emulsions were transformed into water-in-oil HIPEs by varying salt concentrations and/or changing the pH. SPS, with a sulfonation degree of 11.6%, is the most efficient, and as low as 0.2 (w/v)% of the organic phase is enough to stabilize the HIPEs. Phase inversion of the oil-in-water emulsions occurred to form water-in-oil HIPEs by increasing the salt concentration in the aqueous phase. Two phase inversion points from oil-in-water emulsions to water-in-oil HIPEs were observed at pH 1 and 13. Moreover, synergetic effects between the salt concentration and pH changes occurred upon the inversion of the emulsion type. The organic phase can be a variety of organic solvents, including toluene, xylene, chloroform, dichloroethane, dichloromethane and anisole, as well as monomers such as styrene, butyl acrylate, methyl methacrylate and ethylene glycol dimethacrylate. Poly(HIPEs) were successfully prepared by the polymerization of monomers as the continuous phase in the ionomer-stabilized HIPEs.

  2. Aggregation in a high internal phase emulsion observed by SANS and USANS

    International Nuclear Information System (INIS)

    Zank, Johann; Reynolds, P.A.; Jackson, A.J.; Baranyai, K.J.; Perriman, A.W.; White, J.W.; Barker, J.G.; Kim, Man-Ho

    2005-01-01

    Full text: As part of a wider study into high internal phase emulsions, we have prepared and studied by SANS and USANS the structure of an unstable emulsion consisting of 90% by volume saturated ammonium nitrate dispersed as micron-scale droplets in hexadecane, stabilised by the surfactant Pluronic L92. Similar emulsions produced using polyisobutylene-based surfactants, reported earlier, are highly stabilised by a significant number of surfactant rich reverse micelles a few nanometres in diameter in the oil phase. The aqueous-oil droplet interfaces are coated with a monolayer of surfactant, while a very small amount of surfactant is aggregated into micron-scale surfactant-rich objects. In contrast, the Pluronic emulsion contains insignificant numbers of reverse micelles and a complex multilayered interface between oil and aqueous phases. Now, the great majority of added surfactant is in the form of micron scale, fractally linked, blocks of lamellar phase at the aqueous-oil droplet interfaces. The lamellar phase can be characterised by the Bragg peaks observed in three different isotopic contrasts by SANS. We attribute the shear instability of the Pluronic emulsion to the more hydrophilic nature of the surfactant which causes both depletion of reverse micelles in the oil phase, and aggregation into the blocks of lamellar phase. (authors)

  3. Collective Rayleigh-Plateau Instability: A Mimic of Droplet Breakup in High Internal Phase Emulsion.

    Science.gov (United States)

    Mansard, Vincent; Mecca, Jodi M; Dermody, Dan L; Malotky, David; Tucker, Chris J; Squires, Todd M

    2016-03-22

    Using a microfluidic multi-inlet coflow system, we show the Rayleigh-Plateau instability of adjacent, closely spaced fluid threads to be collective. Although droplet size distributions and breakup frequencies are unaffected by cooperativity when fluid threads are identical, breakup frequencies and wavelengths between mismatched fluid threads become locked due to this collective instability. Locking narrows the size distribution of drops that are produced from dissimilar threads, and thus the polydispersity of the emulsion. These observations motivate a hypothesized two-step mechanism for high internal phase emulsification, wherein coarse emulsion drops are elongated into close-packed fluid threads, which break into smaller droplets via a collective Rayleigh Plateau instability. Our results suggest that these elongated fluid threads break cooperatively, whereupon wavelength-locking reduces the ultimate droplet polydispersity of high-internal phase emulsions, consistent with experimental observations.

  4. Phase behavior of medium and high internal phase water-in-oil emulsions stabilized solely by hydrophobized bacterial cellulose nanofibrils.

    Science.gov (United States)

    Lee, Koon-Yang; Blaker, Jonny J; Murakami, Ryo; Heng, Jerry Y Y; Bismarck, Alexander

    2014-01-21

    Water-in-oil emulsions stabilized solely by bacterial cellulose nanofibers (BCNs), which were hydrophobized by esterification with organic acids of various chain lengths (acetic acid, C2-; hexanoic acid, C6-; dodecanoic acid, C12-), were produced and characterized. When using freeze-dried C6-BCN and C12-BCN, only a maximum water volume fraction (ϕw) of 60% could be stabilized, while no emulsion was obtained for C2-BCN. However, the maximum ϕw increased to 71%, 81%, and 77% for C2-BCN, C6-BCN, and C12-BCN, respectively, 150 h after the initial emulsification, thereby creating high internal phase water-in-toluene emulsions. The observed time-dependent behavior of these emulsions is consistent with the disentanglement and dispersion of freeze-dried modified BCN bundles into individual nanofibers with time. These emulsions exhibited catastrophic phase separation when ϕw was increased, as opposed to catastrophic phase inversion observed for other Pickering emulsions.

  5. Graphene Oxide Nanoparticles and Their Influence on Chromatographic Separation Using Polymeric High Internal Phase Emulsions

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    Sidratul Choudhury

    2017-02-01

    Full Text Available This work presents the first instance of reversed-phase liquid chromatographic separation of small molecules using graphene oxide nanoparticle-modified polystyrene-divinylbenzene polymeric high internal phase emulsion (GONP PS-co-DVB polyHIPE materials housed within a 200-µm internal diameter (i.d. fused silica capillary. The graphene oxide nanoparticle (GONP-modified materials were produced as a potential strategy to increase both the surface area limitations and the reproducibility issues observed in monolithic stationary phase materials. GONP PS-co-DVB polyHIPEs were found to have a surface area up to 40% lower than unmodified polymeric high internal phase emulsion (polyHIPE stationary phases. However, despite having a surface area significantly lower than that of the unmodified material, the GONP-modified polyHIPEs demonstrated superior analyte adsorption properties. Reducing the GONP material did not have any significant impact on elution order or retention factor of the analytes, which was most likely due to low GONP loading attributed to the 250-nm GONPs utilised. The lower surface area of GONP-modified polyHIPEs provided similar separation efficiency and increased repeatability from injection to injection resulting in % relative standard deviations (%RSDs of less than 0.6%, indicating the potential offered by graphene oxide (GO-modified polyHIPES in flow through applications such as adsorption or separation processes.

  6. High internal phase emulsions (HIPEs) and polymerised HIPEs (PolyHIPEs)

    CERN Document Server

    Cameron, N R

    1995-01-01

    High internal phase emulsions (HIPEs) possess an internal phase volume ratio (phi) greater than 0.74. Novel non-aqueous HIPEs can be obtained from a non-polar organic liquid, such as petroleum ether, dispersed in a highly polar medium, such as formamide or dimethylsulfoxide. The system is stabilised with block copolymer surfactants of suitable HLB number. Polymerisation of a HIPE continuous phase leads to a highly porous monolithic material known as PolyHIPE. These polymers often have a completely open-cellular structure. The mechanism for the formation of this morphology was elucidated by performing scanning electron microscopy (SEM) on frozen HIPE samples at various stages of polymerisation. The point of transition from emulsion to open-cell polymer was found to coincide with the gel-point of the system, implying that the interconnected structure forms as a result of contraction of the continuous phase thin films on polymerisation. Novel PolyHIPE materials have been prepared by chemical modification of cros...

  7. High internal phase emulsions (HIPEs) and polymerised HIPEs (PolyHIPEs)

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, Neil R

    1995-07-01

    High internal phase emulsions (HIPEs) possess an internal phase volume ratio ({phi}) greater than 0.74. Novel non-aqueous HIPEs can be obtained from a non-polar organic liquid, such as petroleum ether, dispersed in a highly polar medium, such as formamide or dimethylsulfoxide. The system is stabilised with block copolymer surfactants of suitable HLB number. Polymerisation of a HIPE continuous phase leads to a highly porous monolithic material known as PolyHIPE. These polymers often have a completely open-cellular structure. The mechanism for the formation of this morphology was elucidated by performing scanning electron microscopy (SEM) on frozen HIPE samples at various stages of polymerisation. The point of transition from emulsion to open-cell polymer was found to coincide with the gel-point of the system, implying that the interconnected structure forms as a result of contraction of the continuous phase thin films on polymerisation. Novel PolyHIPE materials have been prepared by chemical modification of crosslinked polystyrene polymers. Sulfonation, nitration and bromination of monolithic samples to moderate levels and reasonable uniformity have been performed with mild reagents in homogeneous reaction conditions. In addition, crosslinked poly(phenyl methacrylate) (PPMA) PolyHIPE materials have been synthesised and chemically modified with tris(hydroxymethyl)-aminomethane (TRIS) under basic conditions, again to a moderate degree. Elastomeric PolyHIPE materials were prepared by copolymerisation of styrene and divinyl benzene (DVB) with 2-ethylhexyl (meth)acrylate. The variation of their glass transition temperatures (Tg) with composition was found to be non-linear. This is proposed to be due to both intra- and intermolecular interactions between polymer chains. Novel PolyHIPE polymers with enhanced thermal properties have been obtained by copolymerisation of an end-capped aryl ether sulfone oligomer with a number of monomers in a non-aqueous HIPE system

  8. Vinyl Ester Oligomer Crosslinked Porous Polymers Prepared via Surfactant-Free High Internal Phase Emulsions

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    Yun Zhu

    2012-01-01

    Full Text Available Using vinyl ester resin (VER containing styrene (or methyl methacrylate and vinyl ester oligomer (VEO as external phase, Pickering high internal phase emulsions (Pickering HIPEs having internal phase volume fraction of up to 95 vol% were prepared with copolymer particles as sole stabilizer. Polymerizing the external phase of these Pickering HIPEs led to porous polymers (poly-Pickering-HIPEs. Compared to the polystyrene- (PS- based poly-Pickering-HIPEs which were prepared with mixture of styrene and divinylbenzene (DVB as crosslinker, the poly-Pickering-HIPEs herein showed much higher elastic modulus and toughness. The elastic modulus of these poly-Pickering-HIPEs increased with increasing the VEO concentration in the external phase, while it decreased with increasing internal phase volume fraction. Increasing VEO concentration in the external phase also resulted in a decrease in the average void diameter as well as a narrow void diameter distribution of the resulting poly-Pickering-HIPEs. In addition, there were many small pores in the voids surface caused by the volume contraction of VER during the polymerization, which suggests a new method to fabricate porous polymers having a well-defined hierarchical pore structure.

  9. Porous TiO₂ materials through Pickering high-internal phase emulsion templating.

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    Li, Xiaodong; Sun, Guanqing; Li, Yecheng; Yu, Jimmy C; Wu, Jie; Ma, Guang-Hui; Ngai, To

    2014-03-18

    We report a facile method for preparing porous structured TiO2 materials by templating from Pickering high-internal phase emulsions (HIPEs). A Pickering HIPE with an internal phase of up to 80 vol %, stabilized by poly(N-isopropylacrylamide)-based microgels and TiO2 solid nanoparticles, was first formulated and employed as a template to prepare the porous TiO2 materials with an interconnected structure. The resultant materials were characterized by scanning electron microscopy, X-ray diffraction, and mercury intrusion. Our results showed that the parent emulsion droplets promoted the formation of macropores and interconnecting throats with sizes of ~50 and ~10 μm, respectively, while the interfacially adsorbed microgel stabilizers drove the formation of smaller pores (~100 nm) throughout the macroporous walls after drying and sintering. The interconnected structured network with the bimodal pores could be well preserved after calcinations at 800 °C. In addition, the photocatalytic activity of the fabricated TiO2 was evaluated by measuring the photodegradation of Rhodamine B in water. Our results revealed that the fabricated TiO2 materials are good photocatalysts, showing enhanced activity and stability in photodegrading organic molecules.

  10. The stability of high internal phase emulsions at low surfactant concentration studied by small angle neutron scattering.

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    Reynolds, Philip A; McGillivray, Duncan J; Mata, Jitendra P; Yaron, Peter N; White, John W

    2010-09-15

    The changes in structure of high internal phase emulsions at low concentrations and at elevated temperature are reported for comparison with the same emulsions under conditions well away from instability. Small angle neutron scattering measurements on aqueous ammonium nitrate droplets dispersed in hexadecane and stabilized by very small quantities of a polyisobutylene-based surfactant (PIBSA) as well as related inverse micellar solutions in hexadecane, have been made as a function of temperature and surfactant concentration. Experimental conditions here favour larger and more deformable droplets than in previous studies. Besides the expected micelles and adsorbed surfactant, planar bilayers of micron lateral extent between touching droplets cover 20% of the droplet surface. Another difference from previous experiments is that the oil phase in the emulsions, and corresponding inverse micellar solutions are different in micellar radii and composition. The differences, and changes with surfactant concentration and temperature, are attributed to fractionation of the polydisperse PIBSA in the emulsions, but not the inverse micellar solutions. At low PIBSA concentration and high temperature the SANS shows emulsion decomposing into separate oil and aqueous phases. This occurs when the micelle concentration reaches a very small but measurable value. The inverse micelles may suppress by steric action long wavelength unstable capillary waves in the bilayers. Depletion repulsion forces here have a minor role in the emulsion stabilization. Copyright 2010 Elsevier Inc. All rights reserved.

  11. An easily regenerable enzyme reactor prepared from polymerized high internal phase emulsions

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    Ruan, Guihua, E-mail: guihuaruan@hotmail.com [Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guangxi 541004 (China); Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541004 (China); Wu, Zhenwei; Huang, Yipeng; Wei, Meiping; Su, Rihui [Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guangxi 541004 (China); Du, Fuyou, E-mail: dufu2005@126.com [Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guangxi 541004 (China); Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area, Guilin University of Technology, Guilin 541004 (China)

    2016-04-22

    A large-scale high-efficient enzyme reactor based on polymerized high internal phase emulsion monolith (polyHIPE) was prepared. First, a porous cross-linked polyHIPE monolith was prepared by in-situ thermal polymerization of a high internal phase emulsion containing styrene, divinylbenzene and polyglutaraldehyde. The enzyme of TPCK-Trypsin was then immobilized on the monolithic polyHIPE. The performance of the resultant enzyme reactor was assessed according to the conversion ability of N{sub α}-benzoyl-L-arginine ethyl ester to N{sub α}-benzoyl-L-arginine, and the protein digestibility of bovine serum albumin (BSA) and cytochrome (Cyt-C). The results showed that the prepared enzyme reactor exhibited high enzyme immobilization efficiency and fast and easy-control protein digestibility. BSA and Cyt-C could be digested in 10 min with sequence coverage of 59% and 78%, respectively. The peptides and residual protein could be easily rinsed out from reactor and the reactor could be regenerated easily with 4 M HCl without any structure destruction. Properties of multiple interconnected chambers with good permeability, fast digestion facility and easily reproducibility indicated that the polyHIPE enzyme reactor was a good selector potentially applied in proteomics and catalysis areas. - Graphical abstract: Schematic illustration of preparation of hypercrosslinking polyHIPE immobilized enzyme reactor for on-column protein digestion. - Highlights: • A reactor was prepared and used for enzyme immobilization and continuous on-column protein digestion. • The new polyHIPE IMER was quite suit for protein digestion with good properties. • On-column digestion revealed that the IMER was easy regenerated by HCl without any structure destruction.

  12. Separation of heavy metals from water by functionalized glycidyl methacrylate poly (high internal phase emulsions).

    Science.gov (United States)

    Huš, Sebastjan; Kolar, Mitja; Krajnc, Peter

    2016-03-11

    Removal of silver, lead and cadmium ions from both model solutions and real contaminated water was achieved, in a flow through manner, by using highly porous functionalized poly(glycidyl methacrylate) materials, prepared by the polymerisation of high internal phase emulsions (polyHIPE), with significant sorption differences between metals allowing for selective removal. PolyHIPEs, initially prepared from glycidyl methacrylate as a functional monomer, were functionalized with pentaerythritol tetrakis(3-mercaptopropionate), 1,9-nonanedithiol and 2-aminobenzenethiol via the epoxy ring opening on the polymer supports and applied in a flow-through manner via encasements into dedicated disk holders. Capacity of 21.7mg Ag per gram of polymer was found for 1,9-nonanedithiol functionalized polymers, while the capacity was decreasing with the decreasing ionic radius of the metal; the dynamics of sorption also depended on metal ion size and furthermore on the thiol used for the polymer functionalization. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Interconnected Porous Material Prepared Via High Internal Phase Emulsion Stabilized by Mixture of Fe3O4 and Tween85

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    Yang Huaqing

    2016-01-01

    Full Text Available PolyHIPE monoliths with open-cell structure were prepared using an oil-in-water Pickering high internal phase emulsion (HIPEs template. Fe3O4 nanoparticles and Tween 85 were used to stabilize the HIPE. The effects of surfactant concentration, nanoparticle amount and internal phase fraction on the average void and interconnecting pore diameter and interconnectivity degree were investigated. Efficiency of these PolyHIPEs as catalyst for Fenton reaction to decompose methyl orange was tested. The results showed that the PolyHIPE was an excellent and reusable supporter for Fenton reaction.

  14. Hierarchical high internal phase emulsions and transparent oleogels stabilized by quillaja saponin-coated nanodroplets for color performance.

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    Chen, Xiao-Wei; Wang, Jin-Mei; Guo, Jian; Wan, Zhi-Li; Yin, Shou-Wei; Yang, Xiao-Quan

    2017-02-22

    Herein, we report novel high internal phase emulsions and transparent oleogels that exhibit a hierarchical configuration by manipulating the spatial assembly of a natural small molecular-weight quillaja saponin for color performance. Quillaja saponin (QS) is a natural triterpenoid bidesmosidic from the soapbark tree (Quillaja saponaria Molina). Fairly monodispersed QS-coated nanodroplets (∼154 nm) were prepared using the ultrasonic emulsification strategy, and then used as block stabilizers for the fabrication of stable oil-in-water high internal phase emulsions (HIPEs, ϕ = 0.75). The resulting HIPEs can be easily converted into transparent oleogels with a very high oil loading (99.7%) through oven drying (70 °C). The jelly-like oleogels exhibit weak elastic, shear thinning behavior, good thixotropic recovery, and thermostabilization properties, which might be provided by the percolating 3D network of QS fibrils in the oil phase. We spatially tuned the color performance of the HIPEs and subsequent oleogels by locating the compositions of food colorants in different sections of their hierarchal architecture. The design and construction of hierarchical HIPEs and oleogels provide a promising new route for multitask functional delivery applications in various fields including food, cosmetics, and medical applications.

  15. High-internal-phase emulsions stabilized by metal-organic frameworks and derivation of ultralight metal-organic aerogels

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    Zhang, Bingxing; Zhang, Jianling; Liu, Chengcheng; Peng, Li; Sang, Xinxin; Han, Buxing; Ma, Xue; Luo, Tian; Tan, Xiuniang; Yang, Guanying

    2016-02-01

    To design high-internal-phase emulsion (HIPE) systems is of great interest from the viewpoints of both fundamental researches and practical applications. Here we demonstrate for the first time the utilization of metal-organic framework (MOF) for HIPE formation. By stirring the mixture of water, oil and MOF at room temperature, the HIPE stabilized by the assembly of MOF nanocrystals at oil-water interface could be formed. The MOF-stabilized HIPE provides a novel route to produce highly porous metal-organic aerogel (MOA) monolith. After removing the liquids from the MOF-stabilized HIPE, the ultralight MOA with density as low as 0.01 g·cm-3 was obtained. The HIPE approach for MOA formation has unique advantages and is versatile in producing different kinds of ultralight MOAs with tunable porosities and structures.

  16. Ultrasonic Phase Velocity and Attenuation in Emulsions

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    Nesse, Oe.; Froeysa, K.E.

    1996-12-31

    This paper presents measurements of ultrasonic phase velocity and attenuation in emulsions in the frequency range 250 kHz to 14 MHz for volume fractions of dispersed phase varying from 2% to 80%. The experimental data are compared to theoretical predictions based on multiple scattering models. Good agreement is found between experimental data and theory for an oil-in-water emulsion at volume fractions up to 50%. For volume fractions of the dispersed phase above 50%, important discrepancies are found between the multiple scattering theories and the experiments for oil-in-water emulsions and for water-in-oil emulsions. However, measurements on water-in-oil emulsions and attenuation in emulsions of aliphatic oils in water deviate considerably from the theories. Measurements of phase velocity and attenuation in emulsions may provide information about droplet size, volume fraction of the dispersed phase and determine whether the emulsion is oil or water continuous. 10 refs., 6 figs.

  17. Novel/conceptual floating pulsatile system using high internal phase emulsion based porous material intended for chronotherapy.

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    Sher, Praveen; Ingavle, Ganesh; Ponrathnam, Surendra; Benson, James R; Li, Nai-Hong; Pawar, Atmaram P

    2009-01-01

    The aim of the present study was to design a novel/conceptual delivery system using ibuprofen, anticipated for chronotherapy in arthritis with porous material to overcome the formulation limits (multiple steps, polymers, excipients) and to optimize drug loading for a desired release profile suitable for in vitro investigations. The objective of this delivery system lies in the availability of maximum drug amount for absorption in the wee hours as recommended. Drug loading using 3(2) factorial design on porous carrier, synthesized by high internal phase emulsion technique using styrene and divinylbenzene, was done via solvent evaporation using methanol and dichloromethane. The system was evaluated in vitro for drug loading, encapsulation efficiency, and surface characterization by scanning electron, atomic force microscopy, and customized drug release study. This study examined critical parameters such as solvent volume, drug amount, and solvent polarity on investigations related to drug adsorption and release mostly favoring low-polarity solvent dichloromethane. Overall release in all batches ranged 0.98-52% in acidic medium and 71-94% in basic medium. These results exhibit uniqueness in achieving the least drug release of 0.98%, an ideal one, without using any release modifiers, making it distinct from other approaches/technologies for time and controlled release and for chronotherapy.

  18. Interconnectivity of macroporous molecularly imprinted polymers fabricated by hydroxyapatite-stabilized Pickering high internal phase emulsions-hydrogels for the selective recognition of protein.

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    Sun, Yanhua; Li, Yuqing; Xu, Jiangfeng; Huang, Ling; Qiu, Tianyun; Zhong, Shian

    2017-07-01

    Hydroxyapatite hybridized molecularly imprinted polydopamine polymers with selective recognition of bovine hemoglobin (BHb) were successfully prepared via Pickering oil-in-water high internal phase emulsions-hydrogels and molecularly imprinting technique. The emulsions were stabilized by hydroxyapatite of which the wettability was modified by 3-methacryloxypropyltrimethoxysilane. The materials were characterized by SEM, IR and TGA. The results showed that the BHb imprinted polymers based on Pickering hydrogels (Hydro-MIPs) possess macropores ranging from 20μm to 50μm, and their large numbers of amino groups and hydroxyl groups result in a favorable adsorption capacity for BHb. The maximum adsorption capacity of Hydro-MIPs for BHb was 438mg/g, 3.27 times more than that of the non-imprinted polymers (Hydro-NIPs). The results indicated that Hydro-MIPs possessing well-defined hierarchical porous structures exhibited outstanding recognition behavior towards the target protein molecules. This work provided a promising alternative method for the fabrication of polymer materials with tunable and interconnected pores structures for the separation and purification of protein in vitro. Copyright © 2017. Published by Elsevier B.V.

  19. Gelatin Particle-Stabilized High-Internal Phase Emulsions for Use in Oral Delivery Systems: Protection Effect and in Vitro Digestion Study.

    Science.gov (United States)

    Tan, Huan; Zhao, Lifeng; Tian, Sisi; Wen, Hui; Gou, Xiaojun; Ngai, To

    2017-02-01

    The potential application of Pickering high-internal phase emulsions (HIPEs) in the food and pharmaceutical industries has yet to be fully developed. Herein, we synthesized fairly monodisperse, nontoxic, autofluorescent gelatin particles for use as sole stabilizers for fabricating oil-in-water (O/W) HIPEs in an effort to improve the protection and bioaccessibility of entrapped β-carotene. Our results showed that the concentration of gelatin particles determined the formation, microstructure, droplet size distribution, and digestion profile of the HIPEs. For storage stability, the retention of β-carotene in HIPEs was significantly higher than in dispersion in bulk oil, even after storage for 27 days. In addition, in vitro digestion experiments indicated that the bioaccessibility of β-carotene was improved 5-fold in HIPEs. This study will help establish a correlation between the physicochemical properties of gelatin particle-stabilized HIPEs with their applications in the oral delivery of bioactive nutraceuticals.

  20. A soluble star-shaped silsesquioxane-cored polymer-towards novel stabilization of pH-dependent high internal phase emulsions.

    Science.gov (United States)

    Xing, Yuxiu; Peng, Jun; Xu, Kai; Gao, Shuxi; Gui, Xuefeng; Liang, Shengyuan; Sun, Longfeng; Chen, Mingcai

    2017-08-30

    A well-defined pH-responsive star-shaped polymer containing poly(N,N-dimethylaminoethyl methacrylate) (PDMA) arms and a cage-like methacryloxypropyl silsesquioxane (CMSQ-T 10 ) core was used as an interfacial stabilizer for emulsions consisting of m-xylene and water. We explored the properties of the CMSQ/PDMA star-shaped polymer using the characteristic results of nuclear magnetic resonance (NMR) spectroscopy, size exclusion chromatography (SEC), dynamic light scattering (DLS), and zeta potential and conductivity measurements. The interfacial tension results showed that the CMSQ/PDMA star-shaped polymer reduced the interfacial tension between water and oil in a pH-dependent manner. Gelled high internal phase emulsions (HIPEs) including o/w and w/o types were formed in the pH ranges of 1.2-5.8 and 9.1-12.3 with the CMSQ/PDMA star-shaped polymer as a stabilizer, when the oil fractions were 80-90 vol% and 10-20 vol%, respectively. The soluble star-shaped polymer aggregated spontaneously to form a microgel that adsorbed to the two immiscible phases. Images of the fluorescently labeled polymers demonstrated that there was a star-shaped polymer in the continuous phase, and the non-Pickering stabilization based on the percolating network of the star-shaped polymer also contributed to the stabilization of the HIPE. This pH-dependent HIPE was prepared with a novel stabilization mechanism consisting of microgel adsorption and non-Pickering stabilization. Moreover, the preparation of HIPEs provided the possibility of their application in porous materials and responsive materials.

  1. Responsive Poly(acrylic acid) and Poly(N-isopropylacrylamide) Monoliths by High Internal Phase Emulsion (polyHYPE) Templating

    Czech Academy of Sciences Publication Activity Database

    Kovačič, S.; Jeřábek, Karel; Krajnc, P.

    2011-01-01

    Roč. 212, č. 19 (2011), s. 2151-2158 ISSN 1022-1352 R&D Projects: GA MŠk MEB090811 Grant - others:CE PoliMat(SI) 3211-10-000057 Institutional research plan: CEZ:AV0Z40720504 Keywords : emulsion templating * monoliths * polyHIPE Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.361, year: 2011

  2. Preliminary In Vitro Assessment of Stem Cell Compatibility with Cross-Linked Poly(ε-caprolactone urethane Scaffolds Designed through High Internal Phase Emulsions

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    Sylvie Changotade

    2015-01-01

    Full Text Available By using a high internal phase emulsion process, elastomeric poly(ε-caprolactone urethane (PCLU scaffolds were designed with pores size ranging from below 150 μm to 1800 μm and a porosity of 86% making them suitable for bone tissue engineering applications. Moreover, the pores appeared to be excellently interconnected, promoting cellularization and future bone ingrowth. This study evaluated the in vitro cytotoxicity of the PCLU scaffolds towards human mesenchymal stem cells (hMSCs through the evaluation of cell viability and metabolic activity during extract test and indirect contact test at the beginning of the scaffold lifetime. Both tests demonstrated that PCLU scaffolds did not induce any cytotoxic response. Finally, direct interaction of hMSCs and PCLU scaffolds showed that PCLU scaffolds were suitable for supporting the hMSCs adhesion and that the cells were well spread over the pore walls. We conclude that PCLU scaffolds may be a good candidate for bone tissue regeneration applications using hMSCs.

  3. High temperature structural, polymeric foams from high internal emulsion polymerization

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    Hoisington, M.A.; Duke, J.R.; Apen, P.G.

    1996-02-01

    In 1982, a high internal phase emulsion (HIPE) polymerization process to manufacture microcellular, polymeric foam systems was patented by Unilever. This patent discloses a polymerization process that occurs in a water-in-oil emulsion in which the water represents at least 76% of the emulsion by volume. The oil phase consists of vinyl monomers such as styrene and acrylates that are crosslinked by divinyl monomers during polymerization. After polymerization and drying to remove the water phase, the result is a crosslinked polymer foam with an open cell microstructure that is homogeneous throughout in terms of morphology, density, and mechanical properties. Since 1982, numerous patents have examined various HIPE polymerized foam processing techniques and applications that include absorbents for body fluids, cleaning materials, and ion exchange systems. All the published HIPE polymerized foams have concentrated on materials for low temperature applications. Copolymerization of styrene with maleic anhydride and N-substituted maleimides to produce heat resistant thermoplastics has been studied extensively. These investigations have shown that styrene will free radically copolymerize with N-substituted maleimides to create an alternating thermoplastic copolymer with a Tg of approximately 200{degrees}C. However, there are many difficulties in attempting the maleimide styrene copolymerization in a HIPE such as lower polymerization temperatures, maleimide solubility difficulties in both styrene and water, and difficulty obtaining a stable HIPE with a styrene/maleimide oil phase. This work describes the preparation of copolymer foams from N-ethylmaleimide and Bis(3-ethyl-5-methyl-4-maleimide-phenyl)methane with styrene based monomers and crosslinking agents.

  4. Osmotic-induced phase inversion of multiple W/O/W into a W/O emulsion: rheological study of an inverted W/O emulsion

    International Nuclear Information System (INIS)

    Fredro-Kumbaradzi, Emilija; Simov, Angel; Popovska-Pavlovska, Frederika

    1995-01-01

    Osmotic induced phase inversion of a W/O/W emulsion due to the presence of NaCl in the internal aqueous phase is discussed in this paper. Visco metric measurements of the obtained W/O emulsion were also carried out in order to determine its rheological properties as well as its stability during storage. Pseudo plastic flow and negative thixotropy behavior were observed under different shearing conditions. Negative thixotropy behavior, which is most likely a result of emulsion dispersion status changes, increased with increased program time, holding time at the maximum shear rate, and max. shear rate, but decreased with repeated time of shear. Changes in the flow curves under different shear conditions were not very significant. Also, no significant changes in the rheological behavior were noticed during four weeks storage of the inverted emulsion samples at room temperature. Thus, the inverted emulsion of a W/O type is a relatively stable system. (Author)

  5. Membranes as separators of dispersed emulsion phases

    NARCIS (Netherlands)

    Lefferts, A.G.

    1997-01-01

    The reuse or discharge of industrial waste waters, containing small fractions of dispersed oil, requires a purification treatment for which membranes can be used. If only little oil is present, removal of the dispersed phase might be preferable to the more commonly applied removal of the

  6. Effect of citronella essential oil fractions as oil phase on emulsion stability

    Science.gov (United States)

    Septiyanti, Melati; Meliana, Yenny; Agustian, Egi

    2017-11-01

    The emulsion system consists of water, oil and surfactant. In order to create stable emulsion system, the composition and formulation between water phase, surfactant and oil phase are very important. Essential oil such as citronella oil has been known as active ingredient which has ability as insect repellent. This research studied the effect of citronella oil and its fraction as oil phase on emulsion stability. The cycle stability test was conducted to check the emulsion stability and it was monitored by pH, density, viscosity, particle size, refractive index, zeta potential, physical appearance and FTIR for 4 weeks. Citronellal fraction has better stability compared to citronella oil and rhodinol fraction with slight change of physical and chemical properties before and after the cycle stability test. However, it is need further study to enhance the stability of the emulsion stability for this formulation.

  7. Performance evaluation of organic emulsion liquid membrane on phenol removal

    OpenAIRE

    Ng, Yee Sern; Jayakumar, N.S.; Hashim, M.A.

    2017-01-01

    The percentage removal of phenol from aqueous solution by emulsion liquid membrane and emulsion leakage was investigated experimentally for various parameters such as membrane:internal phase ratio, membrane:external phase ratio, emulsification speed, emulsification time, carrier concentration, surfactant concentration and internal agent concentration. These parameters strongly influence the percentage removal of phenol and emulsion leakage. Under optimum membrane properties, the percentage re...

  8. Laboratory performance evaluation of CIR-emulsion and its comparison against CIR-foam test results from phase III.

    Science.gov (United States)

    2009-12-01

    Currently, no standard mix design procedure is available for CIR-emulsion in Iowa. The CIR-foam mix : design process developed during the previous phase is applied for CIR-emulsion mixtures with varying : emulsified asphalt contents. Dynamic modulus ...

  9. Experimental study on heat capacity of paraffin/water phase change emulsion

    International Nuclear Information System (INIS)

    Huang, L.; Noeres, P.; Petermann, M.; Doetsch, C.

    2010-01-01

    A paraffin/water phase change emulsion is a multifunctional fluid in which fine paraffin droplets are dispersed in water by a surfactant. This paper presents an experimental study on the heat capacity of an emulsion containing 30 wt.% paraffin in a test rig. The results show that the heat capacity of the emulsion consists of the sensible heat capacity of water and that of the paraffin as well as the latent heat capacity of the paraffin during the phase transition solid-liquid. The emulsion is an attractive alternative to chilled water for comfort cooling applications, because it has a heat capacity of 50 kJ/kg from 5 to 11 deg. C, which is two times as high as that of water in the same temperature range.

  10. A Computational Study of Internal Flows in a Heated Water-Oil Emulsion Droplet

    KAUST Repository

    Sim, Jaeheon

    2015-01-05

    The vaporization characteristics of water-oil emulsion droplets are investigated by high fidelity computational simulations. One of the key objectives is to identify the physical mechanism for the experimentally observed behavior that the component in the dispersed micro-droplets always vaporizes first, for both oil-in-water and water-in-oil emulsion droplets. The mechanism of this phenomenon has not been clearly understood. In this study, an Eulerian-Lagrangian method was implemented with a temperature-dependent surface tension model and a dynamic adaptive mesh refinement in order to effectively capture the thermo-capillary effect of a micro-droplet in an emulsion droplet efficiently. It is found that the temperature difference in an emulsion droplet creates a surface tension gradient along the micro-droplet surface, inducing surface movement. Subsequently, the outer shear flow and internal flow circulation inside the droplet, referred to as the Marangoni convection, are created. The present study confirms that the Marangoni effect can be sufficiently large to drive the micro-droplets to the emulsion droplet surface at higher temperature, for both water-in-oil and oil-and-water emulsion droplets. A further parametric study with different micro-droplet sizes and temperature gradients demonstrates that larger micro-droplets move faster with larger temperature gradient. The oil micro-droplet in oil-in-water emulsion droplets moves faster due to large temperature gradients by smaller thermal conductivity.

  11. Effects of NOx-inhibitor agent on fuel properties of three-phase biodiesel emulsions

    International Nuclear Information System (INIS)

    Lin, Cherng-Yuan; Lin, Hsiu-An

    2008-01-01

    Biodiesel is one of the more promising alternative clean fuels to fossil fuel, which can reduce the emissions of fossil fuel burning, and possibly resolve the energy crisis caused by the exhaustion of petroleum resources in the near future. The burning of biodiesel emits much less gaseous emissions and particulate matter primarily because of its dominant combustion efficiency. However, the high oxygen content in biodiesel not only promotes the burning process but also enhances NO x formation when biodiesel is used as fuel. Biodiesel emulsion and the additive of NO x -inhibitor agent are considered to reduce levels of NO x emissions in this experimental study. The biodiesel was produced by transesterification reaction accompanied with peroxidation process. A three-phase biodiesel emulsion of oil-in water drops-in oil (O/W/O) and an O/W/O biodiesel emulsion containing aqueous ammonia were prepared afterwards. The effect of the existence of NO x -inhibitor agent on the fuel properties and the emulsion characteristics of the O/W/O biodiesel emulsions were investigated. The experimental results show that the burning of the O/W/O biodiesel emulsion and the O/W/O biodiesel emulsion containing aqueous ammonia had larger fraction of fuel burnt and thus larger heat release than the neat biodiesel if water content is not considered for the calculation of heating value. The addition of aqueous ammonia within the dispersed phase of the O/W/O biodiesel emulsion appeared to deteriorate the emulsification characteristics. A smaller quantity of emulsion and greater kinematic viscosity were formed while a larger carbon residue and actual reaction-heat release also appeared for this O/W/O biodiesel emulsion. Aqueous ammonia in the O/W/O biodiesel emulsion produces a higher pH value as well. In addition, the number as well as the volumetric fraction of the dispersed water droplets is reduced for the O/W/O biodiesel emulsion that contains aqueous ammonia. (author)

  12. Regeneration of liquid membrane without breaking emulsion

    International Nuclear Information System (INIS)

    Dines, M.B.

    1982-01-01

    A process for removing a species from a fluid which comprises (A) contacting said fluid with an emulsion, said emulsion having an external phase and an internal phase, said external phase being immiscible with said fluid and said species being permeable to said external phase; (B) permeating said species through said external phase into said internal phase; (C) converting said permeated species in said internal phase, into a species which is impermeable to said external phase; (D) separating said emulsion from said fluid; (E) converting the impermeable species of step (C) into a species which is permeable to said external phase by means of an oxidation-reduction reaction; and (F) permeating the permeable species of step (E) through said external phase. The instant process may be carried out in the reverse manner, i.e. the fluid including the species to be removed can be the internal phase of an emulsion or foam and thus permeate through the external phase. Preferably the fluid is an aqueous solution and the emulsion is a water-in-oil emulsion. The impermeable species of step (C) may be converted into a species which is permeable to said external phase by irradiating with light (uv or visible), by heating or by isolating said impermeable species from light. Preferably the permeable species in the internal phase is U + 6 e.g. As UO 2+ 2 , which is trapped in the internal phase of the emulsion by reduction to U + 4 an impermeable species, in the presence of a hydroquinone and light. Simultaneously hydroquinone is converted to quinone. After separation of the emulsion containing uranium in the +4 nonpermeable state from the aqueous solution, the emulsion is subjected to agitation in the presence of a fresh aqueous solution and in the absence of light whereby the quinone oxidizes the U + 4 to U + 6 e.g. UO 2+ 2 which then permeates through said external phase into said fresh aqueous solution

  13. Electric field-driven, magnetically-stabilized ferro-emulsion phase contactor

    Science.gov (United States)

    Scott, Timothy C.

    1990-01-01

    Methods and systems for interfacial surface area contact between a dispersed phase liquid and a continuous phase liquid in counter-current flow for purposes such as solvent extraction. Initial droplets of a dispersed phase liquid material containing ferromagnetic particles functioning as a "packing" are introduced to a counter-current flow of the continuous phase. A high intensity pulsed electric field is applied so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets in contact with the continuous phase material. A magnetic field is applied to control the position of the ferromagnetic emulsion for enhanced coalescence of the daughter droplets into larger reformed droplets.

  14. Experimental analysis of a low cost phase change material emulsion for its use as thermal storage system

    International Nuclear Information System (INIS)

    Delgado, Mónica; Lázaro, Ana; Mazo, Javier; Peñalosa, Conchita; Dolado, Pablo; Zalba, Belén

    2015-01-01

    Highlights: • A low cost PCM emulsion has been analyzed as thermal energy storage system. • Its thermophysical and rheological properties have been determined. • The system shows advantages in terms of energy density and heat transfer rate. • The PCM emulsion system has been compared to other thermal energy storage systems. - Abstract: A 46 l commercial tank with a helical coil heat exchanger and containing a low cost phase change material emulsion has been experimentally analyzed as a thermal energy storage system in terms of volumetric energy density and heat transfer rate, for its subsequent comparison with other thermal energy storage systems. This phase change material emulsion shows a phase change temperature range between 30 and 50 °C, its solids content is about 60% with an average particle size of 1 μm. The low cost phase change material emulsion shows a thermal storage capacity by mass 50% higher than water and an increase in viscosity up to 2–5 orders of magnitude. The results have shown that the global heat transfer coefficient of the phase change material emulsion tank is around 2–6 times higher than for conventional latent systems previously analyzed in literature, although 5 times lower than if it contains water. The phase change material emulsion tank presents an energy density 34% higher than the water tank, which makes it a promising solution. Measures to improve its performance are also studied in this work.

  15. Transitional phase inversion of crude oil emulsions by solid particles; Inversao transicional de emulsoes de petroleo com particulas solidas

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Troner A. de; Scheer, Agnes P.; Soares, Cristyan R.; Luz Junior, Luiz Fernando de Lima [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil); Oliveira, Marcia Cristina K. de [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2008-07-01

    In petroleum production water-in-oil emulsions (W/O) can be found, due to simultaneous flowing of the oil and formation water. This emulsions provide an increase in the viscosity; that can be reduced for the phase inversion in oil-in-water emulsions (O/W), resulting in pressure drop and consequently cost production reduction. The petroleum emulsions W/O were prepared at 60 deg C, with 50% v/v of saline water containing 50 g.L{sup -1} of NaCl. The hydrophilic solids content was varied between 0,5% and 8%, mass fraction, related to the water. The quantity of solids needed to phase inversion of the emulsion was measured by conductivimetry. The stability of the emulsions was verified, at 60 deg C, for the time determination in order to have two phases in four hours, checking the viability for production; and during 24 hours, checking the viability for transportation. Under dynamics conditions, was also noted the stability at 20 deg C, for reproduce the flowing condition. Two of the hydrophilic particles tested in the transitional phase inversion of petroleum emulsions presented better results in quantity and stability. Preliminaries rheological properties measurements were carried out adjusting the temperature of the sample in the range of 30 deg C to 12 deg C a shear rate from 20s{sup -1} to 250s {sup -1}, viscosity decrease was observed until two orders of magnitude. (author)

  16. Performance evaluation of organic emulsion liquid membrane on phenol removal.

    Science.gov (United States)

    Ng, Y S; Jayakumar, N S; Hashim, M A

    2010-12-15

    The percentage removal of phenol from aqueous solution by emulsion liquid membrane and emulsion leakage was investigated experimentally for various parameters such as membrane:internal phase ratio, membrane:external phase ratio, emulsification speed, emulsification time, carrier concentration, surfactant concentration and internal agent concentration. These parameters strongly influence the percentage removal of phenol and emulsion leakage. Under optimum membrane properties, the percentage removal of phenol was as high as 98.33%, with emulsion leakage of 1.25%. It was also found that the necessity of carrier for enhancing phenol removal was strongly dependent on the internal agent concentration. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. Self-Assembling, Stable Photonic Bend-Gap Phases in Emulsions of Chiral Nematics with Isotropic Fluids

    Science.gov (United States)

    Huang, Chien-Yueh; Petschek, R. G.

    1998-03-01

    We investigate the possible mesophases in emulsions of chiral nematic liquid crystals with immiscible isotropic fluids and surfactants. The interactions between the orientational fields of the chiral nematics and the surfactant membranes together with the topological constraints affect stability of micellar geometries and produce a new phase diagram. We compare the free energies of various candidate phases. Appropriate, likely realizable conditions on the surfactant and the pitch of the liquid crystal result in thermodynamically stable blue-phase like phases for a relatively wide range of parameters. Processing such emulsions may result in materials with photonic band gaps.

  18. Pickering emulsion: A novel template for microencapsulated phase change materials with polymer–silica hybrid shell

    International Nuclear Information System (INIS)

    Yin, Dezhong; Ma, Li; Liu, Jinjie; Zhang, Qiuyu

    2014-01-01

    MePCMs (microencapsulated phase change materials) with covalently bonded SiO 2 /polymer hybrid as shell were fabricated via Pickering emulsion polymerization stabilized solely by organically-modified SiO 2 particles. Morphology and core–shell structure of these microcapsules were observed by scanning electron microscopy (SEM). Thermal properties of microencapsulated 1-dodecanol were determined using DSC (differential scanning calorimetry) and TGA (thermal gravimetric analysis). The results indicate that mass ratio of St (styrene)/DVB (divinylbenzene)/dodecanol has great effect on the morphology, inner structure, microencapsulation efficiency and durability of resultant MePCMs. When ratio of St/DVB/dodecanol was 5/1/12, dodecanol content of as much as 62.8% is obtained and the utility efficiency of dodecanol reaches 94.2%. The prepared MePCMs present good durability and thermal reliability. 2.2% of core material leached away the microcapsule after suspended in water for 10 days and 5.8% of core material leached after 2000 accelerated thermal cycling. Our study demonstrated that Pickering emulsion polymerization is a simple and robust method for the preparation of MePCMs with polymer–inorganic hybrids as shell. - Highlights: • We fabricated MePCM via surfactant-free Pickering emulsion polymerization. • The shell of MePCM was composed of PS/SiO 2 organic–inorganic hybrids. • The phase change enthalpy of MePCM is 125.0 J g −1 and the utility efficiency of 1-dodecanol reached 94.2%. • Only 2.2% and 5.8% of core material lost after durability test and 2000 accelerated thermal cycling respectively

  19. Internal flow inside droplets within a concentrated emulsion during droplet rearrangement

    Science.gov (United States)

    Leong, Chia Min; Gai, Ya; Tang, Sindy K. Y.

    2018-03-01

    Droplet microfluidics, in which each droplet serves as a micro-reactor, has found widespread use in high-throughput biochemical screening applications. These droplets are often concentrated at various steps to form a concentrated emulsion. As part of a serial interrogation and sorting process, such concentrated emulsions are typically injected into a tapered channel leading to a constriction that fits one drop at a time for the probing of droplet content in a serial manner. The flow physics inside the droplets under these flow conditions are not well understood but are critical for predicting and controlling the mixing of reagents inside the droplets as reactors. Here we investigate the flow field inside droplets of a concentrated emulsion flowing through a tapered microchannel using micro-particle image velocimetry. The confining geometry of the channel forces the number of rows of drops to reduce by one at specific and uniformly spaced streamwise locations, which are referred to as droplet rearrangement zones. Within each rearrangement zone, the phase-averaged velocity results show that the motion of the droplets involved in the rearrangement process, also known as a T1 event, creates vortical structures inside themselves and their adjacent droplets. These flow structures increase the circulation inside droplets up to 2.5 times the circulation in droplets at the constriction. The structures weaken outside of the rearrangement zones suggesting that the flow patterns created by the T1 process are transient. The time scale of circulation is approximately the same as the time scale of a T1 event. Outside of the rearrangement zones, flow patterns in the droplets are determined by the relative velocity between the continuous and disperse phases.

  20. Microencapsulation of a hydrophilic model molecule through vibration nozzle and emulsion phase inversion technologies.

    Science.gov (United States)

    Dorati, Rossella; Genta, Ida; Modena, Tiziana; Conti, Bice

    2013-01-01

    The goal of the present work was to evaluate and discuss vibration nozzle microencapsulation (VNM) technology combined to lyophilization, for the microencapsulation of a hydrophilic model molecule into a hydrophilic polymer. Fluorescein-loaded alginate microparticles prepared by VNM and emulsion phase inversion microencapsulation (EPIM) were lyophilized. Morphology, particle size distribution, lyophilized microspheres stability upon rehydration, drug loading and in vitro release were evaluated. Well-formed microspheres were obtained by the VNM technique, with higher yields of production (93.3-100%) and smaller particle size (d50138.10-158.00) than the EPIM microspheres. Rehydration upon lyophilization occurred in 30 min maintaining microsphere physical integrity. Fluorescein release was always faster from the microspheres obtained by VNM (364 h) than from those obtained by EPIM (504 h). The results suggest that VNM is a simple, easy to be scaled-up process suitable for the microencapsulation hydrophilic drugs.

  1. Development of lamellar gel phase emulsion containing marigold oil (Calendula officinalis) as a potential modern wound dressing.

    Science.gov (United States)

    Okuma, C H; Andrade, T A M; Caetano, G F; Finci, L I; Maciel, N R; Topan, J F; Cefali, L C; Polizello, A C M; Carlo, T; Rogerio, A P; Spadaro, A C C; Isaac, V L B; Frade, M A C; Rocha-Filho, P A

    2015-04-25

    Appropriate therapeutics for wound treatments can be achieved by studying the pathophysiology of tissue repair. Here we develop formulations of lamellar gel phase (LGP) emulsions containing marigold (Calendula officinalis) oil, evaluating their stability and activity on experimental wound healing in rats. LGP emulsions were developed and evaluated based on a phase ternary diagram to select the best LGP emulsion, having a good amount of anisotropic structure and stability. The selected LGP formulation was analyzed according to the intrinsic and accelerated physical stability at different temperatures. In addition, in vitro and in vivo studies were carried out on wound healing rats as a model. The LGP emulsion (15.0% marigold oil; 10.0% of blend surfactants and 75.0% of purified water [w/w/w]) demonstrated good stability and high viscosity, suggesting longer contact of the formulation with the wound. No cytotoxic activity (50-1000 μg/mL) was observed in marigold oil. In the wound healing rat model, the LGP (15 mg/mL) showed an increase in the leukocyte recruitment to the wound at least on days 2 and 7, but reduced leukocyte recruitment after 14 and 21 days, as compared to the control. Additionally, collagen production was reduced in the LGP emulsion on days 2 and 7 and further accelerated the process of re-epithelialization of the wound itself. The methodology utilized in the present study has produced a potentially useful formulation for a stable LGP emulsion-containing marigold, which was able to improve the wound healing process. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Attractive emulsion droplets probe the phase diagram of jammed granular matter.

    Science.gov (United States)

    Jorjadze, Ivane; Pontani, Lea-Laetitia; Newhall, Katherine A; Brujic, Jasna

    2011-03-15

    It remains an open question whether statistical mechanics approaches apply to random packings of athermal particles. Although a jamming phase diagram has recently been proposed for hard spheres with varying friction, here we use a frictionless emulsion system in the presence of depletion forces to sample the available phase space of packing configurations. Using confocal microscopy, we access their packing microstructure and test the theoretical assumptions. As a function of attraction, our packing protocol under gravity leads to well-defined jammed structures in which global density initially increases above random close packing and subsequently decreases monotonically. Microscopically, the fluctuations in parameters describing each particle, such as the coordination number, number of neighbors, and local packing fraction, are for all attractions in excellent agreement with a local stochastic model, indicating that long-range correlations are not important. Furthermore, the distributions of local cell volumes can be collapsed onto a universal curve using the predicted k-gamma distribution, in which the shape parameter k is fixed by the polydispersity while the effect of attraction is captured by rescaling the average cell volume. Within the Edwards statistical mechanics framework, this result measures the decrease in compactivity with global density, which represents a direct experimental test of a jamming phase diagram in athermal systems. The success of these theoretical tools in describing yet another class of materials gives support to the much-debated statistical physics of jammed granular matter.

  3. Transition from Spherical to Irregular Dispersed Phase in Water/Oil Emulsions

    NARCIS (Netherlands)

    Schmitt, M.; Limage, S.; Grigoriev, D.O.; Krägel, J.; Dutschk, Victoria; Vincent-Bonnieu, S.; Miller, R.; Antoni, M.

    2014-01-01

    Bulk properties of transparent and dilute water in paraffin oil emulsions stabilized with sodium dodecyl sulfate (SDS) are analyzed by optical scanning tomography. Each scanning shot of the considered emulsions has a precision of 1 mu m. The influence of aluminum oxide nanoparticles in the structure

  4. Air-filled polymeric microcapsules from emulsions containing different organic phases.

    Science.gov (United States)

    Bjerknes, K; Braenden, J U; Braenden, J E; Skurtveit, R; Smistad, G; Agerkvist, I

    2001-01-01

    Air-filled polymeric microcapsules for use as a contrast agent in ultrasonography have been prepared by the freeze-drying of different oil-in-water emulsions. The water phases consisted of a block copolymer in water. The organic phases consisted of a biodegradable polyester dissolved in (-)-camphene, cyclooctane, cyclohexane or tricyclene, which were relatively poor solvents for the polyester. A polymeric wall was, therefore, precipitated at the droplet surface early in the process, i.e. during freezing. Removing the solvent during freeze-drying, resulted in air-filled microcapsules. The microcapsules were suspended in saline after freeze-drying. All the suspensions contained echogenic microcapsules with a volume mean diameter of approximately 5-7 microm. Microscopic investigations showed that the microcapsules were spherical and hollow. Tricyclene and, to some degree, (-)-camphene were found unsuitable for industrial production due to melting points above 30 degrees C. Cyclooctane and cyclohexane were investigated as replacements for the initially chosen (-)-camphene, since they are liquids over a wider temperature range. These solvents gave improved yields, measured both as particle volume concentration per amount of polymer in suspension and acoustic attenuation at 3.5 MHz per amount of polymer in suspension, although the freeze-drying cycle was not optimized for these systems.

  5. Surfactant-enhanced cellulose nanocrystal Pickering emulsions.

    Science.gov (United States)

    Hu, Zhen; Ballinger, Sarah; Pelton, Robert; Cranston, Emily D

    2015-02-01

    The effect of surfactants on the properties of Pickering emulsions stabilized by cellulose nanocrystals (CNCs) was investigated. Electrophoretic mobility, interfacial tension, confocal microscopy and three-phase contact angle measurements were used to elucidate the interactions between anionic CNCs and cationic alkyl ammonium surfactants didecyldimethylammonium bromide (DMAB) and cetyltrimethylammonium bromide (CTAB). Both surfactants were found to adsorb onto CNCs with concentration-dependent morphology. At low concentrations, individual surfactant molecules adsorbed with alkyl tails pointing outward leading to hydrophobic CNCs. At higher concentrations, above the surfactant's apparent critical micelle concentration, surfactant aggregate morphologies on CNCs were inferred and the hydrophobicity of CNCs decreased. DMAB, which has two alkyl tails, rendered the CNCs more hydrophobic than CTAB which has only a single alkyl tail, at all surfactant concentrations. The change in CNC wettability from surfactant adsorption was directly linked to emulsion properties; adding surfactant increased the emulsion stability, decreased the droplet size, and controlled the internal phase of CNC Pickering emulsions. More specifically, a double transitional phase inversion, from oil-in-water to water-in-oil and back to oil-in-water, was observed for emulsions with CNCs and increasing amounts of DMAB (the more hydrophobic surfactant). With CNCs and CTAB, no phase inversion was induced. This work represents the first report of CNC Pickering emulsions with surfactants as well as the first CNC Pickering emulsions that can be phase inverted. The ability to surface modify CNCs in situ and tailor emulsions by adding surfactants may extend the potential of CNCs to new liquid formulations and extruded/spray-dried materials. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Room-temperature storage of microalgae in water-in-oil emulsions: influence of solid particle type and concentration in the oil phase.

    Science.gov (United States)

    Fernández, Lorena; Scher, Herbert; Jeoh, Tina; VanderGheynst, Jean S

    2015-12-01

    Water-in-oil emulsions containing silica nanoparticles (Aerosil R974) have the potential to stabilize microalgae for long-term storage. Studies were completed to determine if smectite clays could be used as an alternative to Aerosil R974. Emulsions were prepared with Aerosil R974, and hectorite and bentonite clays in the continuous phase and Chlorella sorokiniana was added to the aqueous phase to monitor the effects of solid particles on emulsion stability. Biological stability (cell viability) was determined using cell density measurements, and physical stability was measured from water droplet size distributions obtained by light scattering measurements and by examining phase separation over time. Measurements were also made to determine the effects of particles in the oil phase on emulsion viscosity. Particle concentrations greater than 0.25 wt% in the oil phase were required for maintaining physical stability. In emulsions containing 1 wt% solid particles and microalgae, biological stability of cells could be sustained for 340 days, regardless of particle type. At 1 wt% particles in the oil phase, apparent viscosity was 165% greater for samples containing hectorite and bentonite clays compared to samples containing Aerosil R974. The higher viscosity would need to be considered in large-scale production of emulsions for commercial application.

  7. Preparation of Paraffin@Poly(styrene-co-acrylic acid) Phase Change Nanocapsules via Combined Miniemulsion/Emulsion Polymerization.

    Science.gov (United States)

    Zhang, Feng; Liu, Tian-Yu; Hou, Gui-Hua; Guan, Rong-Feng; Zhang, Jun-Hao

    2018-06-01

    The fast development of solid-liquid phase change materials calls for nanomaterials with large specific surface area for rapid heat transfer and encapsulation of phase change materials to prevent potential leakage. Here we report a combined miniemulsion/emulsion polymerization method to prepare poly(styrene-co-acrylic acid)-encapsulated paraffin (paraffin@P(St-co-AA)) nanocapsules. The method could suppress the shortcomings of common miniemulsion polymerization (such as evaporation of monomer and decomposition of initiator during ultrasonication). The paraffin@P(St-co-AA) nanocapsules are uniform in size and the polymer shell can be controlled by the weight ratio of St to paraffin. The phase change behavior of the nanocapsules is similar to that of pure paraffin. We believe our method can also be utilized to synthesize other core-shell phase change materials.

  8. Preparation and characterization of nano-sized phase change emulsions as thermal energy storage and transport media

    International Nuclear Information System (INIS)

    Chen, J.; Zhang, P.

    2017-01-01

    Highlights: • The nano-sized phase change emulsions are prepared by using D-phase method. • The thermo-physical and transport properties are experimentally investigated. • The influence of surfactant on the melting temperature and latent heat of water is clarified. • The phase change emulsion can be used as the heat transfer fluid in a thermal energy storage system. - Abstract: Phase change emulsion (PCE) is a kind of two-phase heat transfer fluid with phase change material (PCM) dispersed in carrier fluid. It has received intensive attractions in recent years due to the fact that it can be used as both the thermal energy storage material and transport medium simultaneously in a thermal energy storage system. In the present study, nano-sized PCEs are prepared by the D-phase method with n-hexadecane and n-octadecane as PCMs. The thermo-physical and transport properties are characterized to facilitate the applications. The droplet size distribution of the PCE is measured by a Photon Correlation Spectroscopy, and the results show that the droplet size distributions are similar at different mass fractions. The rheological behavior and viscosity of the PCE are measured by a rheometer, which shows that the PCEs at mass fractions below 30.0 wt% are Newtonian fluids, and the viscosities are dependent on both the mass fraction and temperature. The differential scanning calorimetry (DSC) is employed to analyze the phase change characteristics of the PCE, and the results indicate large supercooling degree of water and PCM in the PCE. The melting temperature and latent heat of water in the PCE are much smaller than those of pure water. The thermal conductivities of the PCE with different mass fractions at different temperatures are measured by the transient hot-wire method. Furthermore, the energy transport characteristics of the PCEs are evaluated on the basis of the measured thermo-physical and transport properties. The results suggest that the PCEs show a drastic

  9. EFFECT OF MATRICES ON PERCENT EXTRACTION OF SILVER (II FROM BLACK/WHITE PRINTING PHOTOGRAPHIC WASTE USING EMULSION LIQUID MEMBRANE TECHNIQUE

    Directory of Open Access Journals (Sweden)

    Imam Santoso

    2010-06-01

    Full Text Available Extraction of silver (I has been studied from black/white printing photographic waste by emulsion liquid membrane technique. Composition emulsion at the membrane phase was cerosene as solvent, sorbitan monooleat (span 80 as surfactant, dimethyldioctadesyl-ammonium bromide as carrier and as internal phase was HNO3. Optimum condition was obtained: ratio of internal phase volume and membrane phase volume was 1:1 : concentration of surfactant was 2% (v/v : time of making emulsion was 20 second : rate of stiring emulsion was 1100 rpm : rest time emulsion was 3 second : rate of emulsion volume and external phase volume was 1:5 : emulsion contact rate 500 rpm : emulsion contact time was 40 second : concentration of silver thiosulfate as external phase was 100 ppm : pH of external phase was 3 and pH of internal phase was 1. Optimum condition was applied in silver(I extraction from black/white printing photographic waste. It was obtained 77.33% average which 56.06% silver (I average of internal phase and 22.66% in the external phase. Effect of matrices ion decreased silver(I percent extraction from 96,37% average to 77.33% average. Keyword: photographics waste, silver extraction

  10. Controllable microfluidic production of multicomponent multiple emulsions.

    Science.gov (United States)

    Wang, Wei; Xie, Rui; Ju, Xiao-Jie; Luo, Tao; Liu, Li; Weitz, David A; Chu, Liang-Yin

    2011-05-07

    A hierarchical and scalable microfluidic device constructed from a combination of three building blocks enables highly controlled generation of multicomponent multiple emulsions. The number, ratio and size of droplets, each with distinct contents being independently co-encapsulated in the same level, can be precisely controlled. The building blocks are a drop maker, a connector and a liquid extractor; combinations of these enable the scale-up of the device to create higher-order multicomponent multiple emulsions with exceptionally diverse structures. These multicomponent multiple emulsions offer a versatile and promising platform for precise encapsulation of incompatible actives or chemicals, for synergistic delivery and biochemical and chemical reactions, and for engineering multicompartment materials with controlled internal phases. © The Royal Society of Chemistry 2011

  11. Gas dispersion and bubble-to-emulsion phase mass exchange in a gas-solid bubbling fluidized bed: a computational and experimental study

    NARCIS (Netherlands)

    Patil, D.J.; van Sint Annaland, M.; Kuipers, J.A.M.

    2003-01-01

    Knowledge of gas dispersion and mass exchange between the bubble and the emulsion phases is essential for a correct prediction of the performance of fluidized beds, particularly when catalytic reactions take place. Test cases of single rising bubble and a bubbling fluidized bed operated with a jet

  12. Preparation and characterization of Phase change material microcapsules by a core-shell-like emulsion polymerization method

    Science.gov (United States)

    Ding, Li-ming; Pei, Guang-ling

    2015-07-01

    Phase change material microcapsules (MicroPCMs) were synthesized by a coreshell-like emulsion polymerization method. Styrene and methylacrylic acid copolymer (PS- MAA) was used as a wall material, and paraffin was used as a core material in order to prepare spherical, high resistance and high enthalpy MicroPCMs. Scanning Electron Microscope (SEM), laser particle size analyzer, Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetry (TG) and Differential Scanning Calorimeter (DSC) were employed to characterize the MicroPCMs. The results indicated that the average particle size of MicroPCMs was 42.29 μm, and the content of paraffin within microcapsules was 57.6%. The melting temperature and crystallization temperature were 30.7°C and 25.2°C.The melting enthalpy and crystallization enthalpy were -84.1 J/g and 91.3 J/g, respectively.

  13. Electrochemically driven emulsion inversion

    International Nuclear Information System (INIS)

    Johans, Christoffer; Kontturi, Kyoesti

    2007-01-01

    It is shown that emulsions stabilized by ionic surfactants can be inverted by controlling the electrical potential across the oil-water interface. The potential dependent partitioning of sodium dodecyl sulfate (SDS) was studied by cyclic voltammetry at the 1,2-dichlorobenzene|water interface. In the emulsion the potential control was achieved by using a potential-determining salt. The inversion of a 1,2-dichlorobenzene-in-water (O/W) emulsion stabilized by SDS was followed by conductometry as a function of added tetrapropylammonium chloride. A sudden drop in conductivity was observed, indicating the change of the continuous phase from water to 1,2-dichlorobenzene, i.e. a water-in-1,2-dichlorobenzene emulsion was formed. The inversion potential is well in accordance with that predicted by the hydrophilic-lipophilic deviation if the interfacial potential is appropriately accounted for

  14. Development of a membrane-assisted fluidized bed reactor - 1 - Gas phase back-mixing and bubble-to-emulsion phase mass transfer using tracer injection and ultrasound experiments

    NARCIS (Netherlands)

    Deshmukh, S.A.R.K.; Laverman, J.A.; Cents, A.H.G.; van Sint Annaland, M.; Kuipers, J.A.M.

    2005-01-01

    A small laboratory-scale membrane-assisted fluidized bed reactor (MAFBR) was constructed in order to experimentally demonstrate the benefits of this reactor concept, especially the enhanced bubble-to-emulsion phase mass transfer and the reduced overall axial gas phase back-mixing, due to the

  15. Phase behaviour and microstructure of the micro-emulsions composed of cholinium-based ionic liquid, Triton X-100 and water

    International Nuclear Information System (INIS)

    Pei, Yuanchao; Huang, Yanjie; Li, Lin; Wang, Jianji

    2014-01-01

    Highlights: • The microemulsions composed of cholinium-based ionic liquid, Triton X-100 and water have been prepared and characterised. • Ternary phase diagrams of the microemulsions have been established at T = 298.15 K. • The microemulsions exhibit IL-in-water, bicontinuous and water-in-IL microstructures. • Droplets with the size smaller than 20 nm are formed in these IL-based microemulsions. - Abstract: In this paper, micro-emulsions composed of cholinium-based ionic liquids (ILs), octylphenol ethoxylate (Triton X-100) and water were prepared. These ternary systems were found to be stable over 12 months at room temperature. Their phase behaviour was investigated by using cloud titrations, and their microstructures were characterised by means of cyclic voltammetry and electrical conductance measurements at T = 298.15 K. It was shown that the micro-emulsions exhibited IL-in-water, bi-continuous and water-in-IL microstructures. Dynamic light scattering data suggest that Triton X-100 forms micelles in water, which were swelled by the ILs added. Droplets with the size about 20 nm were formed in these IL-based micro-emulsions, and the droplet size increased with the increase of the IL concentrations. These IL-based micro-emulsions may have potential in drug delivery, chemical reactions and nanomaterial preparation as a new type of nanoreactors

  16. Fabrication of porous polymer microparticles with tunable pore size and density through the combination of phase separation and emulsion-solvent evaporation approach

    Science.gov (United States)

    Liu, Shanqin; Cai, Mingle; Deng, Renhua; Wang, Jianying; Liang, Ruijing; Zhu, Jintao

    2014-02-01

    A facile and versatile route to prepare porous polymer microparticles with tunable pore size and density through the combination of phase separation and emulsion-solvent evaporation method is demonstrated. When volatile organic solvent ( e.g., chloroform) diffuses through the aqueous phase containing poly(vinyl alcohol) (PVA) and evaporates, n-hexadecane (HD) and polystyrene (PS) in oil-in-water emulsion droplets occur to phase separate due to the incompatibility between PS and HD, ultimately yielding microparticles with porous structures. Interestingly, density of the pores (pore number) on the shell of microparticles can be tailored from one to hundreds by simply varying the HD concentration and/ or the rate of solvent evaporation. Moreover, this versatile approach for preparing porous microparticles with tunable pore size and density can be applied to other types of hydrophobic polymers, organic solvents, and alkanes, which will find potential applications in the fields of pharmaceutical, catalyst carrier, separation, and diagnostics.

  17. Combining Pickering Emulsion Polymerization with Molecular Imprinting to Prepare Polymer Microspheres for Selective Solid-Phase Extraction of Malachite Green

    Directory of Open Access Journals (Sweden)

    Weixin Liang

    2017-08-01

    Full Text Available Malachite green (MG is currently posing a carcinogenic threat to the safety of human lives; therefore, it is highly desirable to develop an effective method for fast trace detection of MG. Herein, for the first time, this paper presents a systematic study on polymer microspheres, being prepared by combined Pickering emulsion polymerization and molecular imprinting, to detect and purify MG. The microspheres, molecularly imprinted with MG, show enhanced adsorption selectivity to MG, despite a somewhat lowered adsorption capacity, as compared to the counterpart without molecular imprinting. Structural features and adsorption performance of these microspheres are elucidated by different characterizations and kinetic and thermodynamic analyses. The surface of the molecularly imprinted polymer microspheres (M-PMs exhibits regular pores of uniform pore size distribution, endowing M-PMs with impressive adsorption selectivity to MG. In contrast, the microspheres without molecular imprinting show a larger average particle diameter and an uneven porous surface (with roughness and a large pore size, causing a lower adsorption selectivity to MG despite a higher adsorption capacity. Various adsorption conditions are investigated, such as pH and initial concentration of the solution with MG, for optimizing the adsorption performance of M-PMs in selectively tackling MG. The adsorption kinetics and thermodynamics are deeply discussed and analyzed, so as to provide a full picture of the adsorption behaviors of the polymer microspheres with and without the molecular imprinting. Significantly, M-PMs show promising solid-phase extraction column applications for recovering MG in a continuous extraction manner.

  18. Dependence of the Internal Structure on Water/Particle Volume Ratio in an Amphiphilic Janus Particle-Water-Oil Ternary System: From Micelle-like Clusters to Emulsions of Spherical Droplets.

    Science.gov (United States)

    Noguchi, Tomohiro G; Iwashita, Yasutaka; Kimura, Yasuyuki

    2017-01-31

    Amphiphilic Janus particles (AJP), composed of hydrophilic and hydrophobic hemispheres, are one of the simplest anisotropic colloids, and they exhibit higher surface activities than particles with homogeneous surface properties. Consequently, a ternary system of AJP, water, and oil can form extremely stable Pickering emulsions, with internal structures that depend on the Janus structure of the particles and the system composition. However, the detail of these structures has not been fully explored, especially for the composition range where the amount of the minority liquid phase and AJP are comparable, where one would expect the Janus characteristics to be directly reflected. In this study, we varied the volume ratio of the particles and the minority liquid phase, water, by 2 orders of magnitude around the comparable composition range, and observed the resultant structures at the resolution of the individual particle dimensions by optical microscopy. When the volume ratio of water is smaller than that of the Janus particles, capillary interactions between the hydrophilic hemispheres of the particles induce micelle-like clusters in which the hydrophilic sides of the particles face inward. With increasing water content, these clusters grow into a rodlike morphology. When the water volume exceeds that of the particles, the structure transforms into an emulsion state composed of spherical droplets, colloidosomes, because of the surface activity of particles at the liquid-liquid interface. Thus, we found that a change in volume fraction alters the mechanism of structure formation in the ternary system, and large resulting morphological changes in the self-assembled structures reflect the anisotropy of the particles. The self-assembly shows essential commonalities with that in microemulsions of surfactant molecules, however the AJP system is stabilized only kinetically. Analysis of the dependence of the emulsion droplet size on composition shows that almost all the

  19. Water-in-oil Pickering emulsions stabilized by stearoylated microcrystalline cellulose.

    Science.gov (United States)

    Pang, Bo; Liu, Huan; Liu, Peiwen; Peng, Xinwen; Zhang, Kai

    2018-03-01

    Hydrophobic particles with static water contact angles larger than 90° are more like to stabilize W/O Pickering emulsions. In particular, high internal phase Pickering emulsions (HIPEs) are of great interest for diverse applications. However, W/O HIPEs have rarely been realized using sustainable biopolymers. Herein, we used stearoylated microcrystalline cellulose (SMCC) to stabilize W/O Pickering emulsions and especially, W/O HIPEs. Moreover, these W/O HIPEs can be further used as platforms for the preparation of porous materials, such as porous foams. Stearoylated microcrystalline cellulose (SMCC) was prepared by modifying MCC with stearoyl chloride under heterogeneous conditions. Using SMCC as emulsifiers, W/O medium and high internal phase Pickering emulsions (MIPEs and HIPEs) with various organic solvents as continuous phases were prepared using one-step and two-step methods, respectively. Polystyrene (PS) foams were prepared after polymerization of oil phase using HIPEs as templates and their oil/water separation capacity were studied. SMCC could efficiently stabilize W/O Pickering emulsions and HIPEs could only be prepared via the two-step method. The internal phase volume fraction of the SMCC-stabilized HIPEs reached as high as 89%. Diverse internal phase volume fractions led to distinct inner structures of foams with closed or open cells. These macroporous polystyrene (PS) foams demonstrated great potential for the effective absorption of organic solvents from underwater. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Emulsions for interfacial filtration.

    Energy Technology Data Exchange (ETDEWEB)

    Grillet, Anne Mary; Bourdon, Christopher Jay; Souza, Caroline Ann; Welk, Margaret Ellen; Hartenberger, Joel David; Brooks, Carlton, F.

    2006-11-01

    We have investigated a novel emulsion interfacial filter that is applicable for a wide range of materials, from nano-particles to cells and bacteria. This technology uses the interface between the two immiscible phases as the active surface area for adsorption of targeted materials. We showed that emulsion interfaces can effectively collect and trap materials from aqueous solution. We tested two aqueous systems, a bovine serum albumin (BSA) solution and coal bed methane produced water (CBMPW). Using a pendant drop technique to monitor the interfacial tension, we demonstrated that materials in both samples were adsorbed to the liquid-liquid interface, and did not readily desorb. A prototype system was built to test the emulsion interfacial filter concept. For the BSA system, a protein assay showed a progressive decrease in the residual BSA concentration as the sample was processed. Based on the initial prototype operation, we propose an improved system design.

  1. Use of the electrically-driven emulsion phase contactor in chemical and biochemical processing

    Energy Technology Data Exchange (ETDEWEB)

    Tsouris, C; DePaoli, D.W.; Scott, T.C.

    1995-12-31

    An electrically driven liquid-liquid contactor has been developed to enhance the efficiency of chemical and biochemical processes. A uniform electric field is utilized to induce a drop dispersion- coalescence cycle, producing high surface area for interfacial mass transfer under continuous-countercurrent-flow conditions. The mass- transport capability of this system has been analyzed by observing the extraction of acetic acid from water (dispersed phase) into methyl isobutyl ketone. Results showed that, due to increased efficiency of mass transfer, the electrically-driven device could be an order of magnitude smaller than a conventional contactor accomplishing the same level of separation. In the case of biochemical processes within non-aqueous environments, a biocatalyst (enzymes or bacteria) is introduced in the aqueous (dispersed) phase. The biocatalyst uses nutrients and other reactants to selectively transform species transferred from the continuous (organic) phase to the interior of the drops. An example of such system that has been investigated is the oxidation of p-cresol dissolved in toluene by aqueous-phase horseradish peroxidase.

  2. Emulsion Inks for 3D Printing of High Porosity Materials.

    Science.gov (United States)

    Sears, Nicholas A; Dhavalikar, Prachi S; Cosgriff-Hernandez, Elizabeth M

    2016-08-01

    Photocurable emulsion inks for use with solid freeform fabrication (SFF) to generate constructs with hierarchical porosity are presented. A high internal phase emulsion (HIPE) templating technique was utilized to prepare water-in-oil emulsions from a hydrophobic photopolymer, surfactant, and water. These HIPEs displayed strong shear thinning behavior that permitted layer-by-layer deposition into complex shapes and adequately high viscosity at low shear for shape retention after extrusion. Each layer was actively polymerized with an ultraviolet cure-on-dispense (CoD) technique and compositions with sufficient viscosity were able to produce tall, complex scaffolds with an internal lattice structure and microscale porosity. Evaluation of the rheological and cure properties indicated that the viscosity and cure rate both played an important role in print fidelity. These 3D printed polyHIPE constructs benefit from the tunable pore structure of emulsion templated material and the designed architecture of 3D printing. As such, these emulsion inks can be used to create ultra high porosity constructs with complex geometries and internal lattice structures not possible with traditional manufacturing techniques. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Sardine Fish Oil By Sentrifugation and Adsorbent for Emulsion

    OpenAIRE

    Kristina Haryati; Sugeng Heri Suseno; Nurjanah Nurjanah

    2017-01-01

    Sardine fish meal by-product contain eicosapentaenoic acid (EPA) and docosahexaenoic (DHA) and it can be made as emulsion. The purpose of this study were to determine the best fish oil emulsion by mixingthe oil phase (lecithin 3% and oil) and water phase (carboxymethyl cellulose/CMC 2% and fruit juice) and then stored until creaming, and the emulsion is analyzed their viscosity, pH, percent of stability and longseparation. Sardine oil is separated from the emulsion and tested oxidation parame...

  4. Preformulation studies on Freund's incomplete adjuvant emulsion.

    Science.gov (United States)

    Williams, R O; Mahaguna, V

    1998-02-01

    Freund's Incomplete Adjuvant (FIA), which is used in vaccine therapy, is a water-in-oil emulsion delivery system consisting of an aqueous internal phase containing an antigenic protein dispersed in an external phase containing a mixture of mannide monooleate and light mineral oil. Preformulation studies are reported in this investigation for FIA emulsion. The preformulation studies included the determination of the critical micelle concentration (CMC) of the formulations investigated, the surface activity of mannide monooleate at the interface between the oil phase and the aqueous phase containing ovalbumin as the model antigenic protein, and the effect of ovalbumin on the surface activity at the interface. The influence of the concentration of mannide monooleate and/or ovalbumin on the interfacial tension between light mineral oil and either purified water or 0.9% w/v normal saline solution was measured by the DuNouy Ring Method at 25 degrees C. The CMC was determined experimentally from the relationship between the concentration of the surface active agent in each formulation and the interfacial tension. The number of moles of the surface active agent per unit area at the interface (surface excess concentration) was calculated from the Gibbs' Adsorption equation. The results indicated that mannide monooleate was an effective surface active agent since the formulation containing only mannide monooleate provided the lowest magnitude of CMC. The presence of the surface active agent, mannide monooleate and/or ovalbumin, in the formulations studied reduced the interfacial tension between the two phases. The surface activity was influenced by the presence of an electrolyte (sodium chloride), a protein (ovalbumin), or mannide monooleate in the formulation. The presence of antigenic proteins in the aqueous phase of a waterin-oil emulsion influenced the effectiveness of a surface active agent in the formulation.

  5. Formulation and characterization of a multiple emulsion containing 1 ...

    African Journals Online (AJOL)

    The purpose of the study was to prepare a stable multiple emulsion containing a skin anti-aging agent and using paraffin oil. Vitamin C, was incorporated into the inner aqueous phase of water-in-oil-in-water (w/o/w) multiple emulsion at a concentration of 1%. Multiple emulsion was prepared by two step method. Stability ...

  6. Microcellular open porous polyester membranes from thiol-ene polymerisations of high internal phase emulsions

    Czech Academy of Sciences Publication Activity Database

    Sušec, M.; Paljevac, M.; Kotek, Jiří; Krajnc, P.

    2016-01-01

    Roč. 19, č. 6 (2016), s. 577-583 ISSN 1385-772X R&D Projects: GA MŠk(CZ) LO1507 Institutional support: RVO:61389013 Keywords : polymer membranes * mechanical properties * polyHIPE Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.139, year: 2016

  7. Highly concentrated emulsions. Physicochemical principles of the preparation and stability

    International Nuclear Information System (INIS)

    Babak, V G

    2008-01-01

    Theoretical and experimental studies on highly concentrated emulsions are critically analysed. The views on the relationship between the stability of surfactant-stabilised emulsions and the properties of microemulsion phases formed in surfactant-water-oil ternary systems are considered. The empirical criteria and rules that can be used to predict the type and stability of emulsions are presented. The physicochemical factors determining the rupture stability of emulsion films are discussed.

  8. Food emulsions as delivery systems for flavor compounds: A review.

    Science.gov (United States)

    Mao, Like; Roos, Yrjö H; Biliaderis, Costas G; Miao, Song

    2017-10-13

    Food flavor is an important attribute of quality food, and it largely determines consumer food preference. Many food products exist as emulsions or experience emulsification during processing, and therefore, a good understanding of flavor release from emulsions is essential to design food with desirable flavor characteristics. Emulsions are biphasic systems, where flavor compounds are partitioning into different phases, and the releases can be modulated through different ways. Emulsion ingredients, such as oils, emulsifiers, thickening agents, can interact with flavor compounds, thus modifying the thermodynamic behavior of flavor compounds. Emulsion structures, including droplet size and size distribution, viscosity, interface thickness, etc., can influence flavor component partition and their diffusion in the emulsions, resulting in different release kinetics. When emulsions are consumed in the mouth, both emulsion ingredients and structures undergo significant changes, resulting in different flavor perception. Special design of emulsion structures in the water phase, oil phase, and interface provides emulsions with great potential as delivery systems to control flavor release in wider applications. This review provides an overview of the current understanding of flavor release from emulsions, and how emulsions can behave as delivery systems for flavor compounds to better design novel food products with enhanced sensorial and nutritional attributes.

  9. High-Surface-Area, Emulsion-Templated Carbon Foams by Activation of polyHIPEs Derived from Pickering Emulsions

    Directory of Open Access Journals (Sweden)

    Robert T. Woodward

    2016-09-01

    Full Text Available Carbon foams displaying hierarchical porosity and excellent surface areas of >1400 m2/g can be produced by the activation of macroporous poly(divinylbenzene. Poly(divinylbenzene was synthesized from the polymerization of the continuous, but minority, phase of a simple high internal phase Pickering emulsion. By the addition of KOH, chemical activation of the materials is induced during carbonization, producing Pickering-emulsion-templated carbon foams, or carboHIPEs, with tailorable macropore diameters and surface areas almost triple that of those previously reported. The retention of the customizable, macroporous open-cell structure of the poly(divinylbenzene precursor and the production of a large degree of microporosity during activation leads to tailorable carboHIPEs with excellent surface areas.

  10. A programmable microenvironment for cellular studies via microfluidics-generated double emulsions.

    Science.gov (United States)

    Zhang, Ying; Ho, Yi-Ping; Chiu, Ya-Ling; Chan, Hon Fai; Chlebina, Ben; Schuhmann, Tom; You, Lingchong; Leong, Kam W

    2013-06-01

    High throughput cellular studies require small sample volume to reduce costs and enhance sensitivity. Microfluidics-generated water-in-oil (W/O) single emulsion droplet systems, in particular, provide uniform, well defined and discrete microenvironment for cell culture, screening, and sorting. However, these single emulsion droplets are incapable of continuous supply of nutrient molecule and are not compatible with aqueous phase-based analysis. A solution is to entrap W/O droplets in another aqueous phase, forming water-in-oil-in-water (W/O/W) double emulsions. The external aqueous phase efficiently prevents desiccation and reduces the amount of organic component, and yet retaining the advantages of compartmentalization. The internal environment can also be programmed dynamically without the need of rupturing the droplets. In this study, we explore the potential application of W/O/W double emulsion droplets for cell cultivation, genetic activation and study of more complicated biological events such as bacteria quorum-sensing as an example. This study demonstrates the advantages and potential application of double emulsion for the study of complex biological processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Emulsion Droplet Combustion in Microgravity: Water/Heptane Emulsions

    Science.gov (United States)

    Avedisian, C. Thomas

    1997-01-01

    This presentation reviews a series of experiments to further examine parametric effects on sooting processes of droplet flames in microgravity. The particular focus is on a fuel droplet emulsified with water, specifically emulsions of n-heptane as the fuel-phase and water as the dispersed phase. Water was selected as the additive because of its anticipated effect on soot formation, and the heptane fuel phase was chosen to theoretically reduce the likelihood of microexplosions because its boiling point is nearly the same as that of water: 100 C for water and 98 C for heptane. The water content was varied while the initial droplet diameter was kept within a small range. The experiments were carried out in microgravity to reduce the effects of buoyancy and to promote spherical symmetry in the burning process. Spherically symmetric droplet burning is a convenient starting point for analysis, but experimental data are difficult to obtain for this situation as evidenced by the fact that no quantitative data have been reported on unsupported emulsion droplet combustion in a convection-free environment. The present study improves upon past work carried out on emulsion droplet combustion in microgravity which employed emulsion droplets suspended from a fiber. The fiber can be instrusive to the emulsion droplet burning process as it can promote coalescence of the dispersed water phase and heterogeneous nucleation on the fiber. Prior work has shown that the presence of water in liquid hydrocarbons can have both beneficial and detrimental effects on the combustion process. Water is known to reduce soot formation and radiation heat transfer to combustor walls Gollahalli (1979) reduce flame temperatures and thereby NOx emissions, and encourage secondary droplet atomization or microexplosion. Water also tends to retard ignition and and promote early extinction. The former effect restricted the range of water volume fractions as discussed below.

  12. Transformation of eutectic emulsion to nanosuspension fabricating with solvent evaporation and ultrasonication technique.

    Science.gov (United States)

    Phaechamud, Thawatchai; Tuntarawongsa, Sarun

    2016-01-01

    Eutectic solvent can solubilize high amount of some therapeutic compounds. Volatile eutectic solvent is interesting to be used as solvent in the preparation of nanosuspension with emulsion solvent evaporation technique. The mechanism of transformation from the eutectic emulsion to nanosuspension was investigated in this study. The 30% w/w ibuprofen eutectic solution was used as the internal phase, and the external phase is composed of Tween 80 as emulsifier. Ibuprofen nanosuspension was prepared by eutectic emulsion solvent evaporating method followed with ultrasonication. During evaporation process, the ibuprofen concentration in emulsion droplets was increased leading to a drug supersaturation but did not immediately recrystallize because of low glass transition temperature (T g) of ibuprofen. The contact angle of the internal phase on ibuprofen was apparently lower than that of the external phase at all times of evaporation, indicating that the ibuprofen crystals were preferentially wetted by the internal phase than the external phase. From calculated dewetting value ibuprofen crystallization occurred in the droplet. Crystallization of the drug was initiated with external mechanical force, and the particle size of the drug was larger due to Ostwald ripening. Cavitation force from ultrasonication minimized the ibuprofen crystals to the nanoscale. Particle size and zeta potential of formulated ibuprofen nanosuspension were 330.87±51.49 nm and -31.1±1.6 mV, respectively, and exhibited a fast dissolution. Therefore, the combination of eutectic emulsion solvent evaporation method with ultrasonication was favorable for fabricating an ibuprofen nanosuspension, and the transformation mechanism was attained successfully.

  13. Mixed reverse micelles facilitated downstream processing of lipase involving water-oil-water liquid emulsion membrane.

    Science.gov (United States)

    Bhowal, Saibal; Priyanka, B S; Rastogi, Navin K

    2014-01-01

    Our earlier work for the first time demonstrated that liquid emulsion membrane (LEM) containing reverse micelles could be successfully used for the downstream processing of lipase from Aspergillus niger. In the present work, we have attempted to increase the extraction and purification fold of lipase by using mixed reverse micelles (MRM) consisting of cationic and nonionic surfactants in LEM. It was basically prepared by addition of the internal aqueous phase solution to the organic phase followed by the redispersion of the emulsion in the feed phase containing enzyme, which resulted in globules of water-oil-water (WOW) emulsion for the extraction of lipase. The optimum conditions for maximum lipase recovery (100%) and purification fold (17.0-fold) were CTAB concentration 0.075 M, Tween 80 concentration 0.012 M, at stirring speed of 500 rpm, contact time 15 min, internal aqueous phase pH 7, feed pH 9, KCl concentration 1 M, NaCl concentration 0.1 M, and ratio of membrane emulsion to feed volume 1:1. Incorporation of the nonionic surfactant (e.g., Tween 80) resulted in remarkable improvement in the purification fold (3.1-17.0) of the lipase. LEM containing a mixture of nonionic and cationic surfactants can be successfully used for the enhancement in the activity recovery and purification fold during downstream processing of enzymes/proteins. © 2014 American Institute of Chemical Engineers.

  14. A water-in-oil emulsion containing Kelex-100 for the speciation analysis of trace heavy metals in water

    International Nuclear Information System (INIS)

    Matsumiya, Hiroaki; Ohkouchi, Ryohei; Hiraide, Masataka

    2006-01-01

    A water-in-oil (w/o) emulsion containing Kelex-100 (7-dodecenyl-8-quinolinol) and Span-80 (sorbitan monooleate, non-ionic surfactant) was ultrasonically prepared from 1.0 mol l -1 hydrochloric acid and a (1 + 3) mixture of toluene and n-heptane. The resulting emulsion was gradually injected into water sample and dispersed as numerous tiny globules (0.01-0.1 mm in diameter). Dissolved inorganic species (free metal species) of heavy metals (e.g., Fe, Co, Cu, Cd, and Pb) were selectively transported through the oil layer into the internal aqueous phase of the emulsion, leaving other species, such as humic complexes and suspended particles (larger than 1 μm), in the sample solution. After collecting the dispersed emulsion globules, they were demulsified and the heavy metals in the segregated aqueous phase were determined by graphite-furnace atomic absorption spectrometry. The emulsion-based separation method allowed the selective collection of free metal species with a high concentration factor of 100, whereas the conventional solvent extraction did not offer such discrimination. This unique property of the emulsion method was successfully applied to the selective determination of free species of heavy metals in fresh water samples

  15. Extraction of uranium(VI) by emulsion liquid membrane containing 5,8-diethyl-7-hydroxy-6-dodecanone oxime

    International Nuclear Information System (INIS)

    Akiba, Kenichi; Takahashi, Toshihiko; Kanno, Takuji

    1984-01-01

    Extraction of uranium(VI) by a liquid surfactant membrane has been studied. The stability of water-in-oil (w/o) emulsion dispersed in the continuous aqueous phase increased with an increase in surfactant concentrations and in the fraction of the organic phase in emulsion globules. Uranium(VI) in dilute acid solutions was extracted into (w/o) emulsions containing 5,8-diethyl-7-hydroxy-6-dodecanone oxime (LIX 63) as a mobile carrier and its concentration decreased according to [U]sub(t)=[U]sub(o)exp(-ksub(obsd)t). The apparent rate constants (ksub(obsd)) increased with an increase in carrier concentrations and in external pH values, while they were slightly dependent on the stripping acid concentrations. Uranium was transported and concentrated into the internal aqueous droplets. The final concentration of uranium in the external aqueous phase dropped to about 10 -3 of its initial value. (author)

  16. International comparisons of Foundation Phase number domain ...

    African Journals Online (AJOL)

    Poor mathematics performance in schools is both a national and an international concern. Teachers ought to be equipped with relevant subject matter knowledge and pedagogical content knowledge as one way to address this problem. However, no mathematics knowledge and practice standards have as yet been defined ...

  17. Cultivate Africa's Future - Phase 2 | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    An International Organisation that is legally registered to operate in an eligible country can apply as an applicant organisation provided that the research team is based in the eligible countries, and the administration and management of the project, and contracting is done by the team that is based in the eligible country.

  18. Two phase exhaust for internal combustion engine

    Science.gov (United States)

    Vuk, Carl T [Denver, IA

    2011-11-29

    An internal combustion engine having a reciprocating multi cylinder internal combustion engine with multiple valves. At least a pair of exhaust valves are provided and each supply a separate power extraction device. The first exhaust valves connect to a power turbine used to provide additional power to the engine either mechanically or electrically. The flow path from these exhaust valves is smaller in area and volume than a second flow path which is used to deliver products of combustion to a turbocharger turbine. The timing of the exhaust valve events is controlled to produce a higher grade of energy to the power turbine and enhance the ability to extract power from the combustion process.

  19. Oxidative Stability and Shelf Life of Food Emulsions

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte

    2016-01-01

    Lipid oxidation and antioxidant effects in food emulsions are influenced by many different factors, such as the composition of the aqueous phase and interface, the partitioning of the antioxidants between the different phases of the emulsion system, the antioxidant properties, and others. This ch...

  20. Physical and antimicrobial properties of thyme oil emulsions stabilized by ovalbumin and gum arabic.

    Science.gov (United States)

    Niu, Fuge; Pan, Weichun; Su, Yujie; Yang, Yanjun

    2016-12-01

    Natural biopolymer stabilized oil-in-water emulsions were formulated using ovalbumin (OVA), gum arabic (GA) solutions and their complexes. The influence of interfacial structure of emulsion (OVA-GA bilayer and OVA/GA complexes emulsions) on the physical properties and antimicrobial activity of thyme oil (TO) emulsion against Escherichia coli (E. coli) was evaluated. The results revealed that the two types of emulsions with different oil phase compositions remained stable during a long storage period. The oil phase composition had an appreciable influence on the mean particle diameter and retention of the TO emulsions. The stable emulsion showed a higher minimum inhibitory concentration (MIC), and the TO emulsions showed an improved long-term antimicrobial activity compared to the pure thyme oil, especially complexes emulsion at pH 4.0. These results provided useful information for developing protection and delivery systems for essential oil using biopolymer. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Latest nuclear emulsion technology

    Science.gov (United States)

    Rokujo, Hiroki; Kawahara, Hiroaki; Komatani, Ryosuke; Morishita, Misaki; Nakano, Toshiyuki; Otsuka, Naoto; Yoshimoto, Masahiro

    2017-06-01

    Nuclear emulsion is a extremely high-resolution 3D tracking detector. Since the discovery of the pion by C.F. Powell et al. in 1946, experiments with nuclear emulsions have contributed to the development of particle physics. (e.g. the OPERA collaboration reported the discovery of νμ * ντ oscillations in appearance mode in 2015) The technology of nuclear emulsion still keeps making progress. Since 2010, we have introduced a system of nuclear emulsion gel production to our laboratory in Nagoya University, and have started self-development of the new gel, instead of from the photographic film companies. Moreover, a faster automated emulsion scanning system is developed. Its scanning speed reaches 4000 cm2/h, and the load for analyzing becomes more and more lighter. In this presentation, we report the status of nuclear emulsion technologies for cosmic ray experiments.

  2. Latest nuclear emulsion technology

    Directory of Open Access Journals (Sweden)

    Rokujo Hiroki

    2017-01-01

    Full Text Available Nuclear emulsion is a extremely high-resolution 3D tracking detector. Since the discovery of the pion by C.F. Powell et al. in 1946, experiments with nuclear emulsions have contributed to the development of particle physics. (e.g. the OPERA collaboration reported the discovery of νμ * ντ oscillations in appearance mode in 2015 The technology of nuclear emulsion still keeps making progress. Since 2010, we have introduced a system of nuclear emulsion gel production to our laboratory in Nagoya University, and have started self-development of the new gel, instead of from the photographic film companies. Moreover, a faster automated emulsion scanning system is developed. Its scanning speed reaches 4000 cm2/h, and the load for analyzing becomes more and more lighter. In this presentation, we report the status of nuclear emulsion technologies for cosmic ray experiments.

  3. Conditions for equilibrium solid-stabilized emulsions.

    Science.gov (United States)

    Kraft, Daniela J; de Folter, Julius W J; Luigjes, Bob; Castillo, Sonja I R; Sacanna, Stefano; Philipse, Albert P; Kegel, Willem K

    2010-08-19

    Particular types of solid-stabilized emulsions can be thermodynamically stable as evidenced by their spontaneous formation and monodisperse droplet size, which only depends on system parameters. Here, we investigate the generality of these equilibrium solid-stabilized emulsions with respect to the basic constituents: aqueous phase with ions, oil, and stabilizing particles. From systematic variations of these constituents, we identify general conditions for the spontaneous formation of monodisperse solid-stabilized emulsions droplets. We conclude that emulsion stability is achieved by a combination of solid particles as well as amphiphilic ions adsorbed at the droplet surface, and low interfacial tensions of the bare oil-water interface of order 10 mN/m or below. Furthermore, preferential wetting of the colloidal particles by the oil phase is necessary for thermodynamic stability. We demonstrate the sufficiency of these basic requirements by extending the observed thermodynamic stability to emulsions of different compositions. Our findings point to a new class of colloid-stabilized meso-emulsions with a potentially high impact on industrial emulsification processes due to the associated large energy savings.

  4. Macroporous polymer from core-shell particle-stabilized Pickering emulsions.

    Science.gov (United States)

    Li, Zifu; Ngai, To

    2010-04-06

    Poly(styrene-co-N-isopropylacrylamide) (PS-co-PNIPAM) core-shell particles were synthesized and used as particulate emulsifiers in the preparation of particle-stabilized (Pickering) emulsions. Highly concentrated oil-in-water emulsions with an internal phase up to 80 vol % can be produced using PS-co-PNIPAM core-shell particles along as the emulsifiers in emulsions. The core-shell particles are adsorbed at the liquid interface, acting as a barrier against oil droplet coalescence. In addition, it is likely that excess particles simultaneously form a gel in the continuous phase to trap oil droplets in the gel matrix, in turn inhibiting creaming and phase inversion. Evaporation in air of such a core-shell particle-stabilized emulsion directly leads to porous membranes in the absence of chemical reactions. The pore walls of the final structures are densely packed with layers of the core-shell particles. This provides great flexibility to prepare functionalized porous materials for opening up new applications.

  5. Study by nuclear magnetic resonance of deuterium (NMR 2H) of lyotropic phases initiators of 'micro emulsion' phases

    International Nuclear Information System (INIS)

    Latie, Laurence

    1988-01-01

    After a brief presentation of the pseudo-phases mode as an introduction to the lamellar phase of the ternary system (surfactant-co-surfactant-water) studied in this research thesis, and an explanation of the choice of deuterium nuclear magnetic resonance to perform this study, the author reports a study which aimed at a better knowledge of the membrane pseudo-phase structure. After a brief presentation of the different phases met in ternary systems, the author recalls the principles of deuterium NMR, and addresses the theory of exchange and its application to the studied systems. She presents experimental techniques, and presents, interprets and discusses the obtained results. She shows that NMR can be used to obtain a phase diagram, and to determine the exact structure of a membrane as well as its characterising constants [fr

  6. USE OF MEMBRANE EMULSION SPAN 80 AND TOPO IN URANIUM EXTRACTION AND STRIPPING

    Directory of Open Access Journals (Sweden)

    Kris Tri Basuki

    2017-01-01

    Full Text Available ABSTRACT USE OF MEMBRANE EMULSION SPAN 80 AND TOPO IN URANIUM EXTRACTION AND STRIPPING. Membrane emulsion span 80 and TOPO used in uranium extraction and stripping has been done. The extraction was carried outby emulsion membrane H3PO4 in TOPO-Kerosene. The feed or external aqueous phase was uranium in  HNO3. The emulgator span-80 was used to obtain a stable emulsion membrane system. The influence factors were percentage of TOPO-Kerosene, time extraction,  molarity of external aqueous phase and  molarity of internal aqueous. After the emulsion membrane was formed, the extractionand stripping process was performed. The ratio volume feed : volume membrane phase equal to 1 : 1 and volume of 5 % TOPO-Kerosene : Volume 3 M H3PO4 equal 1 : 1 were used. The relative good yield were obtained at concentration of TOPO in Kerosene and 3 M H3PO4 was 5 %, molarity of internal aqueous phase equal to 1 M, molarity of external aqueous phase 3 M H3PO4 and time extraction equalto 10 minutes with the speed of emulsification was 8000 rpm. At this condition the extraction efficiency of uranium obtained was 97.8 %, the stripping efficiency 52.56 %, and the total efficiency was 53.80 %. Keywords: membrane emulsion, extraction, stripping, span 80, kerosene, uranium. ABSTRAK PENGGUNAAN MEMBRAN EMULSI SPAN 80 DAN TOPO UNTUK EKSTRASI DAN STRIPPING URANIUM. Telah dilakukan penelitian membran emulsi span 80 dan TOPO yang digunakan untuk ekstraksi uranium. Extraksi dengan membran emulsi H3PO4 dalam TOPO-Kerosen. Larutan umpan untuk fasa air eksternal adalah uranium dalam asam nitrat. Untuk memperoleh sistem emulsi yang stabil dipakai emulgator Span 80. Parameter yang berpengaruh adalah persen TOPO-Kerosene, molaritas fasa air internal H3PO4, molaritas fasa air eksternal HNO3 dan waktu ekstraksi. Setelah diperoleh membran emulsi, kemudian dilakukan proses ekstraksi dan stripping, dengan rasio volume umpan : volume membran sebesar 1 : 1; volume 5% TOPO-Kerose : volume 3M

  7. Starch stabilized Pickering emulsions : Colloidal starch particles and their effects on emulsion properties

    OpenAIRE

    Saari, Hisfazilah

    2017-01-01

    Particles can be used to stabilize multi-phase systems known as Pickering emulsions. The aim of this thesis was to investigate how starch particles affect emulsion properties. Starch granules were used individually as well as in binary mixtures. To obtain a wide variety of starch properties granules were selected based on botanic variation (quinoa, oat, waxy barley, waxy maize and potato). The properties of the starch particles were furthermore changed by size fractionation by sedimentation, ...

  8. The international INTRAVAL project. Phase 2, Summary report

    International Nuclear Information System (INIS)

    Larsson, A.; Pers, K.; Skagius, K.; Dverstorp, B.

    1997-01-01

    The international project INTRAVAL addresses the validation of models of transport of radionuclides through groundwater in the geosphere. Such models are used in the assessment of the long-term safety of radioactive waste disposal systems. The second phase of INTRAVAL, which started in 1990, was concluded at the end of 1993. The objective of Phase 2 was to increase the understanding how various geophysical, geohydrological and geochemical phenomena of importance for radionuclide transport from a repository to the biosphere could be described by mathematical models and to study the model validation process. Summarized results from Phase 2 of the INTRAVAL study are presented in this report. (K.A.)

  9. Emulsion Science Basic Principles

    CERN Document Server

    Leal-Calderon, Fernando; Schmitt, Véronique

    2007-01-01

    Emulsions are generally made out of two immiscible fluids like oil and water, one being dispersed in the second in the presence of surface-active compounds.They are used as intermediate or end products in a huge range of areas including the food, chemical, cosmetic, pharmaceutical, paint, and coating industries. Besides the broad domain of technological interest, emulsions are raising a variety of fundamental questions at the frontier between physics and chemistry. This book aims to give an overview of the most recent advances in emulsion science. The basic principles, covering aspects of emulsions from their preparation to their destruction, are presented in close relation to both the fundamental physics and the applications of these materials. The book is intended to help scientists and engineers in formulating new materials by giving them the basics of emulsion science.

  10. TTI Phase 2 Institutional Support: REPOA | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The program aims to enhance their ability to provide sound research that informs and influences policy. This second TTI phase (2014?2019) will fund 43 institutions. This will help them consolidate their role as credible development actors in their countries, and in some cases, regionally and internationally. For REPOA, this ...

  11. Removal of Radioactive Pollutants by Liquid Emulsion Membrane From Liquid Waste

    International Nuclear Information System (INIS)

    Yossef, Y.A.A.

    2013-01-01

    Radioactive liquid waste should be safely managed because it is potentially hazardous to human health and the environment. Several methods were used for treatment of liquid waste, such as liquid emulsion membrane (LEM). In this work, liquid emulsion membrane using Tri-butyl phosphate (TBP) plus Bis (2-ethylhexyl) phosphate (HDEHP) as mobile carriers, hydrochloric acid (HCl) as stripping agents and an emulsifying agent (span 80) was used for the extraction of uranium ions from radioactive liquid waste. Various parameters influencing the permeation of uranium ions through the membrane have been optimized to separate uranium ions from radioactive liquid waste such as: the effects of membrane material, carrier concentration, operating conditions, etc. were examined; moreover, the transport mechanism of this uranium was also studied. The internal mass transfer in the water/oil (W/O) emulsion drop, the external mass transfer around the drop, the rates of formation, and the decomposition of the complex at the external aqueous-organic interface were considered. The results show that, the liquid emulsion membrane which consists of (25% by volume HDEHP, 0.005 M + 75% by volume TBP, 0.01 M) as extractant (carrier), span 80, 4% (v/v) (sorbitan monooleate) as surfactant agent, hydrochloric acid (HCl), (1.0 M) as stripping agent. From the results, the maximum extraction percent of uranium ions (nearly about of 100%) occurred at the operating conditions: stirring speed =500 rpm, the ratio between LEM and feed phase (liquid waste) = 20 ml: 100 ml, the ratio between organic phase (membrane phase) to internal aqueous phase (stripping phase) = 1.0 and the ph value of the external aqueous phase equal to 5.0.

  12. 17th International Conference on Petroleum Phase Behavior and Fouling

    DEFF Research Database (Denmark)

    von Solms, Nicolas; Yan, Wei; Andersen, Simon

    2017-01-01

    This special section of Energy & Fuels contains contributedpapers from the 17th International Conference on PetroleumPhase Behavior and Fouling (Petrophase 2016). Petrophase 2016 was organized by the Technical University of Denmark and Schlumberger and took place in Elsinore (Helsingør) Denmark...... from June 19th to 23rd at the Beach Hotel Marienlyst. Petrophase is an international conference aimed at researchers in industry and academia dedicated to the study of the properties and chemistry of petroleum fluids and their effect on producing, processing, and refining in the upstream, midstream......, and downstream industries. The conference started in 1999 as “The International Conference on Petroleum Phase Behavior & Fouling” and has since evolved into an annual event taking place in countries all around the world. Petrophase has been fortunate to have enjoyed financial and organizational support from many...

  13. Ultrasonic Studies of Emulsion Stability in the Presence of Magnetic Nanoparticles

    OpenAIRE

    Józefczak, A.; Wlazło, R.

    2015-01-01

    Pickering emulsions are made of solid particle-stabilized droplets suspended in an immiscible continuous liquid phase. A magnetic emulsion can be obtained using magnetic particles. Solid magnetic nanoparticles are adsorbed strongly at the oil-water interface and are able to stabilize emulsions of oil and water. In this work emulsions stabilized by magnetite nanoparticles were obtained using high-energy ultrasound waves and a cavitation mechanism and, next, their stability in time was tested b...

  14. International Before Commercial: Investigating the Pre-Commercial Phase of International New Ventures

    Directory of Open Access Journals (Sweden)

    Nicolai Løvdal

    2013-03-01

    Full Text Available In this study we focus newly established companies within the wave and tidal energy industry. Companies in this industry have not yet reached the phase of commercial production and sales. Our study investigates presents three case companies, analyzing their development pattern and how they access resources through international activities in the pre-commercial phase. The results reveal extensive international activities, were the companies seek for and exploits resources from a variety of countries even the early phases of their development. In fact, they are willing to establish large part of their activities in foreign countries (and even move their home base to access resources. A key implication for managers is the need of balancing international use of resources and international access to resources. From the perspective of policy makers, the case study illustrate how countries and regions compete in order to attract the attention from and activity of firms in an emerging industry. These companies relocate activity across borders depending on the support framework offered. For researchers, the study demonstrates the need of focus on the international dimension of firm activity as early as in the pre-commercial phase.

  15. Phytonadione Content in Branded Intravenous Fat Emulsions.

    Science.gov (United States)

    Forchielli, Maria Luisa; Conti, Matteo; Motta, Roberto; Puggioli, Cristina; Bersani, Germana

    2017-03-01

    Intravenous fat emulsions (IVFE) with different fatty acid compositions contain vitamin E as a by-product of vegetable and animal oil during the refining processes. Likewise, other lipid-soluble vitamins may be present in IVFE. No data, however, exist about phytonadione (vitamin K1) concentration in IVFE information leaflets. Therefore, our aim was to evaluate the phytonadione content in different IVFE. Analyses were carried out in triplicate on 6 branded IVFE as follows: 30% soybean oil (100%), 20% olive-soybean oil (80%-20%), 20% soybean-medium-chain triglycerides (MCT) coconut oil (50%-50%), 20% soybean-olive-MCT-fish oil (30%-25%-30%-15%), 20% soybean-MCT-fish oil (40%-50%-10%), and 10% pure fish oil (100%). Phytonadione was analyzed and quantified by a quali-quantitative liquid chromatography-mass spectrometry (LC-MS) method after its extraction from the IVFE by an isopropyl alcohol-hexane mixture, reverse phase-liquid chromatography, and specific multiple-reaction monitoring for phytonadione and vitamin d3 (as internal standard). This method was validated through specificity, linearity, and accuracy. Average vitamin K1 content was 500, 100, 90, 100, 95, and 70 µg/L in soybean oil, olive-soybean oil, soybean-MCT coconut oil, soybean-olive-MCT-fish oil, soybean-MCT-fish oil, and pure fish oil intravenous lipid emulsions (ILEs), respectively. The analytical LC-MS method was extremely effective in terms of specificity, linearity ( r = 0.99), and accuracy (coefficient of variation <5%). Phytonadione is present in IVFE, and its intake varies according to IVFE type and the volume administered. It can contribute to daily requirements and become clinically relevant when simultaneously infused with multivitamins during long-term parenteral nutrition. LC-MS seems adequate in assessing vitamin K1 intake in IVFE.

  16. Emulsions inside Gargamelle

    CERN Multimedia

    1978-01-01

    A feasibility test was made with a 2.5 litre emulsion stack installed within the chamber. The stack was contained in a thermally insulated aluminium alloy pressure vessel (photo). See Annual Report 1978 p. 79 Fig. 5.

  17. Polymerization in emulsion microdroplet reactors

    Science.gov (United States)

    Carroll, Nick J.

    The goal of this research project is to utilize emulsion droplets as chemical reactors for execution of complex polymerization chemistries to develop unique and functional particle materials. Emulsions are dispersions of immiscible fluids where one fluid usually exists in the form of drops. Not surprisingly, if a liquid-to-solid chemical reaction proceeds to completion within these drops, the resultant solid particles will possess the shape and relative size distribution of the drops. The two immiscible liquid phases required for emulsion polymerization provide unique and complex chemical and physical environments suitable for the engineering of novel materials. The development of novel non-ionic fluorosurfactants allows fluorocarbon oils to be used as the continuous phase in a water-free emulsion. Such emulsions enable the encapsulation of almost any hydrocarbon compound in droplets that may be used as separate compartments for water-sensitive syntheses. Here, we exemplify the promise of this approach by suspension polymerization of polyurethanes (PU), in which the liquid precursor is emulsified into droplets that are then converted 1:1 into polymer particles. The stability of the droplets against coalescence upon removal of the continuous phase by evaporation confirms the formation of solid PU particles. These results prove that the water-free environment of fluorocarbon based emulsions enables high conversion. We produce monodisperse, cross-linked, and fluorescently labeled PU-latexes with controllable mesh size through microfluidic emulsification in a simple one-step process. A novel method for the fabrication of monodisperse mesoporous silica particles is presented. It is based on the formation of well-defined equally sized emulsion droplets using a microfluidic approach. The droplets contain the silica precursor/surfactant solution and are suspended in hexadecane as the continuous oil phase. The solvent is then expelled from the droplets, leading to

  18. New apparatus for liquid-liquid extraction, 'emulsion flow' extractor

    International Nuclear Information System (INIS)

    Yanase, Nobuyuki; Naganawa, Hirochika; Nagano, Tetsushi; Noro, Junji

    2011-01-01

    A simple and low-cost apparatus for continuous and efficient liquid-liquid extraction, which does not need continual mechanical forces (stirring, shaking, etc.) other than solution sending, has newly been developed. This apparatus, named 'emulsion flow' extractor, is composed of a column part where an emulsified state fluid flow (emulsion flow) is generated by spraying micrometer-sized droplets of an aqueous phase into an organic phase and a phase-separating part where the emulsion flow is destabilized by means of a sudden decrease in its vertical liner velocity due to a drastic increase in cross-section area of the emulsion flow passing through. In the present study, the performance of a desktop emulsion flow extractor in the extraction of Yb(III) and U(VI) from aqueous HNO 3 solutions into isooctane containing bis(2-ethylhexyl) phosphoric acid (D2EHPA) was evaluated. The mixing efficiency of the emulsion flow extractor was found to be comparable with that of a popular liquid-liquid extractor, mixer-settler. Moreover, the emulsion flow extractor proved to have an overwhelming advantage in terms of phase-separating ability. (author)

  19. NARCOSIS AND EMULSION REVERSAL BY INERT GASES

    Science.gov (United States)

    Sears, Dewey F.; Fenn, Wallace O.

    1957-01-01

    Investigations of the effect of high pressures of Na (100 to 130 atmospheres) and of Ar (60 to 80 atmospheres) showed that these gases are effective in reversing the phases of an oil in water emulsion. Nitrous oxide did not cause reversal at pressures as high as 53 atmospheres nor did helium as high as 107 atmospheres. We found CO2 most effective in reversing the emulsions and attributed this to its chemical properties. It is suggested that these observations may help to explain the narcotic effects of inert gases. PMID:13416527

  20. Carboxymethylated lignins with low surface tension toward low viscosity and highly stable emulsions of crude bitumen and refined oils.

    Science.gov (United States)

    Li, Shuai; Ogunkoya, Dolanimi; Fang, Tiegang; Willoughby, Julie; Rojas, Orlando J

    2016-11-15

    Kraft and organosolv lignins were subjected to carboxymethylation to produce fractions that were soluble in water, displayed a minimum surface tension as low as 34mN/m (25°C) and a critical aggregation concentration of ∼1.5wt%. The carboxymethylated lignins (CML), which were characterized in terms of their degree of substitution ((31)P NMR), elemental composition, and molecular weight (GPC), were found suitable in the formulation of emulsions with bitumens of ultra-high viscosity, such as those from the Canadian oil sands. Remarkably, the interfacial features of the CML enabled fuel emulsions that were synthesized in a very broad range of internal phase content (30-70%). Cryo-replica transmission electron microscopy, which was used here the first time to assess the morphology of the lignin-based emulsions, revealed the droplets of the emulsion stabilized with the modified lignin. The observed drop size (diametersoil) that enabled operation of a fuel engine. A significant finding is that under certain conditions and compared to the respective pure fuel, combustion of the O/W emulsions stabilized by CML presented lower NOx and CO emissions and maintained a relatively high combustion efficiency. The results highlight the possibilities in high volume application for lignin biomacromolecules. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. 4-nitrophenol removal from aqueous solutions by emulsion liquid membranes using type I facilitation.

    Science.gov (United States)

    León, G; Guzmán, M A; Miguel, B

    2013-01-01

    Nitrophenols are common organic pollutants that enter the environment during the manufacture and processing of a variety of industrial products. The removal of 4-nitrophenol (4NP) from aqueous solutions by emulsion liquid membranes using the type I facilitated transport mechanism is investigated in this paper. The liquid membrane consisted of kerosene as the organic diluent, sorbitan monooleate as the emulsifying agent and sodium hydroxide as the stripping agent. The most important operational variables governing the emulsion stability and the 4NP removal process--such as the stripper agent and surfactant concentrations, the volume ratios of membrane phase/internal phase and emulsion phase/feed phase and stirring speed - were studied and the optimal conditions of the removal process were experimentally determined. Apparent initial permeabilities of the transport process in the different operational conditions were also obtained. Ninety-eight per cent of4NP was removed in 10 minutes and an apparent initial permeability of 1.2986 min(-1) was obtained in those optimal conditions.

  2. Emulsion analysis in the OPERA experiment

    International Nuclear Information System (INIS)

    Naganawa, N

    2010-01-01

    OPERA is a unique experiment aimed at the first detection of ν τ appearance in a flux of ν μ due to the neutrino oscillation from ν μ to ν τ . The CERN CNGS beam is the source of ν μ . The detector is hybrid; it is composed of nuclear emulsion films and electronic detectors. It is located in the LNGS underground laboratory. The target consists of 150,000 Emulsion Cloud Chambers (ECC) bricks, which are stacks of interleaved emulsion films and lead plates. The ν τ charged current interactions will be detected by identifying the decay topology of the τ in the ECC bricks. The first run started in 2008. The experiment is currently in the phase of data taking and analysis. The experimental methods, the status and the summary of the results from the 2008 run are presented in this paper.

  3. High pressure inactivation of Clostridium botulinum type E endospores in model emulsion systems

    Science.gov (United States)

    Schnabel, Juliane; Lenz, Christian A.; Vogel, Rudi F.

    2015-01-01

    Clostridium botulinum type E is a cold-tolerant, neurotoxigenic, endospore-forming organism, primarily associated with aquatic environments. High pressure thermal (HPT) processing presents a promising tool to enhance food safety and stability. The effect of fat on HPT inactivation of C. botulinum type E spores was investigated using an emulsion model system. The distribution of spores in oil-in-water (O/W) emulsions and their HPT (300-750 MPa, 45-75 °C, 10 min) inactivation was determined as a function of emulsion fat content (30-70% (v/v) soybean oil in buffer). Approximately 26% and 74% of the spores were located at the oil-buffer interface and the continuous phase, respectively. Spore inactivation in emulsion systems decreased with increasing oil contents, which suggests that the fat content of food plays an important role in the protection of C. botulinum type E endospores against HPT treatments. These results can be helpful for future safety considerations. This paper was presented at the 8th International Conference on High Pressure Bioscience & Biotechnology (HPBB 2014), in Nantes (France), 15-18 July 2014.

  4. Physical Stability of Whippable Oil-in-Water Emulsions

    DEFF Research Database (Denmark)

    Munk, Merete Bøgelund

    Whippable emulsions based on vegetable fat are increasingly used as replacement for dairy whipping creams. One of the quality criteria of whippable emulsions is that it should be low-viscous prior to whipping, but sudden viscosity increase or even solidification during storage and transport...... despite appliance of shear and temperature changes from 5 to 20 °C. Globule aggregation induced by LACTEM was impeded when used in combination with GMS. On the contrary, GMU induced very dense fat globule networks in emulsions which transformed emulsions into very firm solid-like pastes. This effect...... instability in emulsions, and conversely physical instability was not necessarily accompanied by protein displacement. GMS and LACTEM efficiently displaced caseinate from the fat globule interface into the serum phase, while caseinate molecules remained partly attached to the interfacial globule layer...

  5. Fabrication and Properties of Micro-Nanoencapsulated Phase Change Materials for Internally-Cooled Liquid Desiccant Dehumidification.

    Science.gov (United States)

    Niu, Xiaofeng; Xu, Qing; Zhang, Yi; Zhang, Yue; Yan, Yufeng; Liu, Tao

    2017-04-29

    Micro-nanoencapsulated phase change materials (M-NEPCMs) are proposed to be useful in liquid desiccant dehumidification by restraining the temperature rise in the moisture-removal process and improving the dehumidification efficiency. In this paper, the n -octadecane M-NEPCMs with desirable thermal properties for internally-cooled dehumidification were fabricated by using compound emulsifiers through the in-situ polymerization method. Melamine-formaldehyde resin was used as the shell material. The effects of the mixing ratio, emulsification methods and amount of the compound emulsifiers on the morphology, size and thermal properties of the M-NEPCMs were investigated experimentally. The optimum weight mixing ratio of the compound emulsifiers is SDS (sodium dodecyl sulfate):Tween80 (polyoxyethylene sorbitan monooleate):Span80 (sorbitan monooleate) = 0.1:0.6:0.3, which achieves the best stability of the n -octadecane emulsion. When the compound emulsifiers are 10 wt. % of the core material, the melting enthalpy of M-NEPCMs reaches its maximum of 145.26 J/g of capsules, with an encapsulation efficiency of 62.88% and a mean diameter of 636 nm. The sub-cooling of the prepared M-NEPCMs is lower than 3 °C, with an acceptable thermal reliability after the thermal cycling test. A pre-emulsification prior to the addition of deionized water in the emulsification is beneficial to the morphology of the capsules, as the phase change enthalpy can be increased by 123.7%.

  6. Polyaniline Nanofibers: Their Amphiphilicity and Uses for Pickering Emulsions and On-Demand Emulsion Separation.

    Science.gov (United States)

    Zhou, Ping; Li, Jing; Yang, Wenwen; Zhu, Lihua; Tang, Heqing

    2018-02-27

    The wetting property of nanomaterials is of great importance to both fundamental understanding and potential applications. However, the study on the intrinsic wetting property of nanomaterials is interfered by organic capping agents, which are often used to lower the surface energy of nanomaterials and avoid their irreversible agglomeration. In this work, the wetting property of the nanostructured polyaniline that requires no organic capping agents is investigated. Compared to hydrophilic granular particulates, polyaniline nanofibers are amphiphilic and have an excellent capability of creating Pickering emulsions at a wide range of pH. It is suggested that polyaniline nanofibers can be easily wetted by water and oil. Furthermore, the amphiphilic polyaniline nanofibers as building blocks can be used to construct filtration membranes with a small pore size. The wetting layer of the continuous phase of emulsions in the porous nanochannels efficiently prevents the permeation of the dispersed phase, realizing high-efficiency on-demand emulsion separation.

  7. Crocin loaded nano-emulsions: Factors affecting emulsion properties in spontaneous emulsification.

    Science.gov (United States)

    Mehrnia, Mohammad-Amin; Jafari, Seid-Mahdi; Makhmal-Zadeh, Behzad S; Maghsoudlou, Yahya

    2016-03-01

    Spontaneous emulsification may be used for encapsulating bioactive compounds in food and pharmaceutical industry. It has several advantages over high energy and other low energy methods including, protecting sensitive compounds against severe conditions of high energy method and its ability to minimize surfactant, removal of cosurfactant and thermal stability compared with other low energy methods. In this study, we examined possibility of encapsulating highly soluble crocin in W/O micro-emulsions using spontaneous method which further could be used for making double emulsions. Nonionic surfactants of Span 80 and polyglycerol polyricinoleate (PGPR) were used for making micro-emulsions that showed the high potential of PGPR for spontaneous method. Surfactant to water ratio (SWR%) was evaluated to find the highest amount of aqueous phase which can be dispersed in organic phase. Droplet size decreased by increasing SWR toward the SWR=100% which had the smallest droplet size and then increased at higher levels of surfactant. By increasing SWR, shear viscosity increased which showed the high effect of PGPR on rheological properties. This study shows in addition to W/O micro-emulsions, spontaneous method could be used for preparing stable O/W micro-emulsions. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Perfluorocarbon (PFC) emulsions as potential drug carriers

    International Nuclear Information System (INIS)

    Yuhas, J.M.; Goodman, R.L.; Moore, R.E.

    1984-01-01

    PFC emulsions have excellent oxygen transporting properties and have been reported to enhance the response of murine tumors to both radiation and BCNU. While the presently available emulsions are far too toxic to the immune system to be used in cancer therapy, they can be used to investigate the overall potential of this approach. As an example, the authors have found that these emulsions can alter drug availability. The lipophilicity of both the PFC and the drug in question determine the partitioning of the drug between the organic and aqueous phases of an emulsion. In vitro, this can reduce drug effectiveness by reducing the amount of drug available to the cells. In vivo, however, this partitioning may produce sustained drug exposure, which could be of benefit in cancer therapy and other applications. In brief, as the drug is absorbed from the circulating aqueous phase, additional drug would leach from the PFC, thereby providing a sustained drug exposure similar to that obtained with liposomes. While a great deal more work will be required to evaluate the practicality of this approach, the existence of this phenomenon must be taken into account in both the design and interpretation of efficacy studies in which anesthetics, chemotherapeutics, etc are employed

  9. Study on Mg2+ removal from ammonium dihydrogen phosphate solution by an emulsion liquid membrane

    Directory of Open Access Journals (Sweden)

    Luo JianHong

    2014-01-01

    Full Text Available Mg2+is extracted from ammonium dihydrogen phosphate (NH4H2PO4 solution by an emulsion liquid membrane (ELM using mono-(2-ethylhexyl 2-ethylhexyl phosphonate (HEHPEHEas a carrier, sulfonated liquid polybutadiene (LYF as a surfactant and kerosene as a solvent. To study the extraction efficiency and advantages of the ELM process in the separation of Mg2+,the effects of various operating conditions on the extraction -HEHPEHE volume fraction, reaction temperature, treat ratio (emulsion phase / external phase, phase ratio (membrane phase / internal phase, agitation speed, extraction time, internal phase concentration, surfactant LYF concentration and initial pH of NH4H2PO4 solution are experimentally investigated and discussed. The results show that Mg2+ in NH4H2PO4 solution can be effectively removed by the ELM process. An extraction efficiency of more than 83.1% is attained at the optimized parameters and superior-grade NH4H2PO4can be obtained by two levels of extraction.

  10. Development of High Sensitivity Nuclear Emulsion and Fine Grained Emulsion

    Science.gov (United States)

    Kawahara, H.; Asada, T.; Naka, T.; Naganawa, N.; Kuwabara, K.; Nakamura, M.

    2014-08-01

    Nuclear emulsion is a particle detector having high spacial resolution and angular resolution. It became useful for large statistics experiment thanks to the development of automatic scanning system. In 2010, a facility for emulsion production was introduced and R&D of nuclear emulsion began at Nagoya university. In this paper, we present results of development of the high sensitivity emulsion and fine grained emulsion for dark matter search experiment. Improvement of sensitivity is achieved by raising density of silver halide crystals and doping well-adjusted amount of chemicals. Production of fine grained emulsion was difficult because of unexpected crystal condensation. By mixing polyvinyl alcohol (PVA) to gelatin as a binder, we succeeded in making a stable fine grained emulsion.

  11. Development of High Sensitivity Nuclear Emulsion and Fine Grained Emulsion

    Energy Technology Data Exchange (ETDEWEB)

    Kawahara, H.; Asada, T. [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Naka, T. [Institute of Advanced Research, Nagoya University (Japan); Naganawa, N.; Kuwabara, K.; Nakamura, M. [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)

    2014-08-15

    Nuclear emulsion is a particle detector having high spacial resolution and angular resolution. It became useful for large statistics experiment thanks to the development of automatic scanning system. In 2010, a facility for emulsion production was introduced and R and D of nuclear emulsion began at Nagoya university. In this paper, we present results of development of the high sensitivity emulsion and fine grained emulsion for dark matter search experiment. Improvement of sensitivity is achieved by raising density of silver halide crystals and doping well-adjusted amount of chemicals. Production of fine grained emulsion was difficult because of unexpected crystal condensation. By mixing polyvinyl alcohol (PVA) to gelatin as a binder, we succeeded in making a stable fine grained emulsion.

  12. Ultrasonic Studies of Emulsion Stability in the Presence of Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    A. Józefczak

    2015-01-01

    Full Text Available Pickering emulsions are made of solid particle-stabilized droplets suspended in an immiscible continuous liquid phase. A magnetic emulsion can be obtained using magnetic particles. Solid magnetic nanoparticles are adsorbed strongly at the oil-water interface and are able to stabilize emulsions of oil and water. In this work emulsions stabilized by magnetite nanoparticles were obtained using high-energy ultrasound waves and a cavitation mechanism and, next, their stability in time was tested by means of acoustic waves with a low energy, without affecting the structure. An acoustic study showed high stability in time of magnetic emulsions stabilized by magnetite particles. The study also showed a strong influence of an external magnetic field, which can lead to changes of the emulsion properties. It is possible to control Pickering emulsion stability with the help of an external stimulus—a magnetic field.

  13. Pickering emulsions stabilized by coloured organic pigment particles.

    Science.gov (United States)

    Binks, Bernard P; Olusanya, Samuel O

    2017-01-01

    The possibility of stabilizing emulsions of water and non-polar alkane with pure, coloured organic pigment particles is explored. Seven pigment types each possessing a primary colour of the rainbow were selected. Their solubility in water or heptane was determined using a spectrophotometric method and their surface energies were derived from the contact angles of probe liquids on compressed disks of the particles. As expected, most of the pigments are relatively hydrophobic but pigment orange is quite hydrophilic. At equal volumes of oil and water, preferred emulsions were water-in-oil (w/o) for six pigment types and oil-in-water (o/w) for pigment orange. The emulsion type is in line with calculated contact angles of the particles at the oil-water interface being either side of 90°. Their stability to coalescence increases with particle concentration. Emulsions are shown to undergo limited coalescence from which the coverage of drop interfaces by particles has been determined. In a few cases, close-packed primary particles are visible around emulsion droplets. At constant particle concentration, the influence of the volume fraction of water ( φ w ) on emulsions was also studied. For the most hydrophilic pigment orange, emulsions are o/w at all φ w , whereas they are w/o for the most hydrophobic pigments (red, yellow, green and blue). For pigments of intermediate hydrophobicity however (indigo and violet), catastrophic phase inversion becomes possible with emulsions inverting from w/o to o/w upon increasing φ w . For the first time, we link the pigment surface energy to the propensity of emulsions to phase invert transitionally or catastrophically.

  14. Abstracts of the 9. annual international conference on petroleum phase behavior and fouling

    Energy Technology Data Exchange (ETDEWEB)

    Muhammad, M. [Schlumberger Canada Ltd., Calgary, AB (Canada); Wiehe, I. [Soluble Solutions, Gladstone, NJ (United States)] (comps.)

    2008-07-01

    This conference provided a forum to discuss petroleum phase behaviour and present the latest understanding of the molecular structures and physical interactions of the larger molecules in petroleum. Participants came from universities, petroleum companies, service companies and government laboratories. Topics of discussion included the chemistry, thermodynamics and deposition related to heavy oil, bitumen, asphaltenes, wax, naphthenates and naphthenic acids, as well as petroleum-water emulsions and fouling mechanisms and mitigation. Solids, such as wax and asphaltenes have a tendency to precipitate with changes in temperature and pressure or upon mixing with other petroleum streams. These solid phases can impede or block flow during petroleum production, transport and refining operations. This presentations provided a better understanding of solids deposition to better predict when these problems may occur, so that mitigation methods might be devised. The 5 sessions of the conference were entitled: thermodynamics and rheology of petroleum fluids; asphaltenes; emulsions; flow assurance; and upgrading and refining. All 100 presentations at this conference have been catalogued separately for inclusion in this database. refs.

  15. Encapsulation of titanium dioxide nanoparticles in PLA microspheres using supercritical emulsion extraction to produce bactericidal nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Campardelli, R., E-mail: rcampardelli@unisa.it; Della Porta, G. [University of Salerno, Department of Industrial Engineering (Italy); Gomez, V.; Irusta, S. [University of Zaragoza, Aragon Institute of Nanoscience (INA) (Spain); Reverchon, E., E-mail: ereverchon@unisa.it [University of Salerno, Department of Industrial Engineering (Italy); Santamaria, J., E-mail: jesus.santamaria@unizar.es [University of Zaragoza, Aragon Institute of Nanoscience (INA) (Spain)

    2013-10-15

    In this work, PLA microparticles containing TiO{sub 2} (anatase) nanoparticles have been produced using the Continuous Supercritical Emulsion Extraction technique (SEE-C). A stabilized anatase colloidal suspension (15 {+-} 5 nm) in ethanol aqueous solution was obtained by precipitation from solutions of titanium alkoxides and directly used as the water internal phase of a water-in-oil in water double emulsion or suspended as a powder in the organic phase of a solid-in-oil in water emulsion. Micro- (0.9 {+-} 0.5 {mu}m) and submicro-particles (203 {+-} 40 nm) have been produced, with TiO{sub 2} nominal loadings of 1.2, 2.4, and 3.6 wt%. High TiO{sub 2} encapsulation efficiencies up to about 90 % have been obtained. PLA/TiO{sub 2} particles have been characterized by TEM and XPS to investigate the dispersion of the metal oxide in the polymeric matrix. The photo-assisted bactericidal activity of TiO{sub 2}-containing microparticles against a biofilm-forming strain of Staphylococcus aureus was investigated in specific assays under UV light. Pure TiO{sub 2} nanoparticles and PLA/TiO{sub 2} particles showed the same bactericidal activity.

  16. Encapsulation of titanium dioxide nanoparticles in PLA microspheres using supercritical emulsion extraction to produce bactericidal nanocomposites

    Science.gov (United States)

    Campardelli, R.; Della Porta, G.; Gomez, V.; Irusta, S.; Reverchon, E.; Santamaria, J.

    2013-10-01

    In this work, PLA microparticles containing TiO2 (anatase) nanoparticles have been produced using the Continuous Supercritical Emulsion Extraction technique (SEE-C). A stabilized anatase colloidal suspension (15 ± 5 nm) in ethanol aqueous solution was obtained by precipitation from solutions of titanium alkoxides and directly used as the water internal phase of a water-in-oil in water double emulsion or suspended as a powder in the organic phase of a solid-in-oil in water emulsion. Micro- (0.9 ± 0.5 μm) and submicro-particles (203 ± 40 nm) have been produced, with TiO2 nominal loadings of 1.2, 2.4, and 3.6 wt%. High TiO2 encapsulation efficiencies up to about 90 % have been obtained. PLA/TiO2 particles have been characterized by TEM and XPS to investigate the dispersion of the metal oxide in the polymeric matrix. The photo-assisted bactericidal activity of TiO2-containing microparticles against a biofilm-forming strain of Staphylococcus aureus was investigated in specific assays under UV light. Pure TiO2 nanoparticles and PLA/TiO2 particles showed the same bactericidal activity.

  17. Effect of microdrops deformation on electrical and rheological properties of magnetic fluid emulsion

    International Nuclear Information System (INIS)

    Zakinyan, Arthur R.; Dikansky, Yuri I.

    2017-01-01

    The magnetic fluid emulsions with low interfacial tension have been studied experimentally. The shape deformation of the dispersed phase microdrops under the action of comparatively weak magnetic field has been observed. The effect of microdrops deformation on the macroscopic properties of the emulsion has been investigated. The anisotropic character of emulsion properties in the presence of external magnetic field has been demonstrated. The emulsion dielectric permeability has been measured as a function of the magnetic field strength, the emulsion concentration, and the angle between electrical and magnetic fields. The influence of the droplets deformation under the magnetic field on the rheological behavior of the emulsion has been observed. The obtained results have been analyzed and discussed. - Highlights: • The dispersed phase drops of emulsion studied can be deformed by magnetic field. • The emulsion becomes anisotropic under the action of external field. • The emulsion electrical properties depends on magnetic field strength and direction. • The emulsion rheological behavior can be controlled by external magnetic field.

  18. Transport and Retention of Emulsion Droplets in Sandy Porous Media

    Science.gov (United States)

    Esahani, S. G.; Muller, K.; Chapra, S. C.; Ramsburg, A.

    2014-12-01

    Emulsions are commonly used as amendments during remediation; yet, the processes controlling the distribution of droplets within the subsurface are not well understood. Given that inadequate spatial and/or temporal delivery of amendments often leads to ineffective treatment, there is a need to better understand emulsion transport. Experiments were conducted to evaluate the transport and retention of emulsion droplets in columns containing Ottawa sands. Breakthrough curves and deposition profiles from these experiments were interrogated using a mathematical model capable of describing attachment, detachment, and straining to begin to elucidate the physical processes controlling delivery. Emulsions were constructed by stabilizing soybean oil droplets within a continuous aqueous phase. Physical properties of the resulting oil-in-water emulsions were favorable for subsurface delivery (nominal properties: 1 g/mL density; 10 cP viscosity; and 1.5 μm droplet d50). Emulsions were introduced to the columns for approximately two pore volumes and followed by an extended flush of background solution. Effluent droplet size distributions did not vary significantly over the course of the experiment and remained similar to those measured for the influent emulsion. Emulsion breakthrough curves exhibited tailing, and deposition profiles were found to be hyper-exponential and unaffected by extended periods of background flow. Depending on emulsion composition and flow characteristics, 10-30% of the injected emulsion was retained on the sand suggesting a non-negligible influence on accessible porosity over the course of the experiment. Experimental results were further interpreted using a droplet transport model that accounts for temporal and spatial variation in porosity due to the retention of the emulsion droplets. At present the model assumes a uniform size distribution of inelastic emulsion droplets which are transported by advection and dispersion, and exchanged with the solid

  19. Physicochemical analysis in the evaluation of reconstituted dry emulsion tablets.

    Science.gov (United States)

    Niczinger, Noémi Anna; Kállai-Szabó, Barnabás; Lengyel, Miléna; Gordon, Péter; Klebovich, Imre; Antal, István

    2017-02-05

    The aim of this study was to characterize the formation of emulsions by droplet size analysis and turbidimetry during reconstitution from a solid dosage form, namely from dry emulsion systems, which carry an oil phase for poorly soluble active ingredients. For the dry emulsion systems tablets were prepared either from oil-in-water systems using a freeze-drying process or through direct compression containing the same oil and excipients. The ratios of oil to emulgents and oil to xanthan gum were equal in both methods. In the preparation methods applied, mannitol, erythritol and lactose were used as excipients and mannitol was found to be the most effective excipient based on droplet size reconstitution, turbidimetry and physical properties. Quality control involved testing the physical properties of tablets and characterizing the reconstituted emulsions. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Emulsions, Foams, and Suspensions: The Microscience of the Beverage Industry

    Directory of Open Access Journals (Sweden)

    Alice Vilela

    2018-03-01

    Full Text Available Emulsions and foams form the basis of an extensive variety of materials used in the beverage industry. One of the characteristics of beverage emulsions is that they are rather diluted, contain little amounts of a dispersed oil phase in the finished product, and must remain physically stable for long periods of time. Nowadays, the consumers ask for more than a drink. Thus, in the market, we can find a vast variety of beverages, where emulsion science seems to be the main factor for controlling flavor, color, the presence of constituents of technological or nutritional value, nutraceutical/bioactive components and, also, turbidity. This work intends to make an overview of the recent advances in beverage-emulsions technology. Some examples are given within the very large world of the beverage industry, from cream liqueurs, soft drinks, and functional beverages, to bottled water, fruit drinks, sparkling wine, and beer.

  1. Sardine Fish Oil By Sentrifugation and Adsorbent for Emulsion

    Directory of Open Access Journals (Sweden)

    Kristina Haryati

    2017-04-01

    Full Text Available Sardine fish meal by-product contain eicosapentaenoic acid (EPA and docosahexaenoic (DHA and it can be made as emulsion. The purpose of this study were to determine the best fish oil emulsion by mixingthe oil phase (lecithin 3% and oil and water phase (carboxymethyl cellulose/CMC 2% and fruit juice and then stored until creaming, and the emulsion is analyzed their viscosity, pH, percent of stability and longseparation. Sardine oil is separated from the emulsion and tested oxidation parameters. The best emulsion was fish oil emulsion after refined without citric acid (RTS with viscosity (2470.31 cP, pH (5.64, percent of stability (56.14% and long separation (14 days. Primary and secondary oxidation parameters of RTS  were FFA (14.87%, PV (14.43 meq/kg, AV (32.57 meq KOH/g, AnV (17.3 meq/kg, and Totox (46.16 meq/kg.

  2. Charm studies in emulsion

    CERN Document Server

    Kalinin, Sergey

    Neutrino-nucleon scattering is an effective way to investigate the inner structure of the nucleon, to extract the Standard Model parameters and to explore heavy quarks production dynamics. In the last decades, several experiments have been constructed to study weak interactions of neutrinos with nucleons. One of them was CERN-WA95 experiment operated by the CHORUS collaboration. It is based on a hybrid detector with nuclear emulsion as a target followed by electronic devices. Nuclear emulsion provides three dimensional spatial information with an outstanding resolution of the order of one micron. Therefore, it is ideal to detect short-lived particles. A special technique has been developed to reconstruct events in the emulsion which allows to perform a detailed investigation of events such as charmed hadrons production by neutrinos. As a result, the backround in the selected charm sample is up to six times lower compared to similar experiments. Such a method also permits to make direct measurements of some qu...

  3. Rheology of unstable mineral emulsions

    Directory of Open Access Journals (Sweden)

    Sokolović Dunja S.

    2013-01-01

    Full Text Available In this paper, the rheology of mineral oils and their unstable water emulsion were investigated. The oil samples were domestic crude oil UA, its fractions UA1, UA4 and blend semi-product UP1, while the concentration of oil in water emulsions was in the range from 1 up to 30%. The results were analyzed based on shear stress. The oil samples UA, UA1 and UP1 are Newtonian fluids, while UA4 is pseudoplastic fluid. The samples UA and UA4 show higher value of shear stress (83.75 Pa, 297 Pa, then other two samples UA1 and UP1 (18.41 Pa, 17.52 Pa. Rheology of investigated oils due to its complex chemical composition should be analyzed as a simultaneous effect of all their components. Therefore, structural composition of the oils was determined, namely content of paraffins, naphthenes, aromatics and asphaltenes. All samples contain paraffins, naphthenes and aromatics but only oils UA and UA4 contain asphaltenes as well. All investigated emulsions except 30% EUA4 are Newtonian fluids. The EUA4 30% emulsion shows pseudoplastic behaviour, and it is the only 30% emulsion among investigated ones that achieves lower shear stress then its oil. The characteristics of oil samples that could have an influence on their properties and their emulsion rheology, were determined. These characteristics are: neutralization number, interfacial tension, dielectric constant, and emulsivity. Oil samples UA and UA4 have significantly higher values of neutralization number, dielectric constants, and emulsivity. The sample UA has the lowest value of interface tension and the greatest emulsivity, indicating that this oil, among all investigated, has the highest preference for building emulsion. This could be the reason why 20% and 30% emulsions of the oil UA achieve the highest shear stress among all investigated emulsions.

  4. Development of soy lecithin based novel self-assembled emulsion hydrogels.

    Science.gov (United States)

    Singh, Vinay K; Pandey, Preeti M; Agarwal, Tarun; Kumar, Dilip; Banerjee, Indranil; Anis, Arfat; Pal, Kunal

    2015-03-01

    The current study reports the development and characterization of soy lecithin based novel self-assembled emulsion hydrogels. Sesame oil was used as the representative oil phase. Emulsion gels were formed when the concentration of soy lecithin was >40% w/w. Metronidazole was used as the model drug for the drug release and the antimicrobial tests. Microscopic study showed the apolar dispersed phase in an aqueous continuum phase, suggesting the formation of emulsion hydrogels. FTIR study indicated the formation of intermolecular hydrogen bonding, whereas, the XRD study indicated predominantly amorphous nature of the emulsion gels. Composition dependent mechanical and drug release properties of the emulsion gels were observed. In-depth analyses of the mechanical studies were done using Ostwald-de Waele power-law, Kohlrausch and Weichert models, whereas, the drug release profiles were modeled using Korsmeyer-Peppas and Peppas-Sahlin models. The mechanical analyses indicated viscoelastic nature of the emulsion gels. The release of the drug from the emulsion gels was diffusion mediated. The drug loaded emulsion gels showed good antimicrobial activity. The biocompatibility test using HaCaT cells (human keratinocytes) suggested biocompatibility of the emulsion gels. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. PLGA nanoparticles from nano-emulsion templating as imaging agents: Versatile technology to obtain nanoparticles loaded with fluorescent dyes.

    Science.gov (United States)

    Fornaguera, C; Feiner-Gracia, N; Calderó, G; García-Celma, M J; Solans, C

    2016-11-01

    The interest in polymeric nanoparticles as imaging systems for biomedical applications has increased notably in the last decades. In this work, PLGA nanoparticles, prepared from nano-emulsion templating, have been used to prepare novel fluorescent imaging agents. Two model fluorescent dyes were chosen and dissolved in the oil phase of the nano-emulsions together with PLGA. Nano-emulsions were prepared by the phase inversion composition (PIC) low-energy method. Fluorescent dye-loaded nanoparticles were obtained by solvent evaporation of nano-emulsion templates. PLGA nanoparticles loaded with the fluorescent dyes showed hydrodynamic radii lower than 40nm; markedly lower than those reported in previous studies. The small nanoparticle size was attributed to the nano-emulsification strategy used. PLGA nanoparticles showed negative surface charge and enough stability to be used for biomedical imaging purposes. Encapsulation efficiencies were higher than 99%, which was also attributed to the nano-emulsification approach as well as to the low solubility of the dyes in the aqueous component. Release kinetics of both fluorescent dyes from the nanoparticle dispersions was pH-independent and sustained. These results indicate that the dyes could remain encapsulated enough time to reach any organ and that the decrease of the pH produced during cell internalization by the endocytic route would not affect their release. Therefore, it can be assumed that these nanoparticles are appropriate as systemic imaging agents. In addition, in vitro toxicity tests showed that nanoparticles are non-cytotoxic. Consequently, it can be concluded that the preparation of PLGA nanoparticles from nano-emulsion templating represents a very versatile technology that enables obtaining biocompatible, biodegradable and safe imaging agents suitable for biomedical purposes. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Internal friction and linear expansion coefficient in zirconium and cobalt within the range of phase transitions

    International Nuclear Information System (INIS)

    Boyarskij, S.V.

    1986-01-01

    Experimental results are presented for internal friction and linear expansion coefficient at zirconium and cobalt in the temperature range from 440 K to the point of the phase transition of the first kind (1138 K for Zr and 706 for Co). Anomalous changes of the internal friction and linear expansion coefficient in the phase transition region are found. Theoretical considerations are given to explain the sharp decrease of the internal friction as temperature approaches the phase transition point

  7. The role of Saccharomyces cerevisiae in stabilizing emulsions of hexadecane in aqueous media.

    Science.gov (United States)

    Meirelles, Aureliano Agostinho Dias; da Cunha, Rosiane Lopes; Gombert, Andreas Karoly

    2018-04-01

    During downstream operations involved in the purification of hydrophobic biofuels produced by microorganisms, undesired stable emulsions may be formed. Understanding the mechanisms behind this stability is a pre-requisite for designing cost-effective strategies to break these emulsions. In this work, we aimed at increasing our knowledge on the mechanisms responsible for stabilizing yeast-containing oil-in-water emulsions. For this purpose, emulsions containing hexadecane and different yeast-based aqueous phases were prepared and analyzed for phase separation, surface charge density, particle size, and rheology. First, we observed that compounds present in fresh tablet baker's yeast contribute to emulsion stability. In order to eliminate this effect, we generated stocks with this yeast in the laboratory, and compared its performance with an industrial fuel ethanol strain, namely Saccharomyces cerevisiae PE-2. We confirmed that the presence of yeast cells enhances emulsion stability. The cultivation medium (complex or defined) in which cells are grown, as well as the physiological state of the cells (pre- or post-diauxic), prior to emulsion preparation, influenced emulsion stability. The smaller cell size of tablet yeast probably also contributes to more stable emulsions, when compared to those prepared with yeast cells grown in the laboratory. Baker's and fuel ethanol yeast cells in post-diauxic phase promote the formation of more stable emulsions than those with cells in the pre-diauxic physiological state. Finally, we propose a mechanism to explain the enhanced emulsion stability due to the presence of yeast cells, with electrostatic repulsion between emulsion droplets having the prevailing effect.

  8. Fabrication and Properties of Micro-Nanoencapsulated Phase Change Materials for Internally-Cooled Liquid Desiccant Dehumidification

    Directory of Open Access Journals (Sweden)

    Xiaofeng Niu

    2017-04-01

    Full Text Available Micro-nanoencapsulated phase change materials (M-NEPCMs are proposed to be useful in liquid desiccant dehumidification by restraining the temperature rise in the moisture-removal process and improving the dehumidification efficiency. In this paper, the n-octadecane M-NEPCMs with desirable thermal properties for internally-cooled dehumidification were fabricated by using compound emulsifiers through the in-situ polymerization method. Melamine-formaldehyde resin was used as the shell material. The effects of the mixing ratio, emulsification methods and amount of the compound emulsifiers on the morphology, size and thermal properties of the M-NEPCMs were investigated experimentally. The optimum weight mixing ratio of the compound emulsifiers is SDS (sodium dodecyl sulfate:Tween80 (polyoxyethylene sorbitan monooleate:Span80 (sorbitan monooleate = 0.1:0.6:0.3, which achieves the best stability of the n-octadecane emulsion. When the compound emulsifiers are 10 wt. % of the core material, the melting enthalpy of M-NEPCMs reaches its maximum of 145.26 J/g of capsules, with an encapsulation efficiency of 62.88% and a mean diameter of 636 nm. The sub-cooling of the prepared M-NEPCMs is lower than 3 °C, with an acceptable thermal reliability after the thermal cycling test. A pre-emulsification prior to the addition of deionized water in the emulsification is beneficial to the morphology of the capsules, as the phase change enthalpy can be increased by 123.7%.

  9. Pickering emulsions prepared by layered niobate K₄Nb₆O₁₇ intercalated with organic cations and photocatalytic dye decomposition in the emulsions.

    Science.gov (United States)

    Nakato, Teruyuki; Ueda, Hiroaki; Hashimoto, Sachika; Terao, Ryosuke; Kameyama, Miyuki; Mouri, Emiko

    2012-08-01

    We investigated emulsions stabilized with particles of layered hexaniobate, known as a semiconductor photocatalyst, and photocatalytic degradation of dyes in the emulsions. Hydrophobicity of the niobate particles was adjusted with the intercalation of alkylammonium ions into the interlayer spaces to enable emulsification in a toluene-water system. After the modification of interlayer space with hexylammonium ions, the niobate stabilized water-in-oil (w/o) emulsions in a broad composition range. Optical microscopy showed that the niobate particles covered the surfaces of emulsion droplets and played a role of emulsifying agents. The niobate particles also enabled the generation of oil-in-water (o/w) emulsions in a limited composition range. Modification with dodecylammonium ions, which turned the niobate particles more hydrophobic, only gave w/o emulsions, and the particles were located not only at the toluene-water interface but also inside the toluene continuous phase. On the other hand, interlayer modification with butylammonium ions led to the formation of o/w emulsions. When porphyrin dyes were added to the system, the cationic dye was adsorbed on niobate particles at the emulsion droplets whereas the lipophilic dye was dissolved in toluene. Upon UV irradiation, both of the dyes were degraded photocatalytically. When the cationic and lipophilic porphyrin molecules were simultaneously added to the emulsions, both of the dyes were photodecomposed nonselectively.

  10. Storage stability of marine phospholipids emulsions

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline Pascale

    Marine phospholipids (MPL) are believed to provide more advantages than fish oil from the same source. They are considered to have a better bioavailability, a better resistance towards oxidation and a higher content of polyunsaturated fatty acids such as eicosapentaenoic (EPA) and docosahexaenoic...... of secondary volatile compounds by Solid Phase Microextraction at several time intervals at 2°C storage. Preliminary results showed that marine phospholipids emulsion has a good oxidative stability........ In addition, preliminary investigation of the oxidative and hydrolytic stability was carried out through determination of Peroxide Value and Free Fatty Acids Value after 32 days storage at room temperature and 2ºC, respectively. Oxidative stability of MPL emulsions were also investigated through measurement...

  11. Experiments and network model of flow of oil-water emulsion in porous media.

    Science.gov (United States)

    Romero, Mao Illich; Carvalho, Marcio S; Alvarado, Vladimir

    2011-10-01

    Transport of emulsions in porous media is relevant to several subsurface applications. Many enhanced oil recovery (EOR) processes lead to emulsion formation and as a result conformance originating in the flow of a dispersed phase may arise. In some EOR processes, emulsion is injected directly as a mobility control agent. Modeling the flow of emulsion in porous media is extremely challenging due to the complex nature of the associated flows and numerous interfaces. The descriptions based on effective viscosity are not valid when the drop size is of the same order of magnitude as the pore-throat characteristic length scale. An accurate model of emulsion flow through porous media should describe this local change in mobility. The available filtration models do not take into account the variation of the straining and capturing rates with the local capillary number. In this work, we present experiments of emulsion flow through sandstone cores of different permeability and a first step on a capillary network model that uses experimentally determined pore-level constitutive relationships between flow rate and pressure drop in constricted capillaries to obtain representative macroscopic flow behavior emerging from microscopic emulsion flow at the pore level. A parametric analysis is conducted to study the effect of the permeability and dispersed phase droplet size on the flow response to emulsion flooding in porous media. The network model predictions qualitatively describe the oil-water emulsion flow behavior observed in the experiments.

  12. Physical stability of R-(+)-Limonene emulsions stabilized by Ulva fasciata algae polysaccharide.

    Science.gov (United States)

    Shao, Ping; Ma, Huiling; Qiu, Qiang; Jing, Weiping

    2016-11-01

    The physical stability of R-(+)-Limonene emulsions stabilized by Ulva fasciata polysaccharide (UFP) was investigated in this study. Emulsion physical stability was evaluated under different polysaccharide concentrations (1%-5%, wt/wt) and pH values (3.0-11.0). The stability of R-(+)-Limonene emulsions was demonstrated by droplet size distribution, rheological properties, zeta potential and visual phase separation. R-(+)-Limonene emulsions displayed monomodal droplet size distributions, high absolute values of zeta potential and good storage stability when 3% (wt/wt) UFP was used. The rheological properties and stability of R-(+)-Limonene emulsions appeared to be dependent on polysaccharide concentration. The emulsion stability was impacted by pH. Higher zeta potential (-52.6mV) and smaller mean droplet diameter (2.45μm) were achieved in neutral liquid environment (pH 7.0). Extreme acidity caused the flocculation of emulsions, which was manifested as phase separation, while emulsions were quite stable in an alkaline environment. Through comparing the stabilities of emulsions stabilized by different emulsifiers (i.e. UFP, GA and Gelatin), the result suggested that UFP was the best emulsifying agent among them. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Phytosterol colloidal particles as Pickering stabilizers for emulsions.

    Science.gov (United States)

    Liu, Fu; Tang, Chuan-He

    2014-06-04

    Water-insoluble phytosterols were developed into a kind of colloidal particle as Pickering stabilizers for emulsions by a classic anti-solvent method using 100% ethanol as the organic phase to solubilize the phytosterols and whey protein concentrate (WPC) as the emulsifier. The colloidal particles in the dispersion, with morphology of stacked platelet-like sheets, had a mean diameter of 44.7 and 24.7 μm for the volume- and surface-averaged sizes, respectively. The properties and stability of the emulsions stabilized by these colloidal particles were highly dependent upon the applied total solid concentration (c; in the dispersion) and oil fraction (ø). The results indicated that (1) at a low c value (emulsions were susceptible to phase separation, even at a low ø of 0.2, (2) at low ø values (e.g., 0.2 or 0.3) and a relatively high c value (1.0%, w/v, or above), a severe droplet flocculation occurred for the emulsions, and (3) when both c and ø were appropriately high, a kind of self-supporting gel-like emulsions could be formed. More interestingly, a phase inversion of the emulsions from the oil-in-water to water-in-oil type was observed, upon the ø increasing from 0.2 to 0.6 (especially at high c values, e.g., 3.0%, w/v). The elaborated Pickering emulsions stabilized by the phytosterol colloidal particles with a gel-like behavior would provide a candidate to act as a novel delivery system for active ingredients.

  14. Microfluidic channel structures speed up mixing of multiple emulsions by a factor of ten

    CSIR Research Space (South Africa)

    Land, KJ

    2014-09-01

    Full Text Available We present a novel use for channel structures in microfluidic devices, whereby two two-phase emulsions, one created on-chip, the other off-chip, are rapidly mixed with each other in order to allow for the coalescence of one emulsion with the other...

  15. Complex formation in mixtures of lysozyme-stabilized emulsions and human saliva

    NARCIS (Netherlands)

    Silletti, E.; Vingerhoeds, M.H.; Norde, W.; Aken, van G.A.

    2007-01-01

    In this paper, we studied the interaction between human unstimulated saliva and lysozyme-stabilized oil-in-water emulsions (10 wt/wt% oil phase, 10 mM NaCl, pH 6.7), to reveal the driving force for flocculation of these emulsions. Confocal scanning laser microscopy (CSLM) showed formation of

  16. A quality by design approach to optimization of emulsions for electrospinning using factorial and D-optimal designs.

    Science.gov (United States)

    Badawi, Mariam A; El-Khordagui, Labiba K

    2014-07-16

    Emulsion electrospinning is a multifactorial process used to generate nanofibers loaded with hydrophilic drugs or macromolecules for diverse biomedical applications. Emulsion electrospinnability is greatly impacted by the emulsion pharmaceutical attributes. The aim of this study was to apply a quality by design (QbD) approach based on design of experiments as a risk-based proactive approach to achieve predictable critical quality attributes (CQAs) in w/o emulsions for electrospinning. Polycaprolactone (PCL)-thickened w/o emulsions containing doxycycline HCl were formulated using a Span 60/sodium lauryl sulfate (SLS) emulsifier blend. The identified emulsion CQAs (stability, viscosity and conductivity) were linked with electrospinnability using a 3(3) factorial design to optimize emulsion composition for phase stability and a D-optimal design to optimize stable emulsions for viscosity and conductivity after shifting the design space. The three independent variables, emulsifier blend composition, organic:aqueous phase ratio and polymer concentration, had a significant effect (pemulsion CQAs, the emulsifier blend composition exerting prominent main and interaction effects. Scanning electron microscopy (SEM) of emulsion-electrospun NFs and desirability functions allowed modeling of emulsion CQAs to predict electrospinnable formulations. A QbD approach successfully built quality in electrospinnable emulsions, allowing development of hydrophilic drug-loaded nanofibers with desired morphological characteristics. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Generation of colloidal granules and capsules from double emulsion drops

    Science.gov (United States)

    Hess, Kathryn S.

    Assemblies of colloidal particles are extensively used in ceramic processing, pharmaceuticals, inks and coatings. In this project, the aim was to develop a new technique to fabricate monodispersed colloidal assemblies. The use of microfluidic devices and emulsion processing allows for the fabrication of complex materials that can be used in a variety of applications. A microfluidic device is used to create monodispersed water/oil/water (w/o/w) double emulsions with interior droplets of colloidal silica suspension ranging in size from tens to hundreds of microns. By tailoring the osmotic pressure using glycerol as a solute in the continuous and inner phases of the emulsion, we can control the final volume size of the monodispersed silica colloidal crystals that form in the inner droplets of the double emulsion. Modifying the ionic strength in the colloidal dispersion can be used to affect the particle-particle interactions and crystal formation of the final colloidal particle. This w/o/w technique has been used with other systems of metal oxide colloids and cellulose nanocrystals. Encapsulation of the colloidal suspension in a polymer shell for the generation of ceramic-polymer core-shell particles has also been developed. These core-shell particles have spawned new research in the field of locally resonant acoustic metamaterials. Systems and chemistries for creating cellulose hydrogels within the double emulsions have also been researched. Water in oil single emulsions and double emulsions have been used to create cellulose hydrogel spheres in the sub-100 micron diameter range. Oil/water/oil double emulsions allow us to create stable cellulose capsules. The addition of a second hydrogel polymer, such as acrylate or alginate, further strengthens the cellulose gel network and can also be processed into capsules and particles using the microfluidic device. This work could have promising applications in acoustic metamaterials, personal care products, pharmaceuticals

  18. NASA Physical Sciences - Presentation to Annual Two Phase Heat Transfer International Topical Team Meeting

    Science.gov (United States)

    Chiaramonte, Francis; Motil, Brian; McQuillen, John

    2014-01-01

    The Two-phase Heat Transfer International Topical Team consists of researchers and members from various space agencies including ESA, JAXA, CSA, and RSA. This presentation included descriptions various fluid experiments either being conducted by or planned by NASA for the International Space Station in the areas of two-phase flow, flow boiling, capillary flow, and crygenic fluid storage.

  19. Aligned Porous Beads Prepared by Frozen Polymerization of Emulsion-Templates Involving Tiny Emulsifier

    Directory of Open Access Journals (Sweden)

    Lu Zhen

    2016-01-01

    Full Text Available High internal phase emulsion (HIPE templated porous materials are attracting increasing interests due to its high porosity and tunable structure. However, large amounts (5-50 vol% of suitable non-ionic surfactants are commonly required to stabilize conventional HIPE due to the high internal volume fraction of HIPE. In this work, applying frozen polymerization in HIPE, aligned porous beads were prepared with tiny surfactant (~0.1 wt%. These interconnected aligned porous beads were prepared through directional freezing, and frozen ultraviolet (UV initiation of an oil-in-water (o/w HIPE. The HIPEs are extruded by needle, and then directionally frozen in liquid nitrogen to form beads. The frozen beads were exposed under UV irradiation in a -20 °C ethanol bath to initiate the monomers in the aqueous phase. Moreover, the morphology of the resulting porous beads were tailored by vary the ratio of oil/water and the amount of emulsifier.

  20. Dynamically reconfigurable complex emulsions via tunable interfacial tensions

    Science.gov (United States)

    Zarzar, Lauren D.; Sresht, Vishnu; Sletten, Ellen M.; Kalow, Julia A.; Blankschtein, Daniel; Swager, Timothy M.

    2015-02-01

    Emulsification is a powerful, well-known technique for mixing and dispersing immiscible components within a continuous liquid phase. Consequently, emulsions are central components of medicine, food and performance materials. Complex emulsions, including Janus droplets (that is, droplets with faces of differing chemistries) and multiple emulsions, are of increasing importance in pharmaceuticals and medical diagnostics, in the fabrication of microparticles and capsules for food, in chemical separations, in cosmetics, and in dynamic optics. Because complex emulsion properties and functions are related to the droplet geometry and composition, the development of rapid, simple fabrication approaches allowing precise control over the droplets' physical and chemical characteristics is critical. Significant advances in the fabrication of complex emulsions have been made using a number of procedures, ranging from large-scale, less precise techniques that give compositional heterogeneity using high-shear mixers and membranes, to small-volume but more precise microfluidic methods. However, such approaches have yet to create droplet morphologies that can be controllably altered after emulsification. Reconfigurable complex liquids potentially have great utility as dynamically tunable materials. Here we describe an approach to the one-step fabrication of three- and four-phase complex emulsions with highly controllable and reconfigurable morphologies. The fabrication makes use of the temperature-sensitive miscibility of hydrocarbon, silicone and fluorocarbon liquids, and is applied to both the microfluidic and the scalable batch production of complex droplets. We demonstrate that droplet geometries can be alternated between encapsulated and Janus configurations by varying the interfacial tensions using hydrocarbon and fluorinated surfactants including stimuli-responsive and cleavable surfactants. This yields a generalizable strategy for the fabrication of multiphase emulsions with

  1. Controlled Generation of Ultrathin-Shell Double Emulsions and Studies on Their Stability.

    Science.gov (United States)

    Zhao, Chun-Xia; Chen, Dong; Hui, Yue; Weitz, David A; Middelberg, Anton P J

    2017-05-19

    Double emulsions with a hierarchical core-shell structure have great potential in various applications, but their broad use is limited by their instability. To improve stability, water-in-oil-in-water (W/O/W) emulsions with an ultrathin oil layer of several hundred nanometres were produced by using a microcapillary device. The effects of various parameters on the generation of ultrathin-shell double emulsions and their droplet size were investigated, including the proper combinations of inner, middle and outer phases, flow rates and surfactants. The surfactant in the middle oil phase was found to be critical for the formation of the ultrathin-shell double emulsions. Furthermore, the stability of these double emulsions can be notably improved by increasing the concentration of the surfactant, and they can be stable for months. This opens up new opportunities for their future applications in cosmetics, foods and pharmaceuticals. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. In vitro skin permeation of sunscreen agents from O/W emulsions.

    Science.gov (United States)

    Montenegro, L; Carbone, C; Paolino, D; Drago, R; Stancampiano, A H; Puglisi, G

    2008-02-01

    The effects of different emulsifiers on the in vitro permeation through human skin of two sunscreen agents [octylmethoxycinnamate (OMC) and butylmethoxydibenzoylmethane (BMBM)] were investigated from O/W emulsions. The test formulations were prepared using the same oil and aqueous phase ingredients and the following emulsifier and coemulsifier systems: Emulgade SE((R)) (ceteareth-12 and ceteareth-20 and cetearyl alcohol and cetyl palmitate) and glycerylmonostearate (emulsion 1); Brij 72((R)) (steareth-2), Brij 721((R)) (steareth-21) and cetearyl alcohol (emulsion 2); Phytocream((R)) (potassium palmitoyl-hydrolysed wheat protein and glyceryl stearate and cetearyl alcohol) and glycerylmonostearate (emulsion 3); Montanov 68((R)) (cetearyl glucoside and cetearyl alcohol) (emulsion 4); Xalifin-15((R)) (C(15-20) acid PEG-8 ester) and cetearyl alcohol (emulsion 5). The cumulative amount of OMC that permeated in vitro through human skin after 22 h from the formulations being tested decreased in the order 3 > 1 congruent with 4 > 5 > 2 and was about nine-fold higher from emulsion 3 compared with that from emulsion 2. As regards BMBM, no significant difference was observed as regards its skin permeation from emulsions 1, 3, 4 and 5, whereas formulation 2 allowed significantly lower amounts of BMBM to permeate the skin. In vitro release experiments of OMC and BMBM from emulsions 1-6 through cellulose acetate membranes showed that only emulsions 4 and 5 provided pseudo-first-order release rates only for OMC. The results of this study suggest that the type of emulsifying systems used to prepare an O/W emulsion may strongly affect sunscreen skin permeation from these formulations. Therefore, the vehicle effects should be carefully considered in the formulation of sunscreen products.

  3. International workshop on phase retrieval and coherent scattering. Coherence 2005

    International Nuclear Information System (INIS)

    Nugent, K.A.; Fienup, J.R.; Van Dyck, D.; Van Aert, S.; Weitkamp, T.; Diaz, A.; Pfeiffer, F.; Cloetens, P.; Stampanoni, M.; Bunk, O.; David, C.; Bronnikov, A.V.; Shen, Q.; Xiao, X.; Gureyev, T.E.; Nesterets, Ya.I.; Paganin, D.M.; Wilkins, S.W.; Mokso, R.; Cloetens, P.; Ludwig, W.; Hignette, O.; Maire, E.; Faulkner, H.M.L.; Rodenburg, J.M.; Wu, X.; Liu, H.; Grubel, G.; Ludwig, K.F.; Livet, F.; Bley, F.; Simon, J.P.; Caudron, R.; Le Bolloc'h, D.; Moussaid, A.; Gutt, C.; Sprung, M.; Madsen, A.; Tolan, M.; Sinha, S.K.; Scheffold, F.; Schurtenberger, P.; Robert, A.; Madsen, A.; Falus, P.; Borthwick, M.A.; Mochrie, S.G.J.; Livet, F.; Sutton, M.D.; Ehrburger-Dolle, F.; Bley, F.; Geissler, E.; Sikharulidze, I.; Jeu, W.H. de; Lurio, L.B.; Hu, X.; Jiao, X.; Jiang, Z.; Lurio, L.B.; Hu, X.; Jiao, X.; Jiang, Z.; Naryanan, S.; Sinha, S.K.; Lal, J.; Naryanan, S.; Sinha, S.K.; Lal, J.; Robinson, I.K.; Chapman, H.N.; Barty, A.; Beetz, T.; Cui, C.; Hajdu, J.; Hau-Riege, S.P.; He, H.; Stadler, L.M.; Sepiol, B.; Harder, R.; Robinson, I.K.; Zontone, F.; Vogl, G.; Howells, M.; London, R.; Marchesini, S.; Shapiro, D.; Spence, J.C.H.; Weierstall, U.; Eisebitt, S.; Shapiro, D.; Lima, E.; Elser, V.; Howells, M.R.; Huang, X.; Jacobsen, C.; Kirz, J.; Miao, H.; Neiman, A.; Sayre, D.; Thibault, P.; Vartanyants, I.A.; Robinson, I.K.; Onken, J.D.; Pfeifer, M.A.; Williams, G.J.; Pfeiffer, F.; Metzger, H.; Zhong, Z.; Bauer, G.; Nishino, Y.; Miao, J.; Kohmura, Y.; Yamamoto, M.; Takahashi, Y.; Koike, K.; Ebisuzaki, T.; Ishikawa, T.; Spence, J.C.H.; Doak, B.

    2005-01-01

    The contributions of the participants have been organized into 3 topics: 1) phase retrieval methods, 2) X-ray photon correlation spectroscopy, and 3) coherent diffraction imaging. This document gathers the abstracts of the presentations and of the posters

  4. CRISSP - Customizable Recyclable International Space Station Packaging, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The CRISSP Phase II effort will mature to TRL-6 recyclable launch packaging materials to enable sustainable in-space manufacturing on the ISS and future manned deep...

  5. International workshop on phase retrieval and coherent scattering. Coherence 2005

    Energy Technology Data Exchange (ETDEWEB)

    Nugent, K.A.; Fienup, J.R.; Van Dyck, D.; Van Aert, S.; Weitkamp, T.; Diaz, A.; Pfeiffer, F.; Cloetens, P.; Stampanoni, M.; Bunk, O.; David, C.; Bronnikov, A.V.; Shen, Q.; Xiao, X.; Gureyev, T.E.; Nesterets, Ya.I.; Paganin, D.M.; Wilkins, S.W.; Mokso, R.; Cloetens, P.; Ludwig, W.; Hignette, O.; Maire, E.; Faulkner, H.M.L.; Rodenburg, J.M.; Wu, X.; Liu, H.; Grubel, G.; Ludwig, K.F.; Livet, F.; Bley, F.; Simon, J.P.; Caudron, R.; Le Bolloc' h, D.; Moussaid, A.; Gutt, C.; Sprung, M.; Madsen, A.; Tolan, M.; Sinha, S.K.; Scheffold, F.; Schurtenberger, P.; Robert, A.; Madsen, A.; Falus, P.; Borthwick, M.A.; Mochrie, S.G.J.; Livet, F.; Sutton, M.D.; Ehrburger-Dolle, F.; Bley, F.; Geissler, E.; Sikharulidze, I.; Jeu, W.H. de; Lurio, L.B.; Hu, X.; Jiao, X.; Jiang, Z.; Lurio, L.B.; Hu, X.; Jiao, X.; Jiang, Z.; Naryanan, S.; Sinha, S.K.; Lal, J.; Naryanan, S.; Sinha, S.K.; Lal, J.; Robinson, I.K.; Chapman, H.N.; Barty, A.; Beetz, T.; Cui, C.; Hajdu, J.; Hau-Riege, S.P.; He, H.; Stadler, L.M.; Sepiol, B.; Harder, R.; Robinson, I.K.; Zontone, F.; Vogl, G.; Howells, M.; London, R.; Marchesini, S.; Shapiro, D.; Spence, J.C.H.; Weierstall, U.; Eisebitt, S.; Shapiro, D.; Lima, E.; Elser, V.; Howells, M.R.; Huang, X.; Jacobsen, C.; Kirz, J.; Miao, H.; Neiman, A.; Sayre, D.; Thibault, P.; Vartanyants, I.A.; Robinson, I.K.; Onken, J.D.; Pfeifer, M.A.; Williams, G.J.; Pfeiffer, F.; Metzger, H.; Zhong, Z.; Bauer, G.; Nishino, Y.; Miao, J.; Kohmura, Y.; Yamamoto, M.; Takahashi, Y.; Koike, K.; Ebisuzaki, T.; Ishikawa, T.; Spence, J.C.H.; Doak, B

    2005-07-01

    The contributions of the participants have been organized into 3 topics: 1) phase retrieval methods, 2) X-ray photon correlation spectroscopy, and 3) coherent diffraction imaging. This document gathers the abstracts of the presentations and of the posters.

  6. A Dewetting Model for Double-Emulsion Droplets

    Directory of Open Access Journals (Sweden)

    Zhanxiao Kang

    2016-11-01

    Full Text Available The evolution of double-emulsion droplets is of great importance for the application of microdroplets and microparticles. We study the driving force of the dewetting process, the equilibrium configuration and the dewetting time of double-emulsion droplets. Through energy analysis, we find that the equilibrium configuration of a partial engulfed droplet depends on a dimensionless interfacial tension determined by the three relevant interfacial tensions, and the engulfing part of the inner phase becomes larger as the volume of the outer phase increases. By introducing a dewetting boundary, the dewetting time can be calculated by balancing the driving force, caused by interfacial tensions, and the viscous force. Without considering the momentum change of the continuous phase, the dewetting time is an increasing function against the viscosity of the outer phase and the volume ratio between the outer phase and inner phase.

  7. Research ICT Africa (RIA!) - phase III | Page 9 | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Research ICT Africa (RIA!) - phase III. Depuis la création du réseau RIA! en 2003, ses responsables ont mené avec succès des études portant tant sur l'offre que sur la demande afin de permettre de mieux comprendre l'accès aux TIC et leur utilisation en Afrique. Au cours des deux premières phases du projet (nos 101584 ...

  8. Research ICT Africa (RIA!) - phase III | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Research ICT Africa (RIA!) - phase III. Depuis la création du réseau RIA! en 2003, ses responsables ont mené avec succès des études portant tant sur l'offre que sur la demande afin de permettre de mieux comprendre l'accès aux TIC et leur utilisation en Afrique. Au cours des deux premières phases du projet (nos 101584 ...

  9. Emulsifier development for high-concentrated reverse emulsions

    Directory of Open Access Journals (Sweden)

    I.L. Kovalenko

    2016-05-01

    Full Text Available The reverse emulsions have found broad application in ore mining industry as matrixes of emulsion explosive substances and boring washing waters. The defining characteristic of reverse emulsions of industrial explosive substances is the high stability and immunity to crystallization. Aim: The aim of this work is to assess the mechanism of emulsifiers effect like SMO and some PIBSA-derivatives, that are most abundantly used in world practice, and also to develop an effective domestic emulsifier of reverse emulsions. Materials and methods: Using the semi-dynamic method with use of the reverse stalagmometer it was determined the decreasing in interfacial tension on “water / diesel fuel” border in the presence of 0.5 wt % sorbitan monooleate of various producers. Emulsions with use of the chosen emulsifiers using the dynamic mixer on the basis of monosolution of ammonium nitrate and diesel fuel have been produced. The emulsions have the following composition, wt %: ammonium nitrate – 76.8; water – 15.6; diesel fuel – 6.0; emulsifier – 1.6. Results: By the researches results of the interfacial tension “surfactant water / solution in diesel fuel”, the stability of emulsions using monosolution of ammonium nitrate and the IR spectrums of SMO of various producers it is established that presence in product of impurity of oleic acid, di- and trioleates leads to decreasing in interphase activity, increasing of emulsifier oil solubility and decreasing the resistance of emulsions to crystallization. On the basis of the spectral data analysis it is suggested about possibility of specific interaction on the mechanism of “spectral resonance” between emulsifiers of the PIBSA-MEA, LZX type and crystals nucleus of NH4NO3 ammonium nitrate in dispersed phase of emulsion. Amidation of vegetable oils by monoethanol amine is implemented at the reduced temperatures (90…100 °C. It was proved the availability mainly of fatty acids amides in product

  10. Elucidation of stabilizing oil-in-water Pickering emulsion with different modified maize starch-based nanoparticles.

    Science.gov (United States)

    Ye, Fan; Miao, Ming; Jiang, Bo; Campanella, Osvaldo H; Jin, Zhengyu; Zhang, Tao

    2017-08-15

    The aim of present study was to study the medium-chain triacylglycerol-in-water (O/W) Pickering emulsion stabilized using different modified starch-based nanoparticles (octenylsuccinylation treated soluble starch nanoparticle, OSA-SSNP, and insoluble starch nanoparticle, ISNP). The major factors for affecting the system stability, rheological behaviour and microstructure of the emulsions were also investigated. The parameters of the O/W emulsions stabilized by OSA-SSNP or ISNP were selected as follows: 3.0% of starch nanoparticles concentration, 50% of MCT fraction and 7.0 of system pH. The rheological properties indicated that both emulsions displayed shear-thinning behaviour as a non-Newtonian fluid. For OSA-SSNP, the viscosities of the emulsion were higher than those of ISNP throughout shear rate range for the same condition. The plot of droplet size distribution for emulsion stabilized OSA-SSNP appeared as a single narrow peak, whereas a broader droplet size distribution with bimodal pattern was observed for emulsion stabilized ISNP. The microscopy results showed that both OSA-SSNP and ISNP were adsorbed at oil-water interface to form a barrier film and retard the phase separation. When emulsion was stored for 30d, no phase separation was detected for O/W emulsion, revealing high stability of emulsion stabilized by both OSA-SSNP and ISNP. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. The CTFA Evaluation of Alternatives Program: an evaluation of in vitro alternatives to the Draize primary eye irritation test. (Phase II) oil/water emulsions.

    Science.gov (United States)

    Gettings, S D; Dipasquale, L C; Bagley, D M; Casterton, P L; Chudkowski, M; Curren, R D; Demetrulias, J L; Feder, P I; Galli, C L; Gay, R

    1994-10-01

    The Cosmetic, Toiletry and Fragrance Association (CTFA) Evaluation of Alternatives Program is an evaluation of the relationship between Draize ocular safety test data and comparable data from a selection of in vitro tests. In Phase II, 18 representative oil/water-based personal-care formulations were subjected to the Draize primary eye safety test and 30 in vitro assay protocols (14 different types of in vitro endpoints were evaluated; the remainder were protocol variations). Correlation of in vitro with in vivo data was evaluated using analysis of sensitivity/specificity and statistical analysis of the relationship between maximum average Draize score (MAS) and in vitro endpoint. Regression modelling is the primary approach adopted in the CTFA Program for evaluating in vitro assay performance. The objective of regression analysis is to predict MAS for a given test material (and to place upper and lower prediction interval bounds on the range in which the MAS is anticipated to fall with high probability) conditional on observing an in vitro assay score for that material. The degree of confidence in prediction is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curves: the narrower the prediction interval, the more predictive of the Draize score is the in vitro test result. 16 assays were shown to have the greatest agreement with the Draize procedure and were therefore selected for regression analysis. Based on the magnitude of the 95% prediction bounds of each of the 16 selected assays over the range of test data, it may be inferred that prediction of MAS values from experimentally determined in vitro scores is more accurate for oil/water-based formulations with lower rather than higher irritancy potential. The assays selected for modelling in Phase II generally exhibited weaker relationships with MAS than those selected in Phase I (evaluated using hydroalcoholic formulations), even though several assays

  12. Amateur Radio on the International Space Station - Phase 2 Hardware System

    Science.gov (United States)

    Bauer, F.; McFadin, L.; Bruninga, B.; Watarikawa, H.

    2003-01-01

    The International Space Station (ISS) ham radio system has been on-orbit for over 3 years. Since its first use in November 2000, the first seven expedition crews and three Soyuz taxi crews have utilized the amateur radio station in the Functional Cargo Block (also referred to as the FGB or Zarya module) to talk to thousands of students in schools, to their families on Earth, and to amateur radio operators around the world. Early on, the Amateur Radio on the International Space Station (ARISS) international team devised a multi-phased hardware development approach for the ISS ham radio station. Three internal development Phases. Initial Phase 1, Mobile Radio Phase 2 and Permanently Mounted Phase 3 plus an externally mounted system, were proposed and agreed to by the ARISS team. The Phase 1 system hardware development which was started in 1996 has since been delivered to ISS. It is currently operational on 2 meters. The 70 cm system is expected to be installed and operated later this year. Since 2001, the ARISS international team have worked to bring the second generation ham system, called Phase 2, to flight qualification status. At this time, major portions of the Phase 2 hardware system have been delivered to ISS and will soon be installed and checked out. This paper intends to provide an overview of the Phase 1 system for background and then describe the capabilities of the Phase 2 radio system. It will also describe the current plans to finalize the Phase 1 and Phase 2 testing in Russia and outlines the plans to bring the Phase 2 hardware system to full operation.

  13. Optimization of Finasteride Nano-Emulsion Preparation Using ...

    African Journals Online (AJOL)

    (finasteride as a lipophilic drug) and water–miscible solvent with or without lipophilic surfactant (Span®. 80), while the aqueous phase consisted of water with or without hydrophilic surfactant (Tween® 80). Chemometric approach was applied for optimizing the size of the nano-emulsion droplets. For this purpose, the effect ...

  14. Emulsion stability: determination from turbidity

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, S.R.; Fogler, H.S.

    1981-01-01

    The relationship between particle size and concentration and turbidity has been developed for a polydispersed system. The stability of acoustically prepared emulsions of C36H74 in water were determined from turbidimetry and found to be in agreement with the stability determined by the freezing method. The turbidimetry method can be used for determining the stability of various emulsions easily and inexpensively. 11 references.

  15. Research ICT Africa - Phase III | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    During this phase, RIA will construct an African index of ICT policy and regulations; establish a network structure suitable for growth and the integration of North Africa; refine its policy influence and dissemination strategy; integrate its supply- and demand-side data and triangulate it with the telecommunication regulatory ...

  16. Automatic scanning of emulsion films

    International Nuclear Information System (INIS)

    D'Ambrosio, N.; Mandrioli, G.; Sirrib, G.

    2003-01-01

    The use of nuclear emulsions in recent large neutrino experiments is mostly due to the significant results in the developments of this detection technique. In the emulsion films, trajectories of through-going particles are permanently recorded: thus, the emulsion target can be considered not only as a tracking but also as a storing device. If the data readout is performed by automatic scanning systems interfaced to an acquisition computer equipped with a fast frame grabber, nuclear emulsions can be used as very large target detector and quickly analyzed in particle physics experiments. Techniques for automatic scanning of nuclear emulsions have been developed in the early past. The effort was initiated by Niwa at Nagoya (Japan) in the late 70s. The first large-scale application was the CHORUS experiment; then emulsions have been used to search for T neutrinos in a high track density environment like DONUT. In order to measure with high accuracy and high speed, very strict constraints must be satisfied in terms of mechanical precisions, camera speed, image processing power. Recent improvements in this technique are briefly reported

  17. Fermented food for life (CIFSRF Phase 2) | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... and Heifer International (Uganda) will work with the Yoba for Life Foundation and No Money No Cry Films to introduce the sachets to 150 new suppliers. The team will evaluate different business models to turn small and medium farmers into dairy processors, and anticipates the creation of more than 1,000 profitable new ...

  18. Formulation and stability of topical water in oil emulsion containing ...

    African Journals Online (AJOL)

    (DOAJ), African Journal Online, Bioline International, Open-J-Gate and Pharmacy Abstracts. INTRODUCTION. Emulsions are widely used in the ... increased customer acceptance for such products [11]. Corn silk refers to the brownish, thread ... The reaction mixtures were stirred and kept for incubation at 37 oC in the dark.

  19. An Emulsion System Based on a Chip Polymerase Chain Reaction

    Directory of Open Access Journals (Sweden)

    Pinfei Yu

    2008-12-01

    Full Text Available In this paper we describe a novel method for detecting many DNA fragments through efficient amplification by using an emulsion system based on “on-chip” PCR instead of conventional multiplex polymerase chain reaction (PCR. During the preparation of on-chip PCR, a set of primers were immobilized on a slide and other sets were in an emulsion system. Different emulsion phase primers and other related PCR components were dispersed in different droplets of the emulsion system, and then, due to the thermal instability of emulsion droplets, they would be released onto the surface of the slide after preheating in the first PCR step. To test the above method, we used plasma DNAs from pregnant women who was carrying a male fetus for gender identification. Four different Y chromosome DNA fragments were selected. Results showed that different DNA fragments could be simultaneously amplified with satisfactory results. It is suggested that a simple, convenient and inexpensive on-chip PCR method has been developed.

  20. Parameters affecting the thermal behaviour of emulsion explosives

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.E.G.; Feng, H.; Mintz, K.J.; Augsten, R.A. [Natural Resources Canada, Ottawa, ON (Canada). Canadian Explosives Research Laboratory

    1999-07-01

    Accelerating rate calorimetry (ARC) and heat flux calorimetry (HFC) were used to study the sensitivity of ammonium nitrate (AN) and emulsion explosives to pressure and various other parameters. The explosives were evaluated in a series of experiments that examined the influence of pressure in both Argon and air environments at 5.4 MPa. Results of the study demonstrated that significantly lower onset temperatures were observed when the ammonium nitrate (AN) explosive was used in air. Results of the ARC study suggested that lower initial temperatures resulted in an elevated onset temperature. Lower onset temperatures observed in the study were attributed to oxidation of the oil phase in the emulsion. Onset temperatures for the AN explosive were lower than rates observed for the emulsion explosives. The size of the samples also influenced onset temperatures in both the ARC and HFC analyses. At heating rates of 0.1 degrees C per minute, the results of heat flux calorimetry revealed a complex exotherm pattern for the emulsion explosive in both Argon and in air. The high pressure of inert gas inhibited and delayed the exothermic reactions for the emulsion explosives. It was concluded that air-oxidative decomposition results in lower onset temperatures that are influenced by higher pressure rates. 8 refs., 3 tabs., 8 figs.

  1. Analysis of Multiallelic CNVs by Emulsion Haplotype Fusion PCR.

    Science.gov (United States)

    Tyson, Jess; Armour, John A L

    2017-01-01

    Emulsion-fusion PCR recovers long-range sequence information by combining products in cis from individual genomic DNA molecules. Emulsion droplets act as very numerous small reaction chambers in which different PCR products from a single genomic DNA molecule are condensed into short joint products, to unite sequences in cis from widely separated genomic sites. These products can therefore provide information about the arrangement of sequences and variants at a larger scale than established long-read sequencing methods. The method has been useful in defining the phase of variants in haplotypes, the typing of inversions, and determining the configuration of sequence variants in multiallelic CNVs. In this description we outline the rationale for the application of emulsion-fusion PCR methods to the analysis of multiallelic CNVs, and give practical details for our own implementation of the method in that context.

  2. Inverse Pickering Emulsions with Droplet Sizes below 500 nm.

    Science.gov (United States)

    Sihler, Susanne; Schrade, Anika; Cao, Zhihai; Ziener, Ulrich

    2015-09-29

    Inverse Pickering emulsions with droplet diameters between 180 and 450 nm, a narrow droplet size distribution, and an outstanding stability were prepared using a miniemulsion technique. Commercially available hydrophilic silica nanoparticles were used to stabilize the emulsions. They were hydrophobized in situ by the adsorption of various neutral polymeric surfactants. The influence of different parameters, such as kind and amount of surfactant as hydrophobizing agent, size and charge of the silica particles, and amount of water in the dispersed phase, as well as the kind of osmotic agent (sodium chloride and phosphate-buffered saline), on the emulsion characteristics was investigated. The systems were characterized by dynamic light scattering, transmission electron microscopy, cryo-scanning electron microscopy (cryo-SEM), thermogravimetric analysis, and semiquantitative attenuated total reflection infrared spectroscopy. Cryo-SEM shows that some silica particles are obviously rendered hydrophilic and form a three-dimensional network inside the droplets.

  3. Report: Potential of nano-emulsions as phytochemical delivery system for food preservation.

    Science.gov (United States)

    Mahmood, Zaffar; Jahangir, Muhammad; Liaquat, Muhammad; Shah, Syed Wasim Ahmad; Khan, Muhammad Mumtaz; Stanley, Roger; D'Arcy, Bruce

    2017-11-01

    Nature is a rich source of bioactive phytochemicals. These plant based compounds have rich scope as antioxidants, antimicrobial compounds and food preservatives and so for long time to be used in meat, fruits, vegetables and processed food items, either as added preservative or as coating material in various food applications, but the major limitation is their limited solubility in a food grade medium. Nano-emulsion is a best choice as a medium having vast area of application. The major advantage of nano-emulsion would be the solubility of a vast group of compounds, due to the presence of water and lipid phases. In this way, nano-emulsions can be proved to be the most suitable candidate as phytochemical delivery system for food preservation. In present article, the use of phytochemicals as potent food preservatives has been reviewed, in context of solubility of phytochemicals in nano-emulsion and applications of food grade nano-emulsions to food systems.

  4. Electromechanical phase transition of a dielectric elastomer tube under internal pressure of constant mass

    Directory of Open Access Journals (Sweden)

    Song Che

    2017-05-01

    Full Text Available The electromechanical phase transition for a dielectric elastomer (DE tube has been demonstrated in recent experiments, where it is found that the unbulged phase gradually changed into bulged phase. Previous theoretical works only studied the transition process under pressure control condition, which is not consistent with the real experimental condition. This paper focuses on more complex features of the electromechanical phase transition under internal pressure of constant mass. We derive the equilibrium equations and the condition for coexistent states for a DE tube under an internal pressure, a voltage through the thickness and an axial force. We find that under mass control condition the voltage needed to maintain the phase transition increases as the process proceeds. We analyze the entire process of electromechanical phase transition and find that the evolution of configurations is also different from that for pressure control condition.

  5. An algorithm for testing of gas distribution phases in the internal combustion engines

    Directory of Open Access Journals (Sweden)

    T. Nicu

    1999-10-01

    Full Text Available A method and algorithm for testing the gas distribution phases of internal combustion engines are proposed. This method allows a way of testing the gas distribution phases, based on direct and continuous measurements of pressure in cylinders and negative pressure in the intake manifold for using in the real time.

  6. Manipulation of light using slanted layer photonic crystals in holographic gelatin emulsions

    Science.gov (United States)

    Yau, Suet Man; Hin Kok, Mang; Tam, Wing Yim

    2008-01-01

    We use slanted layer structures fabricated in holographic gelatin emulsions using a two-beam optical interference to bend light in the bandgap of the layer structures. We demonstrate that light in the visible range, incident normal to the holographic emulsion plate, can be bent so that it is trapped inside the gelatin emulsion by internal reflections and comes out at the edges of the plate using a single-slanted-layer structure. Furthermore, we show that using a double-slanted-layer structure, consisting of two single-slanted-layer structures arranged in a V-shaped configuration, light in the bandgap can make a U-turn inside the gelatin emulsion and come out of the emulsion like a reflection but with the beam displaced from the incident beam by the separation of the two slanted layers. The slanted layer structures may be applicable in steering light in optical circuits and couplers.

  7. Los Angeles International Airport Runway Incursion Studies: Phase III--Center-Taxiway Simulation

    Science.gov (United States)

    Madson, Michael D.

    2004-01-01

    Phase III of the Los Angeles International Airport Runway Incursion Studies was conducted, under an agreement with HNTB Corporation, at the NASA Ames FutureFlight Central (FFC) facility in June 2003. The objective of the study was the evaluation of a new center-taxiway concept at LAX. This study is an extension of the Phase I and Phase II studies previously conducted at FFC. This report presents results from Phase III of the study, in which a center-taxiway concept between runways 25L and 25R was simulated and evaluated. Phase III data were compared objectively against the Baseline data. Subjective evaluations by participating LAX controllers were obtained with regard to workload, efficiency, and safety criteria. To facilitate a valid comparison between Baseline and Phase III data, the same scenarios were used for Phase III that were tested during Phases I and II. This required briefing participating controllers on differences in airport and airline operations between 2001 and today.

  8. Isotachophoresis with emulsions

    Science.gov (United States)

    Goet, G.; Baier, T.; Hardt, S.; Sen, A. K.

    2013-01-01

    An experimental study on isotachophoresis (ITP) in which an emulsion is used as leading electrolyte (LE) is reported. The study aims at giving an overview about the transport and flow phenomena occurring in that context. Generally, it is observed that the oil droplets initially dispersed in the LE are collected at the ITP transition zone and advected along with it. The detailed behavior at the transition zone depends on whether or not surfactants (polyvinylpyrrolidon, PVP) are added to the electrolytes. In a system without surfactants, coalescence is observed between the droplets collected at the ITP transition zone. After having achieved a certain size, the droplets merge with the channel walls, leaving an oil film behind. In systems with PVP, coalescence is largely suppressed and no merging of droplets with the channel walls is observed. Instead, at the ITP transition zone, a droplet agglomerate of increasing size is formed. In the initial stages of the ITP experiments, two counter rotating vortices are formed inside the terminating electrolyte. The vortex formation is qualitatively explained based on a hydrodynamic instability triggered by fluctuations of the number density of oil droplets. PMID:24404037

  9. Stability of bisphenol A (BPA) in oil-in water emulsions under riboflavin photosensitization.

    Science.gov (United States)

    Jang, Eun Yeong; Park, Chan Uk; Kim, Mi-Ja; Lee, JaeHwan

    2012-08-01

    Effects of riboflavin photosensitization on the degradation of bisphenol A (BPA) were determined in oil-in-water (O/W) emulsions containing ethylenediaminetetraacetic acid (EDTA) or sodium azide, which are a metal chelator or a singlet oxygen quencher, respectively. Also, the distribution of BPA between the continuous and dispersed phases in O/W emulsions was analyzed by high-performance liquid chromatography (HPLC). The concentration of BPA in O/W emulsions significantly decreased by 38.6% after 2 h under visible light irradiation and in the presence of riboflavin (P riboflavin photosensitization (P riboflavin photodegradation in O/W emulsions. Concentration of BPA, an endocrine disrupting chemical, was decreased significantly in oil-in-water emulsions under riboflavin and visible light irradiation. BPA in continuous aqueous phase was major target of riboflavin photosensitization. However, BPA was distributed more densely in lipid phase and more protected from riboflavin photosensitized O/W emulsions. This study can help to decrease the level of BPA in foods made of O/W emulsions containing riboflavin, which could be displayed under visible light irradiation. © 2012 Institute of Food Technologists®

  10. New liquid-liquid extraction apparatus, 'emulsion-flow' extractor

    International Nuclear Information System (INIS)

    Naganawa, Hirochika

    2017-01-01

    A new liquid-liquid extraction method, called the 'emulsion-flow' method, has recently been developed at Japan Atomic Energy Agency (JAEA). The emulsion-flow method, where low cost, simplicity, high efficiency, compactness, safety, and eco-friendly go together, has attracted attention, and has been expected to bring innovation to liquid-liquid extraction technologies. An apparatus based on the emulsion-flow method can actualize very efficient liquid-liquid extraction with its high two-phase mixing ability to an emulsion by spraying micrometer-sized oil droplets into a counter-current aqueous solution by only solution sending. Meanwhile, at the same time, the emulsion produced in the apparatus disappears rapidly and perfectly by drastically changing the cross-section where liquid droplets pass through in its vessel structure. Such a rapid and perfect phase separation can realize a high processing speed with a small-sized apparatus. Compared with conventional industrial apparatuses, an emulsion-flow apparatus successfully combines the lowest cost superior to a spray column and the highest performance (the highest efficiency and the highest processing speed) comparable to a centrifugal extractor. Furthermore, the emulsion-flow method can also be used for collecting particulate components by utilizing their aggregation onto a liquid-liquid interface and for purifying water polluted by oil with its remarkable phase-separating ability. (author)

  11. The dynamic influence of cells on the formation of stable emulsions in organic-aqueous biotransformations.

    Science.gov (United States)

    Collins, Jonathan; Grund, Marcel; Brandenbusch, Christoph; Sadowski, Gabriele; Schmid, Andreas; Bühler, Bruno

    2015-07-01

    Emulsion stability plays a crucial role for mass transfer and downstream processing in organic-aqueous bioprocesses based on whole microbial cells. In this study, emulsion stability dynamics and the factors determining them during two-liquid phase biotransformation were investigated for stereoselective styrene epoxidation catalyzed by recombinant Escherichia coli. Upon organic phase addition, emulsion stability rapidly increased correlating with a loss of solubilized protein from the aqueous cultivation broth and the emergence of a hydrophobic cell fraction associated with the organic-aqueous interface. A novel phase inversion-based method was developed to isolate and analyze cellular material from the interface. In cell-free experiments, a similar loss of aqueous protein did not correlate with high emulsion stability, indicating that the observed particle-based emulsions arise from a convergence of factors related to cell density, protein adsorption, and bioreactor conditions. During styrene epoxidation, emulsion destabilization occurred correlating with product-induced cell toxification. For biphasic whole-cell biotransformations, this study indicates that control of aqueous protein concentrations and selective toxification of cells enables emulsion destabilization and emphasizes that biological factors and related dynamics must be considered in the design and modeling of respective upstream and especially downstream processes.

  12. Changes in the Characteristics of Water-in-Oil-based High Internal ...

    African Journals Online (AJOL)

    Changes in the Characteristics of Water-in-Oil-based High Internal Phase Emulsion Containing Moringa Leaves Extract at Various Storage Conditions. ... Conclusion: Moringa HIPE showed stability and can be guided exclusively to protect skin against ultraviolet radiation-mediated oxidative damage. Keywords: Moringa ...

  13. Kaolinite and Silica Dispersions in Low-Salinity Environments: Impact on a Water-in-Crude Oil Emulsion Stability

    Directory of Open Access Journals (Sweden)

    Vladimir Alvarado

    2011-10-01

    Full Text Available This research aims at providing evidence of particle suspension contributions to emulsion stability, which has been cited as a contributing factor in crude oil recovery by low-salinity waterflooding. Kaolinite and silica particle dispersions were characterized as functions of brine salinity. A reference aqueous phase, representing reservoir brine, was used and then diluted with distilled water to obtain brines at 10 and 100 times lower Total Dissolved Solid (TDS. Scanning Electron Microscope (SEM and X-ray Diffraction (XRD were used to examine at the morphology and composition of clays. The zeta potential and particle size distribution were also measured. Emulsions were prepared by mixing a crude oil with brine, with and without dispersed particles to investigate emulsion stability. The clay zeta potential as a function of pH was used to investigate the effect of particle charge on emulsion stability. The stability was determined through bottle tests and optical microscopy. Results show that both kaolinite and silica promote emulsion stability. Also, kaolinite, roughly 1 mm in size, stabilizes emulsions better than larger clay particles. Silica particles of larger size (5 µm yielded more stable emulsions than smaller silica particles do. Test results show that clay particles with zero point of charge (ZPC at low pH become less effective at stabilizing emulsions, while silica stabilizes emulsions better at ZPC. These result shed light on emulsion stabilization in low-salinity waterflooding.

  14. Microstructure and rheology of particle stabilized emulsions: Effects of particle shape and inter-particle interactions.

    Science.gov (United States)

    Katepalli, Hari; John, Vijay T; Tripathi, Anubhav; Bose, Arijit

    2017-01-01

    Using fumed and spherical silica particles of similar hydrodynamic size, we investigated the effects of particle shape and inter-particle interactions on the formation, stability and rheology of bromohexadecane-in-water Pickering emulsions. The interparticle interactions were varied from repulsive to attractive by modifying the salt concentration in the aqueous phase. Optical microscope images revealed smaller droplet sizes for the fumed silica stabilized emulsions. All the emulsions remained stable for several weeks. Cryo-SEM images of the emulsion droplets showed a hexagonally packed single layer of particles at oil-water interfaces in emulsions stabilized with silica spheres, irrespective of the nature of the inter-particle interactions. Thus, entropic, excluded volume interactions dominate the fate of spherical particles at oil-water interfaces. On the other hand, closely packed layers of particles were observed at oil-water interfaces for the fumed silica stabilized emulsions for both attractive and repulsive interparticle interactions. At the high salt concentrations, attractive inter-particles interactions led to aggregation of fumed silica particles, and multiple layers of these particles were then observed on the droplet surfaces. A network of fumed silica particles was also observed between the emulsion droplets, suggesting that enthalpic interactions are responsible for the determining particle configurations at oil-water interfaces as well as in the aqueous phase. Steady shear viscosity measurements over a range of shear stresses, as well as oscillatory shear measurements at 1Hz confirm the presence of a network in fumed silica suspensions and emulsions, and the lack of such a network when spherical particles are used. The fractal structure of fumed silica leads to several contact points and particle interlocking in the water as well as on the bromohexadecane-water interfaces, with corresponding effects on the structure and rheology of the emulsions

  15. Macroporous Polymers with Hierarchical Pore Structure from Emulsion Templates Stabilised by Both Particles and Surfactants.

    Science.gov (United States)

    Wong, Ling L Ching; Ikem, Vivian O; Menner, Angelika; Bismarck, Alexander

    2011-10-04

    Inspired by natural porous materials, such as wood, bamboo and spongy bone consisting of individual structural units that are hierarchically arranged to optimise mechanical properties such as strength and toughness, synthetic macroporous polymers with enhanced physical properties were created by emulsion templating. Hierarchical poly(merised) high internal phase emulsions (HIPE) were created from HIPEs stabilised simultaneously by particles and a surfactant. In these HIPEs, surfactant stabilised and particle stabilised water droplets coexist, which upon polymerisation of the minority oil phase gives rise to macroporous polymers with a hierarchical pore structure. An improvement of the mechanical properties of our hierarchically structured macroporous polymers at equal porosity was observed, due to a more efficient packing of pores in a configuration that improves mechanical strength despite the presence of interconnecting pore throats. Moreover, the permeability of the hierarchically structured polyHIPEs are exceeding those measured for conventional polyHIPEs made from surfactant only stabilised HIPEs. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Emulsion liquid membrane for selective extraction of bismuth from nitrate medium

    International Nuclear Information System (INIS)

    Mokhtari, Bahram; Pourabdollah, Kobra

    2013-01-01

    The novelty of this work is the selective extraction of bismuth ions from nitrate medium by emulsion liquid membrane. Di(2-ethylhexyl)phosphoric acid was used as extractant of bismuth ions from nitrate medium by emulsion liquid membrane, and Triton X-100 was used as the biodegradable surfactant in n-pentanol n-pentanol bulk membrane. The extraction of bismuth ions was evaluated by the yield of extraction. The experimental parameters were evaluated and were optimized. They included the ratio of di(2-ethylhexyl)phosphoric acid concentration to the concentration of /Triton X-100 concentration (1.0 : 0.5% w/w), nature of diluents (n-pentanol), nature and concentration of the stripping solution (sulfuric acid, 0.5M), stirring speed (1,800 rpm) and equilibrium time of extraction (20min), initial feed solution of bismuth (350 ppm) and the volume ratio of the internal stripping phase to the membrane phase (14 times). The experimental parameters of kinetic extraction revealed that the bismuth ions were extracted at 100% 97%

  17. Emulsion liquid membrane for selective extraction of bismuth from nitrate medium

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtari, Bahram; Pourabdollah, Kobra [Islamic Azad University, Shahreza (Iran, Islamic Republic of)

    2013-07-15

    The novelty of this work is the selective extraction of bismuth ions from nitrate medium by emulsion liquid membrane. Di(2-ethylhexyl)phosphoric acid was used as extractant of bismuth ions from nitrate medium by emulsion liquid membrane, and Triton X-100 was used as the biodegradable surfactant in n-pentanol n-pentanol bulk membrane. The extraction of bismuth ions was evaluated by the yield of extraction. The experimental parameters were evaluated and were optimized. They included the ratio of di(2-ethylhexyl)phosphoric acid concentration to the concentration of /Triton X-100 concentration (1.0 : 0.5% w/w), nature of diluents (n-pentanol), nature and concentration of the stripping solution (sulfuric acid, 0.5M), stirring speed (1,800 rpm) and equilibrium time of extraction (20min), initial feed solution of bismuth (350 ppm) and the volume ratio of the internal stripping phase to the membrane phase (14 times). The experimental parameters of kinetic extraction revealed that the bismuth ions were extracted at 100% 97%.

  18. Mango butter emulsion gels as cocoa butter equivalents: physical, thermal, and mechanical analyses.

    Science.gov (United States)

    Sagiri, Sai S; Sharma, Vijeta; Basak, Piyali; Pal, Kunal

    2014-11-26

    The search for cocoa butter equivalents in food and pharmaceutical industries has been gaining importance. In the present study, mango butter was explored as cocoa butter equivalent. Aqueous gelatin solution (20% w/w) containing cocoa butter and mango butter water-in-oil (fat) type emulsion gels were prepared by hot emulsification method. XRD and DSC melting profiles suggested the presence of unstable polymorphic forms (α and β') of fats in the emulsion gels. The crystal size and solid fat content analyses suggested that the presence of aqueous phase might have hindered the transformation of unstable polymorphic forms to stable polymorphic form (β) in the emulsion gels. Fat crystals in the emulsion gels were formed by instantaneous nucleation via either uni- or bidimensional growth (Avrami analysis). The viscoelastic nature of the emulsion gels was evaluated by modified Peleg's analysis (stress relaxation study). Results inferred that the physical, thermal, and mechanical properties of mango butter emulsion gels are comparable to those of cocoa butter emulsion gels. On the basis of preliminary studies, it was suggested that the mango butter emulsion gels may have potential to be used as cocoa butter equivalents.

  19. Efficacy and safety of a nano-emulsion gel formulation of adapalene 0.1% and clindamycin 1% combination in acne vulgaris: A randomized, open label, active-controlled, multicentric, phase IV clinical trial

    Directory of Open Access Journals (Sweden)

    Siva Prasad

    2012-01-01

    Full Text Available Background: Acne vulgaris is a very common skin disease with a significant detrimental effect on the quality of life of the patients. Aims: To assess the comparative efficacy and safety of a nano-emulsion gel formulation of adapalene and clindamycin combination with its conventional formulation in the treatment of acne vulgaris of the face. It was a prospective, randomized, open label, active-controlled, multicentric, clinical trial. Methods: Eligible patients suffering from acne vulgaris of the face were randomized to receive once-daily treatment with a nano-emulsion gel or conventional gel formulation of adapalene 0.1% and clindamycin (as phosphate 1% combination for 12 weeks. Total, inflammatory and noninflammatory lesion counts, with grading of acne severity were carried out on a monthly basis. Safety assessments were done to determine the comparative local and systemic tolerability. Two-tailed significance testing was carried out with appropriate statistical tests, and P-values < 0.05 were considered as significant. Results: 209/212 patients enrolled in the study were eligible for efficacy and safety assessments in both nano-emulsion gel (118/119 patients and conventional gel (91/93 patients groups. Significantly better reductions in total (79.7% vs. 62.7%, inflammatory (88.7% vs. 71.4% and noninflammatory (74.9% vs. 58.4% lesions were reported with the nano-emulsion gel as compared to the conventional gel (P < 0.001 for all. Mean acne severity score also reduced significantly more with the nano-emulsion formulation (1.9 ± 0.9 vs. 1.4 ± 1.0; P < 0.001 than the comparator. Significantly lower incidence and lesser intensity of adverse events like local irritation (4.2% vs. 19.8%; P < 0.05 and erythema (0.8% vs. 9.9%; P < 0.05 were recorded with the nano-emulsion gel. Conclusions: The nano-emulsion gel formulation of adapalene and clindamycin combination appears to be more efficacious and better tolerated than the conventional formulation

  20. Multiple emulsions containing amazon oil: açaí oil (Euterpe oleracea

    Directory of Open Access Journals (Sweden)

    Márcio Ferrari

    2011-08-01

    Full Text Available The aim of this work was to formulate O/W/O multiple emulsions containing açaí oil as a model system and to evaluate their physical stability and in vivo Sun Protection Factor (SPF. Multiple emulsions are complex dispersion systems, known also as, "emulsions of emulsions". These emulsion systems, have significant potential in the cosmetic industry. Euterpe oleracea Mart., Arecaceae, popularly known in Brazil as "açaí", is an economically important plant. Açaí oil has been used as antioxidant and as anti-inflammatory activities. The multiple emulsions were prepared using a two-step procedure. The investigated formulations were characterized and their stability over time was evaluated by preliminary and accelerated stability. O/W/O multiple emulsions containing the same concentration of sunscreens with and without açaí oil were evaluated by the International Sun Protection Factor Test Method. The samples containing 70% (w/w of primary emulsion, 5% (w/w PEG-30-dipolyhydroxystearate, 10% (w/w of açaí oil and 5% (w/w of sucrose polybehenate have been found to be stable. The rheological measurements revealed that the samples exhibited non-Newtonian pseudoplastic flow behavior and thixotropy. To conclude, no statistical difference could be observed on the in vivo SPF to both multiple systems with or without açaí oil.

  1. Propagation of the Semidiurnal Internal Tide: Phase Velocity Versus Group Velocity

    Science.gov (United States)

    Zhao, Zhongxiang

    2017-12-01

    The superposition of two waves of slightly different wavelengths has long been used to illustrate the distinction between phase velocity and group velocity. The first-mode M2 and S2 internal tides exemplify such a two-wave model in the natural ocean. The M2 and S2 tidal frequencies are 1.932 and 2 cycles per day, respectively, and their superposition forms a spring-neap cycle in the semidiurnal band. The spring-neap cycle acts like a wave, with its frequency, wave number, and phase being the differences of the M2 and S2 internal tides. The spring-neap cycle and energy of the semidiurnal internal tide propagate at the group velocity. Long-range propagation of M2 and S2 internal tides in the North Pacific is observed by satellite altimetry. Along a 3,400 km beam spanning 24°-54°N, the M2 and S2 travel times are 10.9 and 11.2 days, respectively. For comparison, it takes the spring-neap cycle 21.1 days to travel over this distance. Spatial maps of the M2 phase velocity, the S2 phase velocity, and the group velocity are determined from phase gradients of the corresponding satellite observed internal tide fields. The observed phase and group velocities agree with theoretical values estimated using the World Ocean Atlas 2013 annual-mean ocean stratification.

  2. Stabilized emulsions formed on the basis of silicic acid in extraction systems with tri-n-butyl phosphate

    International Nuclear Information System (INIS)

    Nikipelov, B.V.; Andreev, V.I.; Markov, S.G.; Moshkov, M.M.; Kokina, S.A.; Goncharuk, L.V.

    1983-01-01

    Conditions resulting in the ppearance of stabilized emulsions in the process of contact'ng of the extraction mixture TBP-diluent with aqueous nitric cid solutions, containing dissolved silicic acid, have bee' studied. It is shown that a stabilized emulsion appears following the TBP n-interaction with intermediate forms of polys'licic acid insoluble in the organic phase. The main factors esponsible for the formation of stabilized emulsions in the e traction systems are revealed. It is established that, when c rbon tetrachloride, chloroform, benzene are used as diluents, th intensity of the stabilized emulsion formation decreases con iderably

  3. Emulsion polymerization with high energy radiation

    International Nuclear Information System (INIS)

    Stannett, V.T.; Stahel, E.P.

    1992-01-01

    High energy radiation, particularly that of cobalt-60 or caesium-137 gamma-rays, provides in principle an ideal initiator for emulsion polymerization. The high free radical yields from the radiolysis of the aqueous phase combined with the high kinetic chain lengths associated with emulsion polymerization lead to a highly effective utilization of the radiation. There are other important advantages compared with the use of chemical initiators such as potassium persulfate. These are outlined in the chapter, together with some attendant disadvantages. Radiation-induced initiation is temperature independent, and low temperature polymerizations can be conducted with ease. Monomers that mainly terminate their growing chains by chain transfer to monomer give higher molecular weights at lower temperatures. Industrially, vinyl acetate is an important example of such a monomer, and it has been studied using radiation initiation. Both laboratory and pilot plant studies have been carried out and reported. The results are summarized in this chapter. Styrene is the classical example of a material that under a number of conditions closely obeys the so-called ideal Smith-Ewart kinetics. It has been found that under similar conditions but substituting radiation for potassium persulfate as the initiator, ideal kinetics were closely followed. Most of the conventional and some non-standard vinyl and diene monomers have been studied to some extent with radiation-initiated polymerizations in emulsion. To conserve space however, this chapter presents and discusses the results obtained only with styrene and vinyl acetate, both in laboratory and pilot plant investigations. Other monomers and special situations are referenced either directly or to the other available reviews. (orig.)

  4. Sustained delivery of salbutamol and beclometasone from spray-dried double emulsions.

    Science.gov (United States)

    Learoyd, Tristan P; Burrows, Jane L; French, Eddie; Seville, Peter C

    2010-01-01

    The sustained delivery of multiple agents to the lung offers potential benefits to patients. This study explores the preparation of highly respirable dual-loaded spray-dried double emulsions. Spray-dried powders were produced from water-in-oil-in-water (w/o/w) double emulsions, containing salbutamol sulphate and/or beclometasone dipropionate in varying phases. The double emulsions contained the drug release modifier polylactide co-glycolide (PLGA 50 : 50) in the intermediate organic phase of the original micro-emulsion and low molecular weight chitosan (Mwemulsion stabilizer) and leucine (aerosolization enhancer) in the tertiary aqueous phase. Following spray-drying resultant powders were physically characterized: with in vitro aerosolization performance and drug release investigated using a Multi-Stage Liquid Impinger and modified USP II dissolution apparatus, respectively. Powders generated were of a respirable size exhibiting emitted doses of over 95% and fine particle fractions of up to 60% of the total loaded dose. Sustained drug release profiles were observed during dissolution for powders containing agents in the primary aqueous and secondary organic phases of the original micro-emulsion; the burst release of agents was witnessed from the tertiary aqueous phase. The novel spray-dried emulsions from this study would be expected to deposit and display sustained release character in the lung.

  5. Micro magnetofluidics: droplet manipulation of double emulsions based on paramagnetic ionic liquids.

    Science.gov (United States)

    Misuk, Viktor; Mai, Andreas; Giannopoulos, Konstantinos; Alobaid, Falah; Epple, Bernd; Loewe, Holger

    2013-12-07

    The ability to control and manipulate discrete fluid droplets by magnetic fields offers new opportunities in microfluidics. A surfactant-free and easy to realize technique for the continuous generation of double emulsion droplets, composed of an organic solvent and a paramagnetic ionic liquid, is applied. The inner phase of the emulsion droplet consists of imidazolium-based ionic liquids with either iron, manganese, nickel or dysprosium containing anions which provide paramagnetic behaviour. The double emulsion droplets are dispersed in a continuous phase of FC-40. All substances - the organic phase, the paramagnetic ionic liquid and the continuous phase -are immiscible. The magnetic properties of ionic liquids allow, through the influence of external magnetic fields, the manipulation of individual emulsion droplets such as capture and release, rotation and distortion. Arrays of magnets allow a coalescence of emulsion droplets and their subsequent mixing by flowing through an alternating permanent magnetic field. In addition, the double emulsion droplets can be split and reunified, or continuously separated into their original phases.

  6. Microwave selective heating for size effect of water droplet in W/O emulsion with sorbitan fatty acid monostearate surfactant

    International Nuclear Information System (INIS)

    Sumi, Takuya; Horikoshi, Satoshi

    2015-01-01

    A stable water/oil (W/O) emulsion was prepared by adjustment with sorbitan fatty acid monoester surfactants. The prepared W/O emulsion was stable for 60 min in the atmosphere; however, the formation of non-uniform water droplets in the height of the emulsion in the quartz tube reactor were observed by the backscattering measurements with an infrared laser at 850 nm. The increase of temperature under microwave irradiation was influenced sensitively by the position of those water droplets. Those results were caused from the size and concentration of water droplets in the W/O emulsion. On the other hand, selective heating of the water droplets caused heating of the entire W/O emulsion, although the temperature difference between the water droplets and the oil phase was 20 °C. - Graphical abstract: The feature of a selective heating phenomenon in a W/O emulsion under microwave irradiation was investigated both practically and theoretically. Temperature profiles of emulsions stabilized with different sorbitan fatty acid monoester surfactants indicated that a smaller size distribution of water droplets leads to a higher heating rate. Moreover, computational studies suggested that water droplets in oil are 20 °C higher than the organic phase. - Highlights: • The microscopic heating features of microwaves in a W/O emulsion were examined. • The microwave heating behaviors reflected the properties of water droplets. • The heat convection process in a W/O emulsion was studied by a theoretical approach

  7. Dynamics of Encapsulation and Controlled Release Systems Based on Water-in-Water Emulsions: Negligible Surface Rheology

    NARCIS (Netherlands)

    Sagis, L.M.C.

    2008-01-01

    A nonequilibrium thermodynamic model based on the interfacial transport phenomena (ITP) formalism was used to study deformation¿relaxation behavior of water-in-water emulsions. The ITP formalism allows us to describe all water-in-water emulsions with one single theory. Phase-separated biopolymer

  8. Counter current 'emulsion flow' extractor for continuous liquid-liquid extraction from suspended solutions

    International Nuclear Information System (INIS)

    Yanase, Nobuyuki; Naganawa, Hirochika; Nagano, Tetsushi; Noro, Junji

    2011-01-01

    A single current 'emulsion flow' liquid-liquid extraction apparatus has a head with a number of holes from which micrometer-sized droplets of an aqueous phase spout into an organic phase to mix the two liquid phases. For practical use, however, a fatal problem can occur when particulate components in the aqueous phase plug the holes. In the present study, we have succeeded in solving the problem by applying a counter current-type emulsion flow extractor where micrometer-sized droplets of the organic phase are generated. (author)

  9. HEAVY-OIL PRODUCTION USING EMULSION FLOODING

    African Journals Online (AJOL)

    user

    liquid and ρ2 is the density of liquid. 3. RESULTS AND DISCUSSION. 3.1 Centrifugation Analysis. The emulsion stability is analysed based on the less percentage of water separated. In other hand, the greater stability of emulsion shows the smaller percentage of water separated from the oil-in-water emulsions. The stability ...

  10. Emulsion properties of sunflower (Helianthus annuus) proteins

    NARCIS (Netherlands)

    Gonzalez-Perez, S.; Koningsveld, van G.A.; Vereijken, J.M.; Merck, K.B.; Gruppen, H.; Voragen, A.G.J.

    2005-01-01

    Emulsions were made with sunflower protein isolate (SI), helianthinin, and sunflower albumins (SFAs). Emulsion formation and stabilization were studied as a function of pH and ionic strength and after heat treatment of the proteins. The emulsions were characterized with respect to average droplet

  11. Study on the Stability of DeoxyArbutin in an Anhydrous Emulsion Systemy

    Directory of Open Access Journals (Sweden)

    Chiu-Wen Chen

    2011-09-01

    Full Text Available The skin-whitening agent, deoxyArbutin, is a potent tyrosinase inhibitor that is safer than hydroquinone and arbutin. However, it is thermolabile in aqueous solutions, where it decomposes to hydroquinone. Pharmaceutical and cosmetic emulsions are normally oil-in-water (o/w or water-in-oil (w/o systems; however, emulsions can be formulated with no aqueous phase to produce an anhydrous emulsion system. An anhydrous emulsion system could offer a stable vehicle for compounds that are sensitive to hydrolysis or oxidation. Therefore, to enhance the stability of deoxyArbutin in formulations, we chose the polyol-in-silicone, anhydrous emulsion system as the basic formulation for investigation. The quantity of deoxyArbutin and the accumulation of hydroquinone in both hydrous and anhydrous emulsions at various temperatures were analyzed through an established high performance liquid chromatographic (HPLC method. The results indicated that water increased the decomposition of deoxyArbutin in the formulations and that the polyol-in-silicone, oil-based, anhydrous emulsion system provided a relatively stable surrounding for the deoxyArbutin that delayed its degradation at 25 °C and 45 °C. Moreover, the composition of the inner hydrophilic phase, containing different amounts of glycerin and propylene glycol, affected the stability of deoxyArbutin. Thus, these results will be beneficial when using deoxyArbutin in cosmetics and medicines in the future.

  12. Solvent-free formation of hydroxyapatite coated biodegradable particles via nanoparticle-stabilized emulsion route

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Masahiro, E-mail: okada-m@cc.osaka-dent.ac.jp [Department of Biomaterials, Osaka Dental University, 8-1 Kuzuha-Hanazono, Hirakata, Osaka 573-1121 (Japan); Fujii, Syuji, E-mail: s.fujii@chem.oit.ac.jp [Department of Applied Chemistry, Osaka Institute of Technology 5-16-1 Ohmiya, Asahi, Osaka 535-8585 (Japan); Nishimura, Taiki; Nakamura, Yoshinobu [Department of Applied Chemistry, Osaka Institute of Technology 5-16-1 Ohmiya, Asahi, Osaka 535-8585 (Japan); Takeda, Shoji [Department of Biomaterials, Osaka Dental University, 8-1 Kuzuha-Hanazono, Hirakata, Osaka 573-1121 (Japan); Furuzono, Tsutomu [Department of Biomedical Engineering, School of Biology-Oriented Science and Technology, Kinki University, 930 Nishi-Mitani, Kinokawa, Wakayama 649-6493 (Japan)

    2012-12-01

    Highlights: Black-Right-Pointing-Pointer Hydroxyapatite (HAp) nanoparticles stabilized polymer melt-in-water emulsions without any molecular surfactants. Black-Right-Pointing-Pointer Interaction between polymer and HAp played a crucial role. Black-Right-Pointing-Pointer HAp-coated polymer particles were obtained from the emulsions without any organic solvents. - Abstract: Hydroxyapatite (HAp) nanoparticle-coated biodegradable polymer particles were fabricated from a nanoparticle-stabilized emulsion in the absence of any molecular surfactants or organic solvents. First, a polymer melt-in-water emulsion was prepared by mixing a water phase containing nanosized HAp particles as a particulate emulsifier and an oil phase consisting of poly({epsilon}-caprolactone) (PCL) or poly(L-lactide-co-{epsilon}-caprolactone) (P(LLA-CL)) above its melting point. It was clarified that the interaction between ester/carboxyl groups of the polymers and the HAp nanoparticles at the polymer-water interface played a crucial role to prepare the nanoparticle-stabilized emulsion. The HAp nanoparticle-coated biodegradable polymer particle (a polymer solid-in-water emulsion) was fabricated by cooling the emulsion. The particle morphology and particle size were evaluated using scanning electron microscope.

  13. Study on the Stability of DeoxyArbutin in an Anhydrous Emulsion System

    Science.gov (United States)

    Lin, Chih-Chien; Yang, Chao-Hsun; Chang, Nai-Fang; Wu, Pey-Shiuan; Chen, Yi-Shyan; Lee, Shu-Mei; Chen, Chiu-Wen

    2011-01-01

    The skin-whitening agent, deoxyArbutin, is a potent tyrosinase inhibitor that is safer than hydroquinone and arbutin. However, it is thermolabile in aqueous solutions, where it decomposes to hydroquinone. Pharmaceutical and cosmetic emulsions are normally oil-in-water (o/w) or water-in-oil (w/o) systems; however, emulsions can be formulated with no aqueous phase to produce an anhydrous emulsion system. An anhydrous emulsion system could offer a stable vehicle for compounds that are sensitive to hydrolysis or oxidation. Therefore, to enhance the stability of deoxyArbutin in formulations, we chose the polyol-in-silicone, anhydrous emulsion system as the basic formulation for investigation. The quantity of deoxyArbutin and the accumulation of hydroquinone in both hydrous and anhydrous emulsions at various temperatures were analyzed through an established high performance liquid chromatographic (HPLC) method. The results indicated that water increased the decomposition of deoxyArbutin in the formulations and that the polyol-in-silicone, oil-based, anhydrous emulsion system provided a relatively stable surrounding for the deoxyArbutin that delayed its degradation at 25 °C and 45 °C. Moreover, the composition of the inner hydrophilic phase, containing different amounts of glycerin and propylene glycol, affected the stability of deoxyArbutin. Thus, these results will be beneficial when using deoxyArbutin in cosmetics and medicines in the future. PMID:22016637

  14. Solvent-free formation of hydroxyapatite coated biodegradable particles via nanoparticle-stabilized emulsion route

    International Nuclear Information System (INIS)

    Okada, Masahiro; Fujii, Syuji; Nishimura, Taiki; Nakamura, Yoshinobu; Takeda, Shoji; Furuzono, Tsutomu

    2012-01-01

    Highlights: ► Hydroxyapatite (HAp) nanoparticles stabilized polymer melt-in-water emulsions without any molecular surfactants. ► Interaction between polymer and HAp played a crucial role. ► HAp-coated polymer particles were obtained from the emulsions without any organic solvents. - Abstract: Hydroxyapatite (HAp) nanoparticle-coated biodegradable polymer particles were fabricated from a nanoparticle-stabilized emulsion in the absence of any molecular surfactants or organic solvents. First, a polymer melt-in-water emulsion was prepared by mixing a water phase containing nanosized HAp particles as a particulate emulsifier and an oil phase consisting of poly(ε-caprolactone) (PCL) or poly(L-lactide-co-ε-caprolactone) (P(LLA-CL)) above its melting point. It was clarified that the interaction between ester/carboxyl groups of the polymers and the HAp nanoparticles at the polymer–water interface played a crucial role to prepare the nanoparticle-stabilized emulsion. The HAp nanoparticle-coated biodegradable polymer particle (a polymer solid-in-water emulsion) was fabricated by cooling the emulsion. The particle morphology and particle size were evaluated using scanning electron microscope.

  15. The influence of emulsion structure on the Maillard reaction of ghee.

    Science.gov (United States)

    Newton, Angela E; Fairbanks, Antony J; Golding, Matt; Andrewes, Paul; Gerrard, Juliet A

    2015-04-15

    Food systems, such as cream and butter, have an emulsion or emulsion-like structure. When these food emulsions are heated to high temperatures to make products such as ghee, the Maillard reaction forms a range of volatile flavour compounds. The objective of this paper was to unravel the specific influence of emulsion structure on the Maillard reaction pathways that occur during the cooking of ghee using model systems. Switching the dispersed phase from oil to water provided a means of altering the ratios of volatile compounds produced in the cooked samples. The oil-in-water emulsion generated a volatile compound profile similar to that of the fat containing two phase model matrix, whereas the water-in-oil emulsion produced a different ratio of these compounds. The ability to generate different volatile compound profiles through the use of inverted emulsion structures could point to a new avenue for control of the Maillard reaction in high temperature food systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Radiation processing of polymer emulsion, (2)

    International Nuclear Information System (INIS)

    Makuuchi, Keizo; Katakai, Akio; Ito, Hiroshi; Araki, Kunio; Takagi, Toru.

    1980-01-01

    The crosslinking characteristics of hydroxylated acrylic emulsions irradiated with Co-60 γ rays were investigated by measuring the gel fractions of the films baked with melamine resin. Cure response of the irradiated emulsions increased with increasing dose, owing to the crosslinking of the polymers in the emulsion particles by radiation. The irradiated emulsions were crosslinked with melamine resin at lower temperature than the unirradiated emulsion. Crosslinking in the particles by radiation and crosslinking between particles with melamine resin at the elevated temperatures were dependent on the distribution of hydroxyl groups in the particles. Localization of hydroxyl groups near the particle surface did not facilitated both kinds of crosslinking. (author)

  17. Oil-in-water emulsions flow through constricted micro-capillarities

    Energy Technology Data Exchange (ETDEWEB)

    Castillo, Oswaldo Robles; Carvalho, Marcio da Silveira [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil). Dept. of Mechanical Engineering

    2010-07-01

    The effect of the oil concentration and the drop size distribution on the characteristics of the flow of an emulsion through a constricted capillary was experimentally analyzed and quantified by the ratio of the pressure drop of the continuous phase flow to the pressure drop of the emulsion flow, at the same flow rate. The results confirm that the ratio between the capillary constriction diameter and the oil drop size is one of the most important parameters for this flow. For large oil drop size emulsions, the deformation of the drop as it flows through the constriction leads to a high extra pressure drop at low capillary numbers. For small oil drop size emulsions, the extra pressure drop is a function of the viscosity ratio and the disperse phase concentration. (author)

  18. Variation of emulsion stability in sulfuric acid alkylation of isobutane with olefins

    Energy Technology Data Exchange (ETDEWEB)

    Sumanov, V.T.; Ovsyannikov, V.P.

    1982-09-01

    The makeup of the emulsion and its stability are determined to a great degree by the surface and viscosity properties of the acid. Investigates the dependence of emulsion stability on the properties of the acid circulating in the reactor section of an alkylation unit. Finds that as the surface-active substances that accumulate in the acid tend to lower its surface tension, and this in turn tends to disperse the hydrocarbon feedstock in the acid phase and forms a stable emulsion in the vigorously stirred reactor. Points out that as the acid viscosity increases, the segregation of microdrops of hydrocarbons from the acid phase becomes slower in the settling of the emulsion under natural conditions.

  19. Emulsion templated scaffolds with tunable mechanical properties for bone tissue engineering.

    Science.gov (United States)

    Owen, Robert; Sherborne, Colin; Paterson, Thomas; Green, Nicola H; Reilly, Gwendolen C; Claeyssens, Frederik

    2016-02-01

    Polymerised High Internal Phase Emulsions (PolyHIPEs) are manufactured via emulsion templating and exhibit a highly interconnected microporosity. These materials are commonly used as thin membranes for 3D cell culture. This study uses emulsion templating in combination with microstereolithography to fabricate PolyHIPE scaffolds with a tightly controlled and reproducible architecture. This combination of methods produces hierarchical structures, where the microstructural properties can be independently controlled from the scaffold macrostructure. PolyHIPEs were fabricated with varying ratios of two acrylate monomers (2-ethylhexyl acrylate (EHA) and isobornyl acrylate (IBOA)) and varying nominal porosity to tune mechanical properties. Young's modulus, ultimate tensile stress (UTS) and elongation at failure were determined for twenty EHA/IBOA compositions. Moduli ranged from 63.01±9.13 to 0.36±0.04MPa, UTS from 2.03±0.33 to 0.11±0.01MPa and failure strain from 21.86±2.87% to 2.60±0.61%. Selected compositions were fabricated into macro-porous woodpile structures, plasma treated with air or acrylic acid and seeded with human embryonic stem-cell derived mesenchymal progenitor cells (hES-MPs). Confocal and two-photon microscopy confirmed cell proliferation and penetration into the micro- and macro-porous architecture. The scaffolds supported osteogenic differentiation of mesenchymal cells and interestingly, the stiffest IBOA-based scaffolds that were plasma treated with acrylic acid promoted osteogenesis more strongly than the other scaffolds. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. International exchange of emergency phase information and assessments: An aid to national/international decision makers

    International Nuclear Information System (INIS)

    Sullivan, T. J.; Chino, M.; Ehrhardt, J.; Shershakov, V.

    2004-01-01

    This paper discusses a collaborative project (1) to demonstrate the feasibility and benefit of a system seeking early review, in a 'quasi peer review' mode, of nuclear accident plume and dose assessment predictions by four major international nuclear accident emergency response systems before release of calculations to respective national authorities followed by (2) sharing these results with responsible national/international authorities, (3) development of an affordable/accessible system to distribute results to countries without prediction capabilities and (4) utilisation for exercises and collaboration studies. The project exploits Internet browser technology and low-cost PC hardware, incorporates an Internet node, with access control, for depositing a minimal set of XML-based graphics files for presentation in an identical map format. Side-by-side viewing and tele-video conferencing will permit rapid evaluation, data elaboration and recalculation (if necessary) and should produce strong consensus among decision makers. Successful completion affords easy utilisation by national/international organisations and non-nuclear states at risk of trans-boundary incursion. (authors)

  1. Controlling molecular transport in minimal emulsions

    Science.gov (United States)

    Gruner, Philipp; Riechers, Birte; Semin, Benoît; Lim, Jiseok; Johnston, Abigail; Short, Kathleen; Baret, Jean-Christophe

    2016-01-01

    Emulsions are metastable dispersions in which molecular transport is a major mechanism driving the system towards its state of minimal energy. Determining the underlying mechanisms of molecular transport between droplets is challenging due to the complexity of a typical emulsion system. Here we introduce the concept of `minimal emulsions', which are controlled emulsions produced using microfluidic tools, simplifying an emulsion down to its minimal set of relevant parameters. We use these minimal emulsions to unravel the fundamentals of transport of small organic molecules in water-in-fluorinated-oil emulsions, a system of great interest for biotechnological applications. Our results are of practical relevance to guarantee a sustainable compartmentalization of compounds in droplet microreactors and to design new strategies for the dynamic control of droplet compositions.

  2. Radiation processing of polymer emulsion, (1)

    International Nuclear Information System (INIS)

    Makuuchi, Keizo; Araki, Kunio; Takagi, Toru.

    1978-01-01

    Feasibility of radiation processing was investigated to prepare the emulsion which forms a good water resistant film. Polyethylacrylate emulsion was prepared by γ-ray and conventional catalytic (ammonium persulfate) emulsion polymerization at various concentrations of emulsifier. Polymerization stability of γ-ray method was higher than that of catalytic method at low concentration of emulsifier. However, attempts of emulsifier-free polymerization by γ-ray were unsuccessful. Water resistance of the γ-ray emulsion film, measured by water absorption, was very good because of less electrolyte in the emulsion. Irradiation of the emulsion produced by catalytic method improved the water resistance of the film. This was attributed to crosslinking of polyethylacrylate in polymer particles by irradiation of the emulsion. (auth.)

  3. Initiating a New Research Phase in the Field of International Entrepreneurship

    DEFF Research Database (Denmark)

    Coviello, Nicole; Tanev, Stoyan

    2017-01-01

    In a recent publication, Nicole Coviello (2015) emphasized the need to re-think existing research on international entrepreneurship and, more specifically, research on born-global firms. She pointed out that the main value of a critical review lies in initiating a new research phase focusing...... be of relevance for new technology firms aiming at an international or global engagement from their very inception....

  4. Optimization of folic acid nano-emulsification and encapsulation by maltodextrin-whey protein double emulsions.

    Science.gov (United States)

    Assadpour, Elham; Maghsoudlou, Yahya; Jafari, Seid-Mahdi; Ghorbani, Mohammad; Aalami, Mehran

    2016-05-01

    Due to susceptibility of folic acid like many other vitamins to environmental and processing conditions, it is necessary to protect it by highly efficient methods such as micro/nano-encapsulation. Our aim was to prepare and optimize real water in oil nano-emulsions containing folic acid by a low energy (spontaneous) emulsification technique so that the final product could be encapsulated within maltodextrin-whey protein double emulsions. A non ionic surfactant (Span 80) was used for making nano-emulsions at three dispersed phase/surfactant ratios of 0.2, 0.6, and 1.0. Folic acid content was 1.0, 2.0, and 3.0mg/mL of dispersed phase by a volume fraction of 5.0, 8.5, and 12%. The final optimum nano-emulsion formulation with 12% dispersed phase, a water to surfactant ratio of 0.9 and folic acid content of 3mg/mL in dispersed phase was encapsulated within maltodextrin-whey protein double emulsions. It was found that the emulsification time for preparing nano-emulsions was between 4 to 16 h based on formulation variables. Droplet size decreased at higher surfactant contents and final nano-emulsions had a droplet size<100 nm. Shear viscosity was higher for those formulations containing more surfactant. Our results revealed that spontaneous method could be used successfully for preparing stable W/O nano-emulsions containing folic acid. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Homogenization of linear viscoelastic three phase media: internal variable formulation versus full-field computation

    International Nuclear Information System (INIS)

    Blanc, V.; Barbie, L.; Masson, R.

    2011-01-01

    Homogenization of linear viscoelastic heterogeneous media is here extended from two phase inclusion-matrix media to three phase inclusion-matrix media. Each phase obeying to a compressible Maxwellian behaviour, this analytic method leads to an equivalent elastic homogenization problem in the Laplace-Carson space. For some particular microstructures, such as the Hashin composite sphere assemblage, an exact solution is obtained. The inversion of the Laplace-Carson transforms of the overall stress-strain behaviour gives in such cases an internal variable formulation. As expected, the number of these internal variables and their evolution laws are modified to take into account the third phase. Moreover, evolution laws of averaged stresses and strains per phase can still be derived for three phase media. Results of this model are compared to full fields computations of representative volume elements using finite element method, for various concentrations and sizes of inclusion. Relaxation and creep test cases are performed in order to compare predictions of the effective response. The internal variable formulation is shown to yield accurate prediction in both cases. (authors)

  6. Direct uranium extraction from dihydrate and hemi-dihydrate wet process phosphoric acids by liquid emulsion membrane

    International Nuclear Information System (INIS)

    El-Hazek, N.T.; El Sayed, M.S.

    2003-01-01

    A new liquid emulsion membrane (LEM) process for uranium extraction from either dihydrate 28-30% P 2 O 5 (DH) or hemi-dihydrate 42-45% P 2 O 5 (HDH) wet process phosphoric acid is proposed. In this process, the organic component of the LEM is composed of a synergistic mixture of 0.1M di-2-ethyl hexyl phosphoric acid (DEHPA) and 0.025M trioctyl phosphine oxide (TOPO) with 4% Span 80. The internal or the strip acid phase is composed of 0.5M citric acid. The prepared LEM was proved to be stable in 42-45% P 2 O 5 acid concentration range and can, therefore, be applied to the phosphoric acid produced by the hemi-dihydrate process. After breakdown of the loaded emulsion, the uranyl citrate in the internal strip phase is separated by adding methanol followed by its calcination to the orange oxide. Most of the reagents used are recycled. The proposed process is characterized by simplicity, practically closed operation cycle in addition to lower capital and operating costs. (author)

  7. Physical properties of emulsion systems with SiO2 nanoparticles

    Directory of Open Access Journals (Sweden)

    Sergeev Vitaly Vyacheslavovich

    2017-11-01

    Full Text Available One of the most relevant directions for research and development (R&D in the area of oil and gas fields development is to study physicochemical impact onto petroleum reservoir to enhance development rate and increase oil recovery factor. Wide range of fields where nanoscale particles can be applied within this direction shifted the level of physicochemical processes studies from microscale to nanoscale, that caused significant advancement of the oil and gas industry as a whole. As for physicochemical methods for petroleum reservoir stimulation, the rapid development of nanotechnologies considerably improves understanding of the processes that run at the boundaries of phases liquid-liquid, liquid-gas, liquid-rock phases, etc. The most studied processes are the processes of influence of nanoscale particles on the interface between liquid-gas and liquid-liquid phases [1–18]. At the moment it is known that nanoparticles of various minerals and metals can increase lifetime of gas bubbles in hydrocarbon media and the stability of globules in hydrocarbon or aqueous phase in various types of emulsions [1–7, 12]. But in the industry there is no single understanding and explanation of physicochemical processes occurring at the boundaries of phases in the presence of nanoparticles under reservoir conditions or even in bench tests on rock cores. In this connection, the direction of nanoscale particles application in the oil and gas fields development is promising for carrying out complex R&D in order to reveal new scientific information and introduce high-performance inventions into the industry. The article presents the results of the next stage in complex research of silicon dioxide nanoparticles (SiO2 impact onto rheological and stability properties of emulsion systems. The complex research is performed within the framework of international project «Development and implementation of water-blocking agents based on application of SiO2 nanoparticles

  8. Water-in-oil emulsions prepared by peptide-silicone hybrid polymers as active interfacial modifier: effects of silicone oil species on dispersion stability of emulsions.

    Science.gov (United States)

    Sakai, Kenichi; Iijima, Satoshi; Ikeda, Ryosuke; Endo, Takeshi; Yamazaki, Takahiro; Yamashita, Yuji; Natsuisaka, Makoto; Sakai, Hideki; Abe, Masahiko; Sakamoto, Kazutami

    2013-01-01

    We have recently proposed a new general concept regarding amphiphilic materials that have been named as "active interfacial modifier (AIM)." In emulsion systems, an AIM is essentially insoluble in both water and organic solvents; however, it possesses moieties that are attracted to each of these immiscible liquid phases. Hence, an AIM practically stays just at the interface between the two phases and makes the resulting emulsion stable. In this study, the effects of silicone oil species on the dispersion stability of water-in-oil (W/O) emulsions in the presence of an AIM sample were evaluated in order to understand the destabilization mechanism in such emulsion systems. The AIM sample used in this study is an amphiphilic polymer consisting of a silicone backbone modified with hydrocarbon chains and hydrolyzed silk peptides. The Stokes equation predicts that the sedimentation velocity of water droplets dispersed in a continuous silicone oil phase simply depends on the expression (ρ - ρ₀)/η assuming that the droplet size is constant (where ρ is the density of the dispersed water phase, ρ₀ is the density of the continuous silicone oil phase, and η is the viscosity of the oil phase). The experimental results shown in this paper are consistent with the Stokes prediction: i.e., in the low-viscous genuine or quasi-Newtonian fluid region, the dispersion stability increases in the following order: dodecamethylpentasiloxane (DPS) D₅ > D₆. This indicates that our emulsion system experiences destabilization through sedimentation, but hardly any coalescence occurs owing to the presence of an additional third phase consisting of the AIM that stabilizes the silicone oil/water interface in the emulsions.

  9. International exchange of emergency phase information and assessments: an aid to inter/national decision makers

    International Nuclear Information System (INIS)

    Sullivan, T.J.

    2003-01-01

    Full text: Nuclear accidents/incidents cause significant fear in citizens perceived to be (potentially) impacted. Such events challenge national governments and international agencies to quickly and confidently provide assurance and protection advice. Based on the experience of several radiological accidents, e.g., Three Mile Island, Chernobyl, Algeciras, etc., it is evident that large areas, frequently transboundary, and numbers of citizens have the potential to be impacted. Additionally, as a consequence of current 'globalization', i.e. governmental, business, education and leisure travel, most nations now daily host numerous international visitors whose national government embassies have a responsibility to advise and project them from hazards. This mixture of large area, transboundary and international mobility presents a significant challenge to the decision maker community in order to deliver the best consistent advice to all those potentially impacted by a nuclear accident (and assure those not impacted). Post-Chernobyl there has been definitive progress and agreement in the determination of dose protection thresholds. In the same time period there has been a proliferation of dispersion models and assessment systems (from the local to the international scale) to support decision makers at all levels of government. Unfortunately, due to the varying parameters of scale, resolution, input data, and physics assumptions, the consequent assessment results can vary substantially enough [Atmes] to potentially cause confusion and even contradiction when presented to decision makers. Such a circumstance potentially leads to wrong decisions, undercuts confidence and negates all the work and benefits of good assessment calculations. From 1996 to 1999 Japan (JAERI) and the USA (LLNL) investigated, developed and tested an initial capability to share basic event information (start time, source/rates, local meteorology, local measurements, etc.) and calculated assessment

  10. Demulsification based on the thermal treatment (cooling and heating of W/O emulsions

    Directory of Open Access Journals (Sweden)

    Rajaković Vladana N.

    2004-01-01

    Full Text Available An important step in waste water treatment is the removal of oil from an O/W emulsion and the separation of oil and water into two phases, a process usually called demulsification. Modern methods of oil removal from waste water were described in the present study. Typical demulsification techniques include thermal, electrical, chemical, acoustic, or mechanical methods of emulsion treatment. The freeze/thaw process was found to be very effective for demulsification. In the freeze/thaw process, water removal from the W/O emulsion depends on the initial oil content, freezing temperature, freezing time, thawing rate and temperature. The described method is a non-destructive and physical method of emulsion treatment and because there is no addition of chemical agents there is no problem of further waste water treatment, which usually exists when chemicals are applied for demulsification. Different methods for oil content determination in the O/W emulsion were also applied and compared in this study (gravimetric, volumetric, measurement of oxygen consumption and emulsion pH, IR analysis of the emulsion, electro analytical measurement.

  11. A magnetic nanoparticle stabilized gas containing emulsion for multimodal imaging and triggered drug release.

    Science.gov (United States)

    Guo, Wei; Li, Diancheng; Zhu, Jia-an; Wei, Xiaohui; Men, Weiwei; Yin, Dazhi; Fan, Mingxia; Xu, Yuhong

    2014-06-01

    To develop a multimodal imaging guided and triggered drug delivery system based on a novel emulsion formulation composed of iron oxide nanoparticles, nanoscopic bubbles, and oil containing drugs. Iron oxide paramagnetic nanoparticles were synthesized and modified with surface conjugation of polyethylenimide (PEI) or Bovine Serum Albumin (BSA). Both particles were used to disperse and stabilize oil in water emulsions containing coumarin-6 as the model drug. Sulfur hexafluoride was introduced into the oil phase to form nanoscopic bubbles inside the emulsions. The resulted gas containing emulsions were evaluated for their magnetic resonance (MR) and ultrasound (US) imaging properties. The drug release profile triggered by ultrasound was also examined. We have successfully prepared the highly integrated multi-component emulsion system using the surface modified iron oxide nanoparticles to stabilize the interfaces. The resulted structure had distinctive MR and US imaging properties. Upon application of ultrasound waves, the gas containing emulsion would burst and encapsulated drug could be released. The integrated emulsion formulation was multifunctional with paramagnetic, sono-responsive and drug-carrying characteristics, which may have potential applications for disease diagnosis and imaging guided drug release.

  12. Effect of Nano-Scale Roughness on Particle Wetting and on Particle-Mediated Emulsion Stability

    Science.gov (United States)

    San Miguel, Adriana; Behrens, Sven

    2012-02-01

    Colloidal particles can strongly adsorb to liquid interfaces and stabilize emulsions against droplet coalescence, the effectiveness of which depends crucially on the particle wettability. From the study of macroscopic solids, surface wetting is known to be influenced strongly by nano-scale roughness (as seen e.g. in the ``Lotus effect'' or in anti-fog coatings); similarly, strong effects of particle roughness on particle-stabilized emulsions should be expected. Here we report the first experimental study of particle wetting and particle-mediated emulsion stability in which particle roughness could be varied continuously without varying the surface chemistry. We demonstrate an enabling method for preparing particles and macroscopic substrates with tunable nano-roughness and correlate the extent of roughness quantitatively with surface wetting (measured via the three-phase contact angle) and with emulsion stability (quantifiable via the maximum capillary pressure). Our results confirm a dramatic influence of roughness on wetting, emulsion stability, and even the type of emulsion formed (o/w vs. w/o) upon mixing oil with an aqueous particle dispersion. Whether particle roughness benefits emulsion stability or not is seen to depend on both the size and shape of the surface features.

  13. Effect of hydrate formation-dissociation on emulsion stability using DSC and visual techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lachance, J.W.; Dendy Sloan, E.; Koh, C.A. [Colorado School of Mines, Golden, CO (United States). Center for Hydrates Research

    2008-07-01

    Many flow assurance operators are now focusing on preventing hydrates from agglomerating and forming plugs within pipelines. A key factor in reducing plug formation in oil-dominated systems is the stability of emulsified water in gas hydrate formation. In this study, differential scanning calorimetry (DSC) studies were used to show that gas hydrate formation has a destabilizing effect on water and oil emulsions, and can result in a free water phase through the coalescence and agglomeration of dissociated hydrate particles. The study focused on investigating the ability of the hydrates to stay segregated with hydrate formation. The stability of water-in-oil emulsions with hydrate formation was investigated with a range of different crude oils with varying emulsion stability levels. Thermal properties were measured at both atmospheric and pressurized conditions. Thermocouples in the calorimetric furnace were used to measure the temperature difference between reference and sample cells. Emulsion stability was measured over a 1-month time period. Results of the study showed that hydrate formation and dissociation destabilizes emulsions. However, the asphaltene fraction in crude oils resists hydrate-induced destabilization. The stability of the emulsion increased when asphaltene content increased. It was concluded that emulsion stability is a key factor in preventing agglomeration in flow lines. 14 refs., 3 tabs., 8 figs.

  14. The structure of omega3 food emulsions

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Loussert, C.; Horn, Anna Frisenfeldt

    Fish oil is rich in polyunsaturated omega-3 fatty acids (omega-3 PUFAs) which are generally recognized as being beneficial to the health [1]. The addition of fish oil to food products is attractive to both the consumers and the food industry. Indeed, these components will improve nutritional value...... and add product value. Omega-3 PUFAs are rich in double bonds in their fatty acid chains and this attribute renders them highly susceptible to lipid oxidation. Omega-3 PUFAs can be added to food products as neat oil or as a delivery system such as oil-in-water emulsions. In this last configuration......, the oil is surrounded by an emulsifier e.g. proteins, phospholipids or hydro-colloids. This emulsifier layer is important and may protect the oil inside the droplets against prooxidants in the surrounding water phase; the emulsifier should act as a physical barrier between the omega-3 PUFAs...

  15. Heat Transfer in Boiling Dilute Emulsion with Strong Buoyancy

    Science.gov (United States)

    Freeburg, Eric Thomas

    Little attention has been given to the boiling of emulsions compared to that of boiling in pure liquids. The advantages of using emulsions as a heat transfer agent were first discovered in the 1970s and several interesting features have since been studied by few researchers. Early research focuses primarily on pool and flow boiling and looks to determine a mechanism by which the boiling process occurs. This thesis looks at the boiling of dilute emulsions in fluids with strong buoyant forces. The boiling of dilute emulsions presents many favorable characteristics that make it an ideal agent for heat transfer. High heat flux electronics, such as those seen in avionics equipment, produce high heat fluxes of 100 W/cm2 or more, but must be maintained at low temperatures. So far, research on single phase convection and flow boiling in small diameter channels have yet to provide an adequate solution. Emulsions allow the engineer to tailor the solution to the specific problem. The fluid can be customized to retain the high thermal conductivity and specific heat capacity of the continuous phase while enhancing the heat transfer coefficient through boiling of the dispersed phase component. Heat transfer experiments were carried out with FC-72 in water emulsions. FC-72 has a saturation temperature of 56 °C, far below that of water. The parameters were varied as follows: 0% ≤ epsilon ≤ 1% and 1.82 x 1012 ≤ RaH ≤ 4.42 x 1012. Surface temperatures along the heated surface reached temperature that were 20 °C in excess of the dispersed phase saturation temperature. An increase of ˜20% was seen in the average Nusselt numbers at the highest Rayleigh numbers. Holography was used to obtain images of individual and multiple FC-72 droplets in the boundary layer next to the heated surface. The droplet diameters ranged from 0.5 mm to 1.3 mm. The Magnus effect was observed when larger individual droplets were injected into the boundary layer, causing the droplets to be pushed

  16. Betting on Interferometric Paths and Phases Using Translational-Internal Entanglement:. the Greedy King Game

    Science.gov (United States)

    Kolář, Michal; Opatrný, Tomáš; Bar-Gill, Nir; Kurizki, Gershon

    The behavior of translationally-internally entangled (TIE) states in an interferometer of the Mach-Zehnder type is studied, by means of a game whose results show that TIE states allow near-certain guessing of both path (corpuscular) and phase (wavelike) features, as opposed to conventional states that are constrained by standard complementarity.

  17. The stability of emulsions

    NARCIS (Netherlands)

    Woods, Donald R.

    Recent work on the film thinning behavior during the coalescence of oil drops in water is summarized. In the experimental work, color movies were taken of the light interference patterns produced by the thin film of water trapped between the rising drop and the bulk oil phase. The drops were

  18. Acquisition of Co metal from spent lithium-ion battery using emulsion liquid membrane technology and emulsion stability test

    Science.gov (United States)

    Yuliusman; Wulandari, P. T.; Amiliana, R. A.; Huda, M.; Kusumadewi, F. A.

    2018-03-01

    Lithium-ion batteries are the most common type to be used as energy source in mobile phone. The amount of lithium-ion battery wastes is approximated by 200 – 500 ton/year. In one lithium-ion battery, there are 5 – 20% of cobalt metal, depend on the manufacturer. One of the way to recover a valuable metal from waste is leaching process then continued with extraction, which is the aim of this study. Spent lithium-ion batteries will be characterized with EDX and AAS, the result will show the amount of cobalt metal with form of LiCoO2 in the cathode. Hydrochloric acid concentration used is 4 M, temperature 80°C, and reaction time 1 hour. This study will discuss the emulsion stability test on emulsion liquid membrane. The purpose of emulsion stability test in this study was to determine optimum concentration of surfactant and extractant to produce a stable emulsion. Surfactant and extractant used were SPAN 80 and Cyanex 272 respectively with both concentrations varied. Membrane and feed phase ratios used in this experiment was 1 : 2. The optimum results of this study were SPAN 80 concentrations of 10% w/v and Cyanex 272 0.7 M.

  19. Interfacial film stabilized W/O/W nano multiple emulsions loaded with green tea and lotus extracts: systematic characterization of physicochemical properties and shelf-storage stability.

    Science.gov (United States)

    Mahmood, Tariq; Akhtar, Naveed; Manickam, Sivakumar

    2014-05-12

    Multiple emulsions have excellent encapsulating potential and this investigation has been aimed to encapsulate two different plant extracts as functional cosmetic agents in the W/O/W multiple emulsions and the resultant system's long term stability has been determined in the presence of a thickener, hydroxypropyl methylcellulose (HPMC). Multiple W/O/W emulsions have been generated using cetyl dimethicone copolyol as lipophilic emulsifier and a blend of polyoxyethylene (20) cetyl ether and cetomacrogol 1000® as hydrophilic emulsifiers. The generated multiple emulsions have been characterized with conductivity, pH, microscopic analysis, phase separation and rheology for a period of 30 days. Moreover, long term shelf-storage stability has been tested to understand the shelf-life by keeping the generated multiple emulsion formulations at 25 ± 10°C and at 40 ± 10% relative humidity for a period of 12 months. It has been observed that the hydrophilic emulsifiers and HPMC have considerably improved the stability of multiple emulsions for the followed period of 12 months at different storage conditions. These multiple emulsions have shown improved entrapment efficiencies concluded on the release rate of conductometric tracer entrapped in the inner aqueous phase of the multiple emulsions. Multiple emulsions have been found to be stable for a longer period of time with promising characteristics. Hence, stable multiple emulsions loaded with green tea and lotus extracts could be explored for their cosmetic benefits.

  20. Steroidal Compounds in Commercial Parenteral Lipid Emulsions

    Directory of Open Access Journals (Sweden)

    Rafat A. Siddiqui

    2012-08-01

    Full Text Available Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn® II, Liposyn® III, Lipofundin® MCT, Lipofundin® N, Structolipid®, Intralipid®, Ivelip® and ClinOleic®. Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction.

  1. Steroidal Compounds in Commercial Parenteral Lipid Emulsions

    Science.gov (United States)

    Xu, Zhidong; Harvey, Kevin A.; Pavlina, Thomas; Dutot, Guy; Hise, Mary; Zaloga, Gary P.; Siddiqui, Rafat A.

    2012-01-01

    Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn® II, Liposyn® III, Lipofundin® MCT, Lipofundin® N, Structolipid®, Intralipid®, Ivelip® and ClinOleic®. Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction. PMID:23016123

  2. Pickering emulsion stabilized by cashew gum- poly-l-lactide copolymer nanoparticles: Synthesis, characterization and amphotericin B encapsulation.

    Science.gov (United States)

    Richter, A R; Feitosa, J P A; Paula, H C B; Goycoolea, F M; de Paula, R C M

    2018-04-01

    In this work, we provide proof-of-concept of formation, physical characteristics and potential use as a drug delivery formulation of Pickering emulsions (PE) obtained by a novel method that combines nanoprecipitation with subsequent spontaneous emulsification process. To this end, pre-formed ultra-small (d.∼10 nm) nanoprecipitated nanoparticles of hydrophobic derivatives of cashew tree gum grafted with polylactide (CGPLAP), were conceived to stabilize Pickering emulsions obtained by spontaneous emulsification. These were also loaded with Amphotericin B (AmB), a drug of low oral bioavailability used in the therapy of neglected diseases such as leishmaniasis. The graft reaction was performed in two CG/PLA molar ratio conditions (1:1 and 1:10). Emulsions were prepared by adding the organic phase (Miglyol 812 ® ) in the aqueous phase (nanoprecipitated CGPLAP), resulting the immediate emulsion formation. The isolation by centrifugation does not destabilize or separate the nanoparticles from oil droplets of the PE emulsion. Emulsions with CGPLAP 1:1 presented unimodal distributions at different CGPLA concentration, lower values in size and PDI and the best stability over time. The AmB was incorporated in the emulsions with a process efficiency of 21-47%, as determined by UV-vis. AmB in CGPLAP emulsions is in less aggregated state than observed in commercial AmB formulation. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Influence of maltodextrin dextrose equivalent value on rheological and dispersion properties of sunflower oil in water emulsions

    Directory of Open Access Journals (Sweden)

    Dokić Petar P.

    2004-01-01

    Full Text Available Effect of dextrose equivalent (DE of maltodextrin present in continuous phase on flow along with dispersion properties of sunflower oil in water emulsions has been investigated. Both, rheological and disperse characteristics of the emulsions were greatly influenced by continuous phase viscosity and thus by the DE value of maltodextrin.. The smaller DE value the greater high shear viscosity and the smaller the droplet size. Irrespective of the amount and DE value of maltodextrin used was, all the emulsions showed a pseudoplastic behaviour.

  4. Effect of fat type and heat treatment on the microstructure of meat emulsions

    DEFF Research Database (Denmark)

    Miklos, Rikke; Lametsch, René; Nielsen, Mikkel Schou

    2013-01-01

    in microstructure of meat emulsions by use of a novel quantitative application of absorption- and phase-contrast tomography. The non-invasive technique offered the possibility to study the same sample in both raw and cooked condition. The samples were raw and heat treated meat emulsions (10% protein, 25% fat, 60......% moisture) prepared with either pork fat or sunflower oil. The tomograms were obtained at a synchrotron facility using a grating interferometer which measured three different properties in the sample simultaneously: The attenuation length, the electron density and the diffusion length. Phase contrast...... of the added fat. Use of vegetable oil resulted in homogeneous emulsions with smaller fat globules compared to the use of pork fat. This has previously been shown by the use of light micrographs. However, with the use of phase contrast imaging it was, from the same image, possible to resolve the protein phase...

  5. Oxidation mechanisms in real food emulsions : Method for separation of mayonnaise by ultracentrifugation

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Meyer, Anne S.; Adler-Nissen, Jens

    1998-01-01

    With the aim of studying partition coefficients of antioxidants and secondary oxidation products in a real food emulsion a method,for the separation of mayonnaise was developed. The method included freezing and a mild precentrifugation step followed by ultracentrifugation at 197,500 x g. The prec......With the aim of studying partition coefficients of antioxidants and secondary oxidation products in a real food emulsion a method,for the separation of mayonnaise was developed. The method included freezing and a mild precentrifugation step followed by ultracentrifugation at 197,500 x g....... The precentrifugation separated most of the oil (96%) from the rest of the mayonnaise. The ultracentrifugation separated the remaining fraction into four phases: a small oil phase constituting 0.25% of the total, a relatively small emulsion phase (approximately 5% w/w), an almost translucent aqueous phase...

  6. Investigation the physicochemical properties and stability of w/o emulsion

    International Nuclear Information System (INIS)

    Iqbal, S.; Baloch, M.K.; Hameed, G.

    2014-01-01

    The study aims to investigate the stability of W/O emulsions with respect to coalescence time. The various concentrations of water were dispersed in oil phase (soybean oil). The compositions of organic and aqueous phases were varied by adding emulsifier (Monoglyceride), sodium chloride and thickening agent (mango's pulp). The technique employed for the mixing of two phases was homogenization. The Emulsion Stability Index (ESI), Viscosity changes, separation of organic and aqueous phases as a function of storage time have been studied. It has been found that monoglyceride increases the stability and decreases the emulsion stability index (ESI) and also decreases the viscosity changes with storage time while electrolytes and mango's pulp encourage the coalescence process and enhance the instability of the system. On the other hand the system that contained all the organic and aqueous ingredients showed high stability. (author)

  7. Emulsion-Based Intradermal Delivery of Melittin in Rats.

    Science.gov (United States)

    Han, Sang Mi; Kim, Se Gun; Pak, Sok Cheon

    2017-05-19

    Bee venom (BV) has long been used as a traditional medicine. The aim of the present study was to formulate a BV emulsion with good rheological properties for dermal application and investigate the effect of formulation on the permeation of melittin through dermatomed rat skin. A formulated emulsion containing 1% ( w / v ) BV was prepared. The emulsion was compared with distilled water (DW) and 25% ( w / v ) N -methyl-2-pyrrolidone (NMP) in DW. Permeation of melittin from aqueous solution through the dermatomed murine skin was evaluated using the Franz diffusion cells. Samples of receptor cells withdrawn at pre-determined time intervals were measured for melittin amount. After the permeation study, the same skin was used for melittin extraction. In addition, a known amount of melittin (5 μg/mL) was added to stratum corneum, epidermis, and dermis of the rat skin, and the amount of melittin was measured at pre-determined time points. The measurement of melittin from all samples was done with HPLC-MS/MS. No melittin was detected in the receptor phase at all time points in emulsion, DW, or NMP groups. When the amount of melittin was further analyzed in stratum corneum, epidermis, and dermis from the permeation study, melittin was still not detected. In an additional experiment, the amount of melittin added to all skin matrices was corrected against the amount of melittin recovered. While the total amount of melittin was retained in the stratum corneum, less than 10% of melittin remained in epidermis and dermis within 15 and 30 min, respectively. Skin microporation with BV emulsion facilitates the penetration of melittin across the stratum corneum into epidermis and dermis, where emulsified melittin could have been metabolized by locally-occurring enzymes.

  8. Emulsion-Based Intradermal Delivery of Melittin in Rats

    Directory of Open Access Journals (Sweden)

    Sang Mi Han

    2017-05-01

    Full Text Available Bee venom (BV has long been used as a traditional medicine. The aim of the present study was to formulate a BV emulsion with good rheological properties for dermal application and investigate the effect of formulation on the permeation of melittin through dermatomed rat skin. A formulated emulsion containing 1% (w/v BV was prepared. The emulsion was compared with distilled water (DW and 25% (w/v N-methyl-2-pyrrolidone (NMP in DW. Permeation of melittin from aqueous solution through the dermatomed murine skin was evaluated using the Franz diffusion cells. Samples of receptor cells withdrawn at pre-determined time intervals were measured for melittin amount. After the permeation study, the same skin was used for melittin extraction. In addition, a known amount of melittin (5 μg/mL was added to stratum corneum, epidermis, and dermis of the rat skin, and the amount of melittin was measured at pre-determined time points. The measurement of melittin from all samples was done with HPLC-MS/MS. No melittin was detected in the receptor phase at all time points in emulsion, DW, or NMP groups. When the amount of melittin was further analyzed in stratum corneum, epidermis, and dermis from the permeation study, melittin was still not detected. In an additional experiment, the amount of melittin added to all skin matrices was corrected against the amount of melittin recovered. While the total amount of melittin was retained in the stratum corneum, less than 10% of melittin remained in epidermis and dermis within 15 and 30 min, respectively. Skin microporation with BV emulsion facilitates the penetration of melittin across the stratum corneum into epidermis and dermis, where emulsified melittin could have been metabolized by locally-occurring enzymes.

  9. Effect of lipophilization of dihydrocaffeic acid on its antioxidative properties in fish oil enriched emulsion

    DEFF Research Database (Denmark)

    Sørensen, Ann-Dorit Moltke; de Diego, Sara; Petersen, Lone Kristine

    oxidation than PUFAs from vegetable oils due to their highly polyunsaturated nature, it is necessary to develop methods to protect these PUFAs. Many food systems are emulsions. Due to the so-called polar paradox phenomenon, hydrophilic antioxidants may in many cases be better antioxidants in bulk oil than...... lipophilic compounds, whereas lipophilic antioxidants are more efficient than hydrophilic antioxidants in emulsions. This phenomenon has been explained by the affinity of the compounds towards the different phases in bulk oil and emulsions. The hydrophilic character of many naturally occurring antioxidants...... that generally, lipophilized dihydrocaffeic acid and rutin increased the oxidative stability of o/w emulsions and fish oil enriched milk compared with their parent compound. The results supported a cut-off effect in relation to the acyl chain length esterified to the phenolic compound. Octyl dihydrocaffeate (C8...

  10. Antioxidant Efficacies of Rutin and Rutin Esters in Bulk Oil and Oil-in-Water Emulsion

    DEFF Research Database (Denmark)

    Lue, Bena-Marie; Sørensen, Ann-Dorit Moltke; Jacobsen, Charlotte

    2017-01-01

    The use of flavonoids as antioxidants in food formulations is limited due to their solubility and thereby their localization in the food products. However, enzymatic alkylation of flavonoids with lipophilic moieties alters their lipophilicity and thereby partitioning within different phases...... concentrations (25 and 200 µM) was assessed in bulk oil and in an o/w emulsion system without and with iron addition. All evaluated compounds revealed antioxidant effects. However, rutin and BHT were the most efficient antioxidants in bulk oil followed by rutin palmitate, whereas rutin laurate acted as either...... in o/w emulsion. Interestingly, rutin had stronger antioxidative effect than BHT upon iron addition to the emulsion. Practical application: According to the antioxidant hypothesis the polar paradox more amphiphilic antioxidants should perform as better antioxidants in emulsions than more polar...

  11. Stability of large diameter W1/O/W2 emulsion particles

    International Nuclear Information System (INIS)

    Wang Guoxiu; Su Lin; Chen Sufen; Li Bo; Yao Hong; Deng Yi; Wei Jianjun

    2012-01-01

    W 1 /O/W 2 double emulsion particles of around 2 mm diameter were prepared using emulsion microencapsulation method. The stability of the particles was studied under the quasi-static condition and the rotating flow field, respectively, with the variation of the organic phase concentration and the water-soluble polymer concentration. The enhancement mechanism of the kinetic stability of the particles was explored based on force analysis and deformation analysis. The results show that, both under the quasi-static condition and the rotating flow field, the stability of W 1 /O/W 2 double emulsion particles increases with the in- crease of PS concentration. However, it increases firstly and then decreases when PVA concentration increases. Moreover, in some conditions, the kinetic stability of W 1 /O/W 2 double emulsion particles is greatly enhanced in the rotating flow field com- pared with under the quasi-static condition. (authors)

  12. Emulsions of crude glycerin from biodiesel processing with fuel oil for industrial heating.

    Science.gov (United States)

    Mize, Hannah E; Lucio, Anthony J; Fhaner, Cassie J; Pratama, Fredy S; Robbins, Lanny A; Karpovich, David S

    2013-02-13

    There is considerable interest in using crude glycerin from biodiesel production as a heating fuel. In this work crude glycerin was emulsified into fuel oil to address difficulties with ignition and sustained combustion. Emulsions were prepared with several grades of glycerin and two grades of fuel oil using direct and phase inversion emulsification. Our findings reveal unique surfactant requirements for emulsifying glycerin into oil; these depend on the levels of several contaminants, including water, ash, and components in MONG (matter organic non-glycerin). A higher hydrophile-lipophile balance was required for a stable emulsion of crude glycerin in fuel oil compared to water in fuel oil. The high concentration of salts from biodiesel catalysts generally hindered emulsion stability. Geometric close-packing of micelles was carefully balanced to mechanically stabilize emulsions while also enabling low viscosity for pumping and fuel injection. Phase inversion emulsification produced more stable emulsions than direct emulsification. Emulsions were tested successfully as fuel for a waste oil burner.

  13. Pickering emulsions for skin decontamination.

    Science.gov (United States)

    Salerno, Alicia; Bolzinger, Marie-Alexandrine; Rolland, Pauline; Chevalier, Yves; Josse, Denis; Briançon, Stéphanie

    2016-08-01

    This study aimed at developing innovative systems for skin decontamination. Pickering emulsions, i.e. solid-stabilized emulsions, containing silica (S-PE) or Fuller's earth (FE-PE) were formulated. Their efficiency for skin decontamination was evaluated, in vitro, 45min after an exposure to VX, one of the most highly toxic chemical warfare agents. Pickering emulsions were compared to FE (FE-W) and silica (S-W) aqueous suspensions. PE containing an oil with a similar hydrophobicity to VX should promote its extraction. All the formulations reduced significantly the amount of VX quantified on and into the skin compared to the control. Wiping the skin surface with a pad already allowed removing more than half of VX. FE-W was the less efficient (85% of VX removed). The other formulations (FE-PE, S-PE and S-W) resulted in more than 90% of the quantity of VX removed. The charge of particles was the most influential factor. The low pH of formulations containing silica favored electrostatic interactions of VX with particles explaining the better elimination from the skin surface. Formulations containing FE had basic pH, and weak interactions with VX did not improve the skin decontamination. However, these low interactions between VX and FE promote the transfer of VX into the oil droplets in the FE-PE. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Evolution of equilibrium Pickering emulsions--a matter of time scales.

    Science.gov (United States)

    Kraft, Daniela J; Luigjes, Bob; de Folter, Julius W J; Philipse, Albert P; Kegel, Willem K

    2010-09-30

    A new class of equilibrium solid-stabilized oil-in-water emulsions harbors a competition of two processes on disparate time scales that affect the equilibrium droplet size in opposing ways. The aim of this work is to elucidate the molecular origins of these two time scales and demonstrate their effects on the evolution of the emulsion droplet size. First, spontaneous emulsification into particle-covered droplets occurs through in situ generation of surface-active molecules by hydrolysis of molecules of the oil phase. We show that surface tensions of the oil-water interfaces in the absence of stabilizing colloidal particles are connected to the concentration of these surface-active molecules, and hence also to the equilibrium droplet size in the presence of colloids. As a consequence, the hydrolysis process sets the time scale of formation of these solid-stabilized emulsions. A second time scale is governing the ultimate fate of the solid-stabilized equilibrium emulsions: by condensation of the in situ generated amphiphilic molecules onto the colloidal particles, their wetting properties change, leading to a gradual transfer from the aqueous to the oil phase via growth of the emulsion droplets. This migration is observed macroscopically by a color change of the water and oil phases, as well as by electron microscopy after polymerization of the oil phase in a phase separated sample. Surprisingly, the relative oil volume sets the time scale of particle transfer. Phase separation into an aqueous phase and an oil phase containing colloidal particles is influenced by sedimentation of the emulsion droplets. The two processes of formation of surface-active molecules through hydrolysis and condensation thereof on the colloidal surface have an opposite influence on the droplet size. By their interplay, a dynamic equilibrium is created where the droplet size always adjusts to the thermodynamically stable state.

  15. Microcellular open porous monoliths for cell growth by thiol-ene polymerization of low-toxicity monomers in high internal phase emulsions

    Czech Academy of Sciences Publication Activity Database

    Sušec, M.; Liska, R.; Russmüller, G.; Kotek, Jiří; Krajnc, P.

    2015-01-01

    Roč. 15, č. 2 (2015), s. 253-261 ISSN 1616-5187 Institutional support: RVO:61389013 Keywords : divinyl adipate * polyHIPE * porous polymers Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.680, year: 2015

  16. The potential applications in heavy oil EOR with the nanoparticle and surfactant stabilized solvent-based emulsion

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, F. [Texas A and M Univ., College Station, TX (United States)

    2010-07-01

    The main challenges in developing the heavy oil reservoirs in the Alaska North Slope (ANS) include technical challenges regarding thermal recovery; sand control and disposal; high asphaltene content; and low in-situ permeability. A chemical enhanced oil recovery method may be possible for these reservoirs. Solvent based emulsion flooding provides mobility control; oil viscosity reduction; and in-situ emulsification of heavy oil. This study evaluated the potential application of nano-particle-stabilized solvent based emulsion injection to enhance heavy oil recovery in the ANS. The optimized micro-emulsion composition was determined using laboratory tests such as phase behaviour scanning, rheology studies and interfacial tension measurements. The optimized nano-emulsions were used in core flooding experiments to verify the recovery efficiency. The study revealed that the potential use of this kind of emulsion flooding is a promising enhanced oil recovery process for some heavy oil reservoirs in Alaska, Canada and Venezuela. 4 refs., 2 tabs., 10 figs.

  17. Response of nuclear emulsions to ionizing radiations

    International Nuclear Information System (INIS)

    Katz, R.; Pinkerton, F.E.

    1975-01-01

    Heavy ion tracks in Ilford K-2 emulsion are simulated with a computer program which makes use of the delta-ray theory of track structure, and the special assumption that the response of this emulsion to gamma-rays is 8-or-more hit. The Ilford K-series of nuclear emulsions is produced from a parent stock called K.0 emulsion, sensitized to become K.1 to K.5, and desensitized to become K-1 to K-3. Our simulations demonstrate that the emulsions K.5 through K.0 to K-1 are 1-or-more hit detectors, while K-2 is an 8-or-more hit detector. We have no data for K-3 emulsion. It would appear that emulsions of intermediate hittedness might be produced by an intermediate desensitization, to mimic or match the RBE-LET variations of biological cells, perhaps to produce a ''rem-dosimeter''. In the K-2 emulsion no developable gains are produced by stopping H, He, and Li ions. The emulsion has ''threshold-like'' properties, resembling etchable track detectors. It should prove useful in the measurement of high LET dose in a strong low LET background, as for pions or neutrons. Since it can be expected to accumulate and repair ''sub-lethal damage'', to display the ion-kill and gamma-kill inactivation modes, the grain-count and track width regimes, it may serve to model biological effects. (auth)

  18. Radiation induced emulsion polymerization of vinylidene chloride

    International Nuclear Information System (INIS)

    Panajkar, M.S.; Rao, K.N.

    1979-01-01

    Gamma ray induced emulsion polymerization of vinylidene chloride has been carried out and the percent conversion of monomer to polymer and molecular weights of emulsion polymer were measured as a function of time and emulsifier concentration. Rp was found to be dependent on 0.3 power of emulsifier concentration whereas molecular weights increased with conversion and emulsifier concentration. The number of particles N also increased with conversion contrary to Smith Ewart's theory of emulsion polymerization. The results are discussed in the light of existing theories of emulsion polymerization. (author)

  19. Internal stresses and stability of the tetragonal phase in zirconia thin layers deposited by OMCVD

    Science.gov (United States)

    Benali, B.; Huntz, A. M.; Andrieux, M.; Ignat, M.; Poissonnet, S.

    2008-07-01

    Zirconia thin films were deposited by OMCVD (organo-metallic chemical vapour deposition) at various temperatures and oxygen partial pressures on a AISI 301 stainless steel substrate with Zr(thd) 4 as precursor. The as deposited 250 nm thin zirconia films presented a structure consisting of two phases: the expected monoclinic one and also an unexpected tetragonal phase. According to the literature, the stabilization of the tetragonal phase (metastable in massive zirconia) can be related to the crystallite size and/or to the generated internal compressive stresses. To analyze the effect of internal and external stresses on the thin film behaviour, in-situ tensile experiments were performed at room temperature and at high temperature (500 °C). Depending on the process parameters, phase transformations and damage evolution of the films were observed. Our results, associated to XRD (X-ray diffraction) analyses, used to determine phase ratios and residual stresses within the films, before and after the mechanical experiments, are discussed with respect to their microstructural changes.

  20. The stability of water-in-crude and model oil emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, A.P.; Zaki, N.N.; Kilpatrick, P.K. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Chemical Engineering; Sjoblom, J. [Norwegian Univ. of Science and Technology, Trondheim (Norway). Dept. of Chemical Engineering, Ugelstad Laboratory

    2007-12-15

    Emulsions are among the most persistent problems faced by petroleum producers. Water is added at refineries to generate a large oil-water interfacial area to facilitate the extraction of salts from the crude oil. The produced emulsions do not readily resolve into neat crude and water phases, and some volume of the emulsion remains. This paper described the surface-active components in petroleum as well as methods of measuring emulsion stability. The stabilities of a variety of water-in-model oil and petroleum emulsions were measured using the critical electric field (CEF) technique. In this study, CEF was used to measure the stability of water-in-heptane-toluene-asphaltene emulsions. Results for emulsions with 60 and 30 per cent water were presented. The effect of interfacial film thickness was discussed and a kinetic model for interfacial film formation was presented. The importance of solvation of asphaltenes to emulsion stability was confirmed along with the importance of the state of asphaltene aggregation. It was shown that emulsion stability increased with the concentration of soluble asphaltenes near the point of precipitation. In order to calculate interfacial area and film thickness, optical microscopy was used to measure droplet size. Film thickness increased with asphaltene concentration up to the solubility limit. Increased concentration above that limit had little effect. CEF increased with interfacial film thickness up to a monolayer coverage of asphaltene aggregates, but film thickness had a much smaller effect above the monolayer. These results were used to develop correlations of the stability of water-in-crude oil emulsions. A strong correlation was found for CEF with the product of asphaltene concentration and the difference in hydrogen to carbon atomic ratios of the asphaltenes and petroleum solvent. The effects of asphaltene chemistry, solvency, and resin concentration on the adsorption and consolidation of emulsion stabilizing interfacial

  1. Natural Oil-Based Emulsion Containing Allantoin Versus Aqueous Cream for Managing Radiation-Induced Skin Reactions in Patients With Cancer: A Phase 3, Double-Blind, Randomized, Controlled Trial

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Raymond Javan, E-mail: email.rchan@gmail.com [Cancer Care Services, Royal Brisbane and Women' s Hospital, Herston, Queensland (Australia); School of Nursing, Queensland University of Technology, Kelvin Grove (Australia); Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove (Australia); Mann, Jennifer; Tripcony, Lee; Keller, Jacqui; Cheuk, Robyn; Blades, Rae [Cancer Care Services, Royal Brisbane and Women' s Hospital, Herston, Queensland (Australia); Keogh, Samantha [National Health and Medical Research Council Centre for Research Excellence in Nursing, Centre for Health Practice Innovation–Griffith Health Institute, Griffith University, Nathan (Australia); Poole, Christopher [Cancer Care Services, Royal Brisbane and Women' s Hospital, Herston, Queensland (Australia); Science and Engineering Faculty, Queensland University of Technology, Brisbane (Australia); Walsh, Christopher [Cancer Care Services, Royal Brisbane and Women' s Hospital, Herston, Queensland (Australia)

    2014-11-15

    Purpose: To investigate the effects of a natural oil-based emulsion containing allantoin versus aqueous cream for preventing and managing radiation-induced skin reactions. Methods and Materials: A total of 174 patients were randomized and participated in the study. Patients received either cream 1 (the natural oil-based emulsion containing allantoin) or cream 2 (aqueous cream). Skin toxicity, pain, itching, and skin-related quality of life scores were collected for up to 4 weeks after radiation treatment. Results: Patients who received cream 1 had a significantly lower average level of Common Terminology Criteria for Adverse Events at week 3 (P<.05) but had statistically higher average levels of skin toxicity at weeks 7, 8, and 9 (all P<.001). Similar results were observed when skin toxicity was analyzed by grades. With regards to pain, patients in the cream 2 group had a significantly higher average level of worst pain (P<.05) and itching (P=.046) compared with the cream 1 group at week 3; however, these differences were not observed at other weeks. In addition, there was a strong trend for cream 2 to reduce the incidence of grade 2 or more skin toxicity in comparison with cream 1 (P=.056). Overall, more participants in the cream 1 group were required to use another topical treatment at weeks 8 (P=.049) and 9 (P=.01). Conclusion: The natural oil-based emulsion containing allantoin seems to have similar effects for managing skin toxicity compared with aqueous cream up to week 5; however, it becomes significantly less effective at later weeks into the radiation treatment and beyond treatment completion (week 6 and beyond). There were no major differences in pain, itching, and skin-related quality of life. In light of these results, clinicians and patients can base their decision on costs and preferences. Overall, aqueous cream seems to be a more preferred option.

  2. Natural Oil-Based Emulsion Containing Allantoin Versus Aqueous Cream for Managing Radiation-Induced Skin Reactions in Patients With Cancer: A Phase 3, Double-Blind, Randomized, Controlled Trial

    International Nuclear Information System (INIS)

    Chan, Raymond Javan; Mann, Jennifer; Tripcony, Lee; Keller, Jacqui; Cheuk, Robyn; Blades, Rae; Keogh, Samantha; Poole, Christopher; Walsh, Christopher

    2014-01-01

    Purpose: To investigate the effects of a natural oil-based emulsion containing allantoin versus aqueous cream for preventing and managing radiation-induced skin reactions. Methods and Materials: A total of 174 patients were randomized and participated in the study. Patients received either cream 1 (the natural oil-based emulsion containing allantoin) or cream 2 (aqueous cream). Skin toxicity, pain, itching, and skin-related quality of life scores were collected for up to 4 weeks after radiation treatment. Results: Patients who received cream 1 had a significantly lower average level of Common Terminology Criteria for Adverse Events at week 3 (P<.05) but had statistically higher average levels of skin toxicity at weeks 7, 8, and 9 (all P<.001). Similar results were observed when skin toxicity was analyzed by grades. With regards to pain, patients in the cream 2 group had a significantly higher average level of worst pain (P<.05) and itching (P=.046) compared with the cream 1 group at week 3; however, these differences were not observed at other weeks. In addition, there was a strong trend for cream 2 to reduce the incidence of grade 2 or more skin toxicity in comparison with cream 1 (P=.056). Overall, more participants in the cream 1 group were required to use another topical treatment at weeks 8 (P=.049) and 9 (P=.01). Conclusion: The natural oil-based emulsion containing allantoin seems to have similar effects for managing skin toxicity compared with aqueous cream up to week 5; however, it becomes significantly less effective at later weeks into the radiation treatment and beyond treatment completion (week 6 and beyond). There were no major differences in pain, itching, and skin-related quality of life. In light of these results, clinicians and patients can base their decision on costs and preferences. Overall, aqueous cream seems to be a more preferred option

  3. Emulsion Hydrogel Soft Motor Actuated by Thermal Stimulation.

    Science.gov (United States)

    Wang, Hui; Liang, Yuling; Gao, Wei; Dong, Renfeng; Wang, Chaoyang

    2017-12-13

    An emulsion hydrogel motor (E-H motor), constituted by low-boiling-point oil fuel and a hydrogel matrix, is prepared through a simple yet versatile oil-in-water (O/W) emulsion template method. The E-H motor can be efficiently propelled by the bubbles generated under a thermal stimulus. As thermally induced explosion occurs inside the E-H motor (diameter ∼4.0 mm and length ∼6.0 mm), the gas bubbles resulting from thermotropic phase transition are violently ejected from one side, leading to a fast speed of 14.78 ± 4.82 mm s -1 in a 60 °C aqueous solution. Additionally, multiple water-insoluble organic solvents can serve as the fuel for self-propulsion, which demonstrates the favorable universality of the E-H motor. The magnetic navigation and near-infrared propulsion can be realized through incorporating hydrophilic iron oxide (Fe 3 O 4 ) nanoparticles and graphene oxide (GO) into the aqueous phase. Moreover, the synchronous integration of GO and enrofloxacin bactericide can enable intelligent targeted cargo transportation and delivery. The attractive self-propulsion performance, precise locomotion control, and formidable integration ability of the emulsion hydrogel-based miniaturized soft motor hold great promise for numerous practical applications.

  4. Characterization and stability studies of emulsion systems containing pumice

    Directory of Open Access Journals (Sweden)

    Marilene Estanqueiro

    2014-04-01

    Full Text Available Emulsions are the most common form of skin care products. However, these systems may exhibit some instability. Therefore, when developing emulsions for topical application it is interesting to verify whether they have suitable physical and mechanical characteristics and further assess their stability. The aim of this work was to study the stability of emulsion systems, which varied in the proportion of the emulsifying agent cetearyl alcohol (and sodium lauryl sulfate (and sodium cetearyl sulfate (LSX, the nature of the oily phase (decyl oleate, cyclomethicone or dimethicone and the presence or absence of pumice (5% w/w. While maintaining the samples at room temperature, rheology studies, texture analysis and microscopic observation of formulations with and without pumice were performed. Samples were also submitted to an accelerated stability study by centrifugation and to a thermal stress test. Through the testing, it was found that the amount of emulsifying agent affects the consistency and textural properties such as firmness and adhesiveness. So, formulations containing LSX (5% w/w and decyl oleate or dimethicone as oily phase had a better consistency and remained stable with time, so exhibited the best features to be used for skin care products.

  5. Simple, reversible emulsion system switched by pH on the basis of chitosan without any hydrophobic modification.

    Science.gov (United States)

    Liu, Hao; Wang, Chaoyang; Zou, Shengwen; Wei, Zengjiang; Tong, Zhen

    2012-07-31

    Chitosan without hydrophobic modification is not a good emulsifier itself. However, it has a pH-tunable sol-gel transition due to free amino groups along its backbone. In the present work, a simple reversible Pickering emulsion system based on the pH-tunable sol-gel transition of chitosan was developed. At pH > 6.0, as adjusted by NaOH, chitosan was insoluble in water. Chitosan nanoparticles or micrometer-sized floccular precipitates were formed in situ. These chitosan aggregates could adsorb at the interface of oil and water to stabilize the o/w emulsions, so-called Pickering emulsions. At pH organic solvents (liquid paraffin, n-hexane, toluene, and dichloromethane) were chosen as the oil phase. Reversible emulsions were formed for all four oils. Chitosan-based Pickering emulsions could undergo five cycles of emulsification-demulsification with only a slight increase in the emulsion droplet size. They also had good long-term stability for more than 2 months. Herein, we give an example of chitosan without any hydrophobic modification to act as an effective emulsifier for various oil-water systems. From the results, we have determined that natural polymers with a stimulus-responsive sol-gel transition should be a good particulate emulsifier. The method for in situ formation of pH-responsive Pickering emulsions based on chitosan will open up a new route to the preparation of a wide range of reversible emulsions.

  6. Poly(isobutylene) nanoparticles via cationic polymerization in nonaqueous emulsions.

    Science.gov (United States)

    Schuster, Thomas; Golling, Florian E; Krumpfer, Joseph W; Wagner, Manfred; Graf, Robert; Alsaygh, Abdulhamid A; Klapper, Markus; Müllen, Klaus

    2015-01-01

    The preparation of poly(isobutylene) (PIB) nanoparticles via cationic emulsion polymerization is presented. As a requirement, an oil-in-perfluoroalkane nonaqueous emulsion is developed, which is inert under the carbocationic polymerization conditions. To stabilize the dichloromethane/hexane droplets in the fluorinated, continuous phase, an amphiphilic block copolymer emulsifier is prepared containing PIB and 1H,1H-perfluoroalkylated poly(pentafluorostyrene) blocks. This system allows for the polymerization of isobutylene with number-average molecular weights (Mn) up to 27,000 g mol(-1). The particle morphologies are characterized via dynamic light scattering and electron microscopy. For Mn > 20,000 g mol(-1), the particles exhibit shape-persistence at room temperature and are ≈100 nm in diameter. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. RIMS International Conference : Mathematical Challenges in a New Phase of Materials Science

    CERN Document Server

    Kotani, Motoko

    2016-01-01

    This volume comprises eight papers delivered at the RIMS International Conference "Mathematical Challenges in a New Phase of Materials Science", Kyoto, August 4–8, 2014. The contributions address subjects in defect dynamics, negatively curved carbon crystal, topological analysis of di-block copolymers, persistence modules, and fracture dynamics. These papers highlight the strong interaction between mathematics and materials science and also reflect the activity of WPI-AIMR at Tohoku University, in which collaborations between mathematicians and experimentalists are actively ongoing.

  8. Phase acceleration: a new important parameter in GPS occultation monitoring of the atmospheric internal waves

    Science.gov (United States)

    Pavelyev, A. G.; Liou, Y. A.; Wickert, J.; Schmidt, T.; Pavelev, A. A.; Gubenko, V. N.

    2009-04-01

    After forty years of radio occultation (RO) experiments it is clear now that the phase acceleration of radio waves has the same importance as the Doppler frequency. This was shown by use of analysis of high-stability GPS RO signals. Phase acceleration technique allows one to convert the phase and Doppler frequency changes to the refraction attenuation variations. From the derived refraction attenuation one can estimate the integral absorption of radio waves by use of the amplitude data. This is important for measurement of water vapor and minor atmospheric gas constituents in future RO missions because of excluding the difficulty with removing the refraction attenuation effect from the amplitude data. Phase acceleration/intensity technique can be applied to separate the influence of layered structures from contributions of irregularities and turbulence in the atmosphere and ionosphere. Phase acceleration/intensity technique can be applied also for location and determination of the height and inclination of the layered structures in the atmosphere and ionosphere. In many cases the layered structures in the atmosphere indicate quasi-periodical altitude dependence that reveals their wave origin. The altitude profile of the vertical gradient of refractivity of the layered structures can be used to find the main characteristics of the internal wave activity with a global coverage. In general case, when the type of internal waves are not known, the height dependence of the vertical gradient of refractivity can be applied for monitoring the seasonal and geographical distributions of wave activity at different levels in the atmosphere. In the case of the internal gravity waves (GW) one can measure important GW parameters by use of the vertical profile of the refractivity: the intrinsic phase speed, the horizontal wind perturbations and, under some assumptions, the intrinsic frequency as functions of height in the atmosphere. Advantages of the phase acceleration

  9. In vitro permeation and in vivo anti-inflammatory and analgesic properties of nanoscaled emulsions containing ibuprofen for topical delivery

    Directory of Open Access Journals (Sweden)

    et al

    2011-02-01

    Full Text Available Ghassan Z Abdullah1*, Muthanna F Abdulkarim1*, Ibrahim M Salman1, Omar Z Ameer1, Mun F Yam1,2, Ahmed F Mutee1, Mallikarjun Chitneni3, Elrashid S Mahdi1, Mahiran Basri4, Munavvar A Sattar1, Azmin M Noor11School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia; 2Faculty of Medicine and Health Science, Universiti Putra Malaysia, Selangor, Malaysia; 3School of Pharmacy and Health Sciences, International Medical University, Kuala Lumpur, Malaysia; 4Faculty of Science, Universiti Putra Malaysia, Selangor, Malaysia; *The first and second authors have contributed equally to this work.Introduction: As a topical delivery system, a nanoscaled emulsion is considered a good carrier of several active ingredients that convey several side effects upon oral administration, such as nonsteroidal anti-inflammatory drugs (NSAIDs.Objective: We investigated the in vitro permeation properties and the in vivo pharmacodynamic activities of different nanoscaled emulsions containing ibuprofen, an NSAID, as an active ingredient and newly synthesized palm olein esters (POEs as the oil phase.Methodology: A ratio of 25:37:38 of oil phase:aqueous phase:surfactant was used, and different additives were used for the production of a range of nanoscaled emulsions. Carbopol® 940 dispersion neutralized by triethanolamine was employed as a rheology modifier. In some circumstances, menthol and limonene were employed at different concentrations as permeation promoters. All formulae were assessed in vitro using Franz diffusion cell fitted with full-thickness rat skin. This was followed by in vivo evaluation of the anti-inflammatory and analgesic activities of the promising formulae and comparison of the effects with that of the commercially available gel.Results and discussion: Among all other formulae, formula G40 (Carbopol® 940-free formula had a superior ability in transferring ibuprofen topically compared with the reference. Carbopol® 940 significantly

  10. FALSIRE Phase II. CSNI project for Fracture Analyses of Large-Scale International Reference Experiments (Phase II). Comparison report

    International Nuclear Information System (INIS)

    Sievers, J.; Schulz, H.; Bass, R.; Pugh, C.; Keeney, J.

    1996-11-01

    A summary of Phase II of the Project for Fracture Analysis of Large-Scale International Reference Experiments (FALSIRE) is presented. A FALSIRE II Workshop focused on analyses of reference fracture experiments. More than 30 participants representing 22 organizations from 12 countries took part in the workshop. Final results for 45 analyses of the reference experiments were received from the participating analysts. For each experiment, analysis results provided estimates of variables that include temperature, crack-mouth-opening displacement, stress, strain, and applied K and J values. The data were sent electronically to the Organizing Committee, who assembled the results into a comparative data base using a special-purpose computer program. A comparative assessment and discussion of the analysis results are presented in the report. Generally, structural responses of the test specimens were predicted with tolerable scatter bands. (orig./DG)

  11. Drop sizes and particle coverage in emulsions stabilised solely by silica nanoparticles of irregular shape.

    Science.gov (United States)

    Binks, Bernard P; Fletcher, Paul D I; Holt, Benjamin L; Parker, James; Beaussoubre, Pascal; Wong, Kenneth

    2010-10-14

    We have investigated emulsions stabilised solely by partially-hydrophobised fumed silica particles which consist of a mixture of primary particles and irregularly-shaped fused aggregates and larger agglomerates. The particle wettability is controlled by varying the extent of hydrophobisation of their surfaces. This, in turn, controls the contact angle between the oil-water interface and the particle surface (θ(ow)) which affects the particle adsorption energy and the type of emulsion formed (oil-in-water, o/w or water-in-oil, w/o). Progressive particle hydrophobisation causes transitional phase inversion of the emulsions from o/w to w/o which occurs when θ(ow) = 90° and the energy of particle adsorption to the oil-water interface is maximally favourable. The key problem addressed here is to understand why the emulsion drop size passes through a minimum at the point of emulsion phase inversion. In principle, this effect could be the result of particle desorption, changes in the extent of close-packing of the adsorbed particle film (at constant particle orientation), particle re-orientation or a combination of these processes. Using measurements of emulsion drop size and the extent of particle desorption, we have derived adsorbed particle surface concentrations as a function of the energy of desorption of the particles from the oil-water interface for a range of particle concentrations and different oil-water systems. The main conclusion is that the minimum in emulsion drop size through phase inversion is mainly caused by re-orientation of the particles from a high surface area orientation when the energy of desorption is high to a low surface area orientation when the energy of desorption is low. Some particle desorption occurs but this is a secondary effect.

  12. Nuclear emulsion and high-energy physics

    International Nuclear Information System (INIS)

    Sun Hancheng; Zhang Donghai

    2008-01-01

    The history of the development of nuclear emulsion and its applications in high-energy physics, from the discovery of pion to the discovery of tau neutrino, are briefly reviewed in this paper. A new stage of development of nuclear-emulsion technique is discussed

  13. Nuclear emulsions in the OPERA experiment

    CERN Document Server

    Di Ferdinando, Donato

    2009-01-01

    The use of emulsions as particles detector has a long and successful life. The recent development of fast automatized analysis systems has allowed the use of huge amount of emulsions films with no precedence in the history of particle physics. The OPERA experiment, running in the underground Laboratori Nazionali del Gran Sasso (LNGS), for the confirmation of the neutrino oscillation in the $\

  14. Dairy-Based Emulsions: Viscosity Affects Fat Difference Thresholds and Sweetness Perception.

    Science.gov (United States)

    Zahn, Susann; Hoppert, Karin; Ullrich, Franziska; Rohm, Harald

    2013-11-27

    In complex emulsions, viscosity or viscosity-associated sensory attributes such as creaminess are important for quality assessment and product differentiation. Two sets of emulsions with fat or locust bean gum content being varied at seven levels were developed; the two emulsions at each level had similar apparent viscosity. Additionally, sugar concentration was kept constant either with respect to total emulsion, or with respect to the aqueous phase. Series of two-alternative forced choice tests were performed with one constant stimulus, and just noticeable differences were calculated using probability regression. The results show that, when viscosity was not compensated, it was easy for the subjects to (a) distinguish emulsions with different fat content when the fat content was addressed in the question, and to (b) distinguish emulsions with different fat or locust bean gum content when creaminess was addressed. For the latter descriptor, it is of minor importance whether viscosity is altered by fat content or a thickener. Weber fractions that were calculated for viscosity were approximately 0.20. The quantitative effects of viscosity on sweetness, however, depend on how product rheology was modified.

  15. Carbon Dioxide-Water Emulsions for Enhanced Oil Recovery and Permanent Sequestration of Carbon Dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, David; Golomb, Dan; Shi, Guang; Shih, Cherry; Lewczuk, Rob; Miksch, Joshua; Manmode, Rahul; Mulagapati, Srihariraju; Malepati, Chetankurmar

    2011-09-30

    This project involves the use of an innovative new invention Particle Stabilized Emulsions (PSEs) of Carbon Dioxide-in-Water and Water-in-Carbon Dioxide for Enhanced Oil Recovery (EOR) and Permanent Sequestration of Carbon Dioxide. The EOR emulsion would be injected into a semi-depleted oil reservoir such as Dover 33 in Otsego County, Michigan. It is expected that the emulsion would dislocate the stranded heavy crude oil from the rock granule surfaces, reduce its viscosity, and increase its mobility. The advancing emulsion front should provide viscosity control which drives the reduced-viscosity oil toward the production wells. The make-up of the emulsion would be subsequently changed so it interacts with the surrounding rock minerals in order to enhance mineralization, thereby providing permanent sequestration of the injected CO{sub 2}. In Phase 1 of the project, the following tasks were accomplished: 1. Perform laboratory scale (mL/min) refinements on existing procedures for producing liquid carbon dioxide-in-water (C/W) and water-in-liquid carbon dioxide (W/C) emulsion stabilized by hydrophilic and hydrophobic fine particles, respectively, using a Kenics-type static mixer. 2. Design and cost evaluate scaled up (gal/min) C/W and W/C emulsification systems to be deployed in Phase 2 at the Otsego County semi-depleted oil field. 3. Design the modifications necessary to the present CO{sub 2} flooding system at Otsego County for emulsion injection. 4. Design monitoring and verification systems to be deployed in Phase 2 for measuring potential leakage of CO{sub 2} after emulsion injection. 5. Design production protocol to assess enhanced oil recovery with emulsion injection compared to present recovery with neat CO{sub 2} flooding. 6. Obtain Federal and State permits for emulsion injection. Initial research focused on creating particle stabilized emulsions with the smallest possible globule size so that the emulsion can penetrate even low-permeability crude

  16. Development of eco-friendly submicron emulsions stabilized by a bio-derived gum.

    Science.gov (United States)

    Pérez-Mosqueda, Luis María; Ramírez, Pablo; Trujillo-Cayado, Luis Alfonso; Santos, Jenifer; Muñoz, José

    2014-11-01

    Many traditional organic solvents are being gradually replaced by ecofriendly alternatives. D-Limonene is a terpenic (bio)-solvent that fulfils the requirements to be considered a green solvent. D-Limonene sub-micron emulsions suffer from Ostwald ripening destabilization. In this study, we examined the influence of the addition of a natural gum (rosin gum) to D-limonene in order to prevent Ostwald ripening. This contribution deals with the study of emulsions formulated with a mixture of D-limonene and rosin gum as dispersed phase and Pluronic PE9400 as emulsifier. The procedure followed for the development of these formulations was based on the application of product design principles. This led to the optimum ratio rosin gum/D-limonene and subsequently to the optimum surfactant concentration. The combination of different techniques (rheology, laser diffraction and multiple light scattering) was demonstrated to be a powerful tool to assist in the prediction of the emulsions destabilization process. Not only did the addition of rosin gum highly increase the stability of these emulsions by inhibiting the Ostwald ripening, but it also reduced the emulsions droplet size. Thus, we found that stable sub-micron D-limonene-in-water emulsions have been obtained in the range 3-6 wt% Pluronic PE-9400 by means of a single-step rotor/stator homogenizing process. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Strippable core-shell polymer emulsion for decontamination of radioactive surface contamination

    International Nuclear Information System (INIS)

    Hwang, Ho-Sang; Seo, Bum-Kyoung; Lee, Kune-Woo

    2011-01-01

    In this study, the core-shell composite polymer for decontamination from the surface contamination was synthesized by the method of emulsion polymerization and blends of polymers. The strippable polymer emulsion is composed of the poly(styrene-ethyl acrylate) [poly(St-EA)] composite polymer, poly(vinyl alcohol) (PVA) and polyvinylpyrrolidone (PVP). The morphology of the poly(St-EA) composite emulsion particle was core-shell structure, with polystyrene (PS) as the core and poly(ethyl acrylate) (PEA) as the shell. Core-shell polymers of styrene (St)/ethyl acrylate (EA) pair were prepared by sequential emulsion polymerization in the presence of sodium dodecyl sulfate (SDS) as an emulsifier using ammonium persulfate (APS) as an initiator. Related tests and analysis confirmed the success in synthesis of composite polymer. The products are characterized by FT-IR spectroscopy, TGA that were used, respectively, to show the structure, the thermal stability of the prepared polymer. Two-phase particles with a core-shell structure were obtained in experiments where the estimated glass transition temperature and the morphologies of emulsion particles. Decontamination factors of the strippable polymeric emulsion were evaluated with the polymer blend contents. (author)

  18. Characteristics of W/O emulsions containing polymeric emulsifier PEG 30-dipolyhydroxystearate

    Directory of Open Access Journals (Sweden)

    Milinković Jelena R.

    2016-01-01

    Full Text Available Water-in-oil (W/O emulsions are dispersed systems which are often used in the pharmaceutical, cosmetic and food industries as products, or as carriers of active substances. It is well known that they are very unstable, so that selection of the emulsifier and properties of the oil and water phase are main factors affecting their stability. The aim of this paper was to examine the possibility of application of a lipophilic, polymeric emulsifier, PEG 30-dipolyhydroxystearate (CithrolTM DPHS, for stabilization of W/O emulsions. Behaviour of the emulsifier at W/O interfaces was determined by means of tensiometry. A series of emulsions were prepared with 20% (w/w of water and different types of oil. Droplet size, droplet size distribution, viscosity, and sedimentation stability during 30 days of storage at room temperature of the emulsions prepared with paraffin oil, olive oil, grape seed oil, and medium-chain triglycerides, stabilized with 1% CithrolTM DPHS, were determined. All investigated emulsions were stable for 30 days, except the one prepared with paraffin oil. The results of this study confirmed that PEG 30-dipolyhydroxylstearate is a good emulsifier and stabilizer of W/O emulsions which contain different types of oil. [Projekat Ministarstva nauke Republike Srbije, br. III46010

  19. Critical frequency for coalescence of emulsions in an AC electric field

    Science.gov (United States)

    Liu, Zhou; Ali, Faizi Hammad; Shum, Ho Cheung

    2017-11-01

    Applying an electric field to trigger the coalescence of emulsions has been applied in various applications which include crude oil recovery, emulsion stability characterization as well as pico-injection and droplet-based chemical reaction in microfluidics. In this work, we systematically investigated the responses of surfactant-stabilized emulsions to a controlled AC electric field using a customer-built chip. At a given amplitude of the AC voltage, we found a critical frequency beyond which the emulsions remain stable. When the frequency is decreased to below the critical value, emulsions coalesce immediately. Such critical frequency is found to be dependent of amplitude of the AC voltage, viscosity of the fluids, concentration and type of the surfactant as well as the electric conductivity of the droplet phase. Using a model based on the drainage of thin film, we have explored the mechanism behind and interpret this phenomenon systematically. Our work extends the understanding of the electro-coalescence of emulsions and can be beneficial for any applications involve the coalescence of droplets in an AC electric field.

  20. Intensification of separation of extraction emulsions in systems with tributyl phosphate in ultrasonic field

    International Nuclear Information System (INIS)

    Khavskij, N.N.; Kagerman'yan, V.S.; Kanevskij, I.N.; Kim, S.P.

    1976-01-01

    The fundamental principles have been studied determining the separation of extraction emulsions appearing in the course of the aqueous and ammonia reextraction of molybdenum from tributylphosphate (TBP) in the ultrasonic field. Piezoelectric radiators with a frequency of 0.8 to 1,0 MHz are used as ultrasonic generators. The organic extract contains 7 g/1 Mo within the hydrosolvate complex. Acceleration of the separation process has been established to take place in the ultrasound region 0.25 to 1.25 W/cm 2 for the aqueous and ammonia systems. The optimal conditions for the separation process exist within 0.5 to 0.65 W/cm 2 , they being 18 minutes for the aqueous and 16 minutes for the ammonia emulsion. It is demonstrated that as a result of the superposition of the ultrasound over the emulsions being formed by TBP with water and ammonia, the separation of the aqueous emulsions increases by a factor of 5 to 6 and of the ammonia emulsions - by a factor of 50 to 80. It is advisable that the ultrasound emulsion treatment for 5 to 10 minutes be coupled with a subsequent settling. As this takes place, the total period of the phase separation will be 18 to 20 minutes. The separation rate increases with temperature. The maximum emulsion separation acceleration is observed within 25 to 30 deg C. The possibility has been revealed to realize the process of the ultrasound intensification of the emulsion separation process by using small-sized extraction equipment

  1. Ultrafast dynamics of the acoustic vaporization of phase-change microdroplets

    NARCIS (Netherlands)

    Shpak, O.; Kokhuis, T.J.A.; Luan, Y.; Lohse, Detlef; de Jong, N.; Fowlkes, B.; Fabilli, M.; Versluis, Michel

    2013-01-01

    Acoustically sensitive emulsions are a promising tool for medical applications such as localized drug delivery. The physical mechanisms underlying the ultrasound-triggered nucleation and subsequent vaporization of these phase-change emulsions are largely unexplored. Here, the acoustic vaporization

  2. Emulsion based cast booster - a priming system

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, R.N.; Mishra, A.K. [National Institute of Rock Mechanics, KGF (India)

    2005-07-01

    This paper explores the potential of emulsion based cast booster to be used as primer to initiate bulk delivered emulsion explosives used in mines. An attempt has been made for comparative study between conventional cast booster and emulsion based cast booster in terms of the initiation process developed and their capability to develop and maintain the stable detonation process in the column explosives. The study has been conducted using a continuous velocity of detonation (VOD) measuring instrument. During this study three blasts have been monitored. In each blast two holes have been selected for study, the first hole being initiated with conventional cast booster while the other one with emulsion based cast booster. The findings of the study advocates that emulsion based cast booster is capable of efficient priming of bulk delivered column explosive with stable detonation process in the column. Further, the booster had advantages over the conventional PETN/TNT based cast booster. 5 refs., 2 figs., 1 tab., 1 photo.

  3. Radiation processing of polymer emulsion, 7

    International Nuclear Information System (INIS)

    Makuuchi, Keizo; Takagi, Toru; Nakayama, Hiroyuki.

    1983-01-01

    The film properties of thermosettable emulsions prepared by radiation method and persulfate method with same monomer composition were compared to make clear the features of the radiation-induced emulsion polymerization. The radiation method was superior to the persulfate method in the physical and chemical properties of the cured films. However, the surface gloss of the pigmented films from the radiation method were inferior to those from the persulfate method. The reason for the low surface gloss was investigated. The reaction products of glass which was used as reaction vessel with monomers were found to decrease the gloss. With ESCA (Electron Spectroscopy for Chemical Analysis) of the pigmented film it was found that there were much amount of isolated melamine resins in the radiation emulsion film than in the persufate emulsion film. The isolated melamine resins on the film surface caused by poor mutual solubility of the emulsion was found to decrease the surface gloss. (author)

  4. Crude Oil Model Emulsion Characterised by means of Near Infrared Spectroscopy and Multivariate Techniques

    DEFF Research Database (Denmark)

    Kallevik, H.; Hansen, Susanne Brunsgaard; Sæther, Ø.

    2000-01-01

    Water-in-oil emulsions are investigated by means of multivariate analysis of near infrared (NIR) spectroscopic profiles in the range 1100 - 2250 nm. The oil phase is a paraffin-diluted crude oil from the Norwegian Continental Shelf. The influence of water absorption and light scattering of the wa......Water-in-oil emulsions are investigated by means of multivariate analysis of near infrared (NIR) spectroscopic profiles in the range 1100 - 2250 nm. The oil phase is a paraffin-diluted crude oil from the Norwegian Continental Shelf. The influence of water absorption and light scattering...

  5. Enhancement of the antimicrobial properties of bacteriophage-K via stabilization using oil-in-water nano-emulsions.

    Science.gov (United States)

    Esteban, Patricia Perez; Alves, Diana R; Enright, Mark C; Bean, Jessica E; Gaudion, Alison; Jenkins, A T A; Young, Amber E R; Arnot, Tom C

    2014-01-01

    Bacteriophage therapy is a promising new treatment that may help overcome the threat posed by antibiotic-resistant pathogenic bacteria, which are increasingly identified in hospitalized patients. The development of biocompatible and sustainable vehicles for incorporation of viable bacterial viruses into a wound dressing is a promising alternative. This article evaluates the antimicrobial efficacy of Bacteriophage K against Staphylococcus aureus over time, when stabilized and delivered via an oil-in-water nano-emulsion. Nano-emulsions were formulated via thermal phase inversion emulsification, and then bacterial growth was challenged with either native emulsion, or emulsion combined with Bacteriophage K. Bacteriophage infectivity, and the influence of storage time of the preparation, were assessed by turbidity measurements of bacterial samples. Newly prepared Bacteriophage K/nano-emulsion formulations have greater antimicrobial activity than freely suspended bacteriophage. The phage-loaded emulsions caused rapid and complete bacterial death of three different strains of S. aureus. The same effect was observed for preparations that were either stored at room temperature (18-20°C), or chilled at 4°C, for up to 10 days of storage. A response surface design of experiments was used to gain insight on the relative effects of the emulsion formulation on bacterial growth and phage lytic activity. More diluted emulsions had a less significant effect on bacterial growth, and diluted bacteriophage-emulsion preparations yielded greater antibacterial activity. The enhancement of bacteriophage activity when delivered via nano-emulsions is yet to be reported. This prompts further investigation into the use of these formulations for the development of novel anti-microbial wound management strategies. © 2014 American Institute of Chemical Engineers.

  6. Effect of Surfactant Concentration in the Emulsions on the Process of Oleophilic Porous Structures Imbibition

    Directory of Open Access Journals (Sweden)

    Shtyka Olga S.

    2016-01-01

    Full Text Available The spontaneous imbibition has been a subject of the scientific interest being a background process for numerous industrial technologies and occurring in the natural environment. In literature the experimental and theoretical results regarding this phenomenon describe a media imbibition with single-phase liquids and the relation between the process rate and media characteristics. The imbibition of oleophilic porous structures with two-phase liquids, only one phase of which was wetting, is an objective of the current publication. The main purpose is to estimate the influence of both surfactant fraction and the dispersed phase concentration on the mentioned process. The imbibition rate was investigated during model experiments with stabilized oil-in-water emulsions having the dispersed phase concentrations of 10 vol%, 30 vol% and 50 vol%. The prepared emulsions differed with fraction of the added surfactant, i.e. 1 vol%, 2 vol% and 5 vol%. The obtained results allowed to conclude that at the him≥0.02 m, the dispersed phase concentration and viscosity decreased versus height. However, the raise of the surfactant fraction caused the increase of mass and height of the imbibed emulsions in porous medium. Moreover, this provided increasing of viscosity and a change of emulsions behaviour as a liquid.

  7. Relations between interfacial properties and heavy crude oil emulsions stability; Relations entre les proprietes interfaciales et la stabilite des emulsions de brut lourd

    Energy Technology Data Exchange (ETDEWEB)

    Hoebler-Poteau, S.

    2006-02-15

    Oil in water emulsions are currently being investigated to facilitate the transport of viscous heavy oils. The behavior of these emulsions is largely controlled by oil / water interfaces. The surface-active components of crude oil such as asphaltenes and naphthenic acids compete among themselves at these interfaces and also with possibly added synthetic surfactant emulsifier.Here, we present a study of dynamic interfacial tension and rheology of interfaces between water and a model oil (toluene) in which asphaltenes and other surface active molecules from crude oil are dissolved. We show that different parameters such as aging of the interface, asphaltenes concentration, the pH and salinity of the aqueous phase have a strong influence on interfacial properties of asphaltenes at the oil/water interface. Several micro-pipette experiments, in which micrometric drops have been manipulated, are described as well as small angle neutron scattering measurements. The influence of lower molecular weight surface-active species, such as the natural naphthenic acids contained in maltenes (crude oil without asphaltenes) has been investigated, and an interaction between asphaltenes and maltenes which facilitates molecular arrangement at the interface was detected. The microscopic properties of the different interfaces and the stability of the corresponding emulsions are determined to be correlated.The results obtained on model emulsions and model oil/water interfaces were found to be helpful in order to explain and predict the behavior of heavy crude oil emulsions. (author)

  8. Physics of puffing and microexplosion of emulsion fuel droplets

    Science.gov (United States)

    Shinjo, J.; Xia, J.; Ganippa, L. C.; Megaritis, A.

    2014-10-01

    The physics of water-in-oil emulsion droplet microexplosion/puffing has been investigated using high-fidelity interface-capturing simulation. Varying the dispersed-phase (water) sub-droplet size/location and the initiation location of explosive boiling (bubble formation), the droplet breakup processes have been well revealed. The bubble growth leads to local and partial breakup of the parent oil droplet, i.e., puffing. The water sub-droplet size and location determine the after-puffing dynamics. The boiling surface of the water sub-droplet is unstable and evolves further. Finally, the sub-droplet is wrapped by boiled water vapor and detaches itself from the parent oil droplet. When the water sub-droplet is small, the detachment is quick, and the oil droplet breakup is limited. When it is large and initially located toward the parent droplet center, the droplet breakup is more extensive. For microexplosion triggered by the simultaneous growth of multiple separate bubbles, each explosion is local and independent initially, but their mutual interactions occur at a later stage. The degree of breakup can be larger due to interactions among multiple explosions. These findings suggest that controlling microexplosion/puffing is possible in a fuel spray, if the emulsion-fuel blend and the ambient flow conditions such as heating are properly designed. The current study also gives us an insight into modeling the puffing and microexplosion of emulsion droplets and sprays.

  9. Olive Oil Based Emulsions in Frozen Puff Pastry Production

    Science.gov (United States)

    Gabriele, D.; Migliori, M.; Lupi, F. R.; de Cindio, B.

    2008-07-01

    Puff pastry is an interesting food product having different industrial applications. It is obtained by laminating layers of dough and fats, mainly shortenings or margarine, having specific properties which provides required spreading characteristic and able to retain moisture into dough. To obtain these characteristics, pastry shortenings are usually saturated fats, however the current trend in food industry is mainly oriented towards unsatured fats such as olive oil, which are thought to be safer for human health. In the present work, a new product, based on olive oil, was studied as shortening replacer in puff pastry production. To ensure the desired consistency, for the rheological matching between fat and dough, a water-in-oil emulsion was produced based on olive oil, emulsifier and a hydrophilic thickener agent able to increase material structure. Obtained materials were characterized by rheological dynamic tests in linear viscoelastic conditions, aiming to setup process and material consistency, and rheological data were analyzed by using the weak gel model. Results obtained for tested emulsions were compared to theological properties of a commercial margarine, adopted as reference value for texture and stability. Obtained emulsions are characterized by interesting rheological properties strongly dependent on emulsifier characteristics and water phase composition. However a change in process temperature during fat extrusion and dough lamination seems to be necessary to match properly typical dough rheological properties.

  10. Friction and Wear Management Using Solvent Partitioning of Hydrophilic-Surface-Interactive Chemicals Contained in Boundary Layer-Targeted Emulsions

    Science.gov (United States)

    Richmond, Robert Chaffee (Inventor); Schramm, Jr., Harry F. (Inventor); Defalco, Francis G. (Inventor)

    2015-01-01

    Lubrication additives of the current invention require formation of emulsions in base lubricants, created with an aqueous salt solution plus a single-phase compound such that partitioning within the resulting emulsion provides thermodynamically targeted compounds for boundary layer organization thus establishing anti-friction and/or anti-wear. The single-phase compound is termed "boundary layer organizer", abbreviated BLO. These emulsion-contained compounds energetically favor association with tribologic surfaces in accord with the Second Law of Thermodynamics, and will organize boundary layers on those surfaces in ways specific to the chemistry of the salt and BLO additives. In this way friction modifications may be provided by BLOs targeted to boundary layers via emulsions within lubricating fluids, wherein those lubricating fluids may be water-based or oil-based.

  11. Osmosis-driven viscous fingering of oil-in-water emulsions

    Science.gov (United States)

    Liu, Ying; Rallabandi, Bhargav; Baskaran, Mrudhula; Stone, Howard

    2017-11-01

    Viscous fingering occurs when a low viscosity fluid invades a more viscous fluid. Fingering of two miscible fluids is more complicated than that of immiscible fluids in that there is no sharp fluid-fluid interface and diffusion occurs between the phases. We experimentally studied the fingering of two miscible fluids: an oil-in-water emulsion and a sodium chloride solution. When the concentration of sodium chloride in the water phase in the emulsion exceeds that in the sodium chloride solution, the consequent osmotic flow automatically facilitates the occurrence of the fingering. On the contrary, when the sodium chloride solution has higher concentration, the spreading of emulsion is more uniform than the case without the concentration difference. We provide a model to rationalize and quantify these observations.

  12. Impact of fat and water crystallization on the stability of hydrogenated palm oil-in-water emulsions stabilized by a nonionic surfactant.

    Science.gov (United States)

    Thanasukarn, Parita; Pongsawatmanit, Rungnaphar; McClements, D Julian

    2006-05-17

    The influence of (0-40 wt %) sucrose and (0 and 150 mmol/kg) sodium chloride on the physical properties of 20 wt % hydrogenated palm oil-in-water emulsions stabilized by 2 wt % Tween 20 after crystallization of the oil phase only or both the oil and water phases has been examined. Emulsion stability was assessed by differential scanning calorimetry measurements of fat destabilization after cooling-heating cycles and by measurements of mean particle size, percent destabilized fat, and percent free oil obtained from gravitational separation after isothermal storage (at -40 to +37 degrees C). At storage temperatures where the oil phase was partially crystalline and the water was completely liquid, the emulsions were unstable to droplet coalescence and oiling off because of partial coalescence. Both NaCI and sucrose increased the extent of partial coalescence in the emulsions. At storage temperatures where both oil and water crystallized, the emulsions were completely destabilized. The stability of the emulsions to freezing and thawing could be improved somewhat by adding sucrose (>20 wt %). Emulsions stabilized by whey proteins were shown to have better freeze-thaw stability than those stabilized by Tween 20, especially in the presence of sucrose. These results may help formulate food emulsions with improved freeze-thaw stability.

  13. Emulsion-based encapsulation and delivery of nanoparticles for the controlled release of alkalinity within the subsurface environment

    Science.gov (United States)

    Ramsburg, C. A.; Muller, K.; Gill, J.

    2012-12-01

    Many current approaches to managing groundwater contamination rely on further advances in amendment delivery in order to initiate and sustain contaminant degradation or immobilization. In fact, limited or ineffective delivery is often cited when treatment objectives are not attained. Emulsions, specifically oil-in-water emulsions, have demonstrated potential to aid delivery of remediation amendments. Emulsions also afford opportunities to control the release of active ingredients encapsulated within the droplets. Our research is currently focused on the controlled release of nanoparticle-based buffering agents using oil-in-water emulsions. This interest is motivated by the fact that chemical and biological processes employed for the remediation and stewardship of contaminated sites often necessitate control of pH during treatment and, in some cases, long thereafter. Alkalinity-release nanoparticles (e.g., CaCO3, MgO) were suspended within soybean oil and subsequently encapsulated by through the creation of oil-in-water emulsions. These oil-in-water emulsions are designed to have physical properties which are favorable for subsurface delivery (nominal properties: 1 g/mL density; 10 cP viscosity; and 1.5 μm droplet diameter). Buffer capacity titrations suggest that MgO particles are moderately more accessible within the oil phase and nearly twice as effective (on a per mass basis) at releasing alkalinity (as compared to the CaCO3 particles). Results from experiments designed to assess the release kinetics suggest that a linear driving force model is capable of describing the release process and mass transfer coefficients are constant through the reactive life of the emulsion. The release kinetics in emulsions containing MgO particles were found to be three orders of magnitude faster than those quantified for emulsions containing CaCO3. The slower release kinetics of the emulsions containing CaCO3 particles may prove beneficial when considering pH control at sites

  14. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Colombia

    International Nuclear Information System (INIS)

    1984-01-01

    A full report has been released describing the findings of the International Uranium Resources Evaluation Project (IUREP) Orientation Phase Mission to Colombia. The Mission suggests that the speculative uranium resources of the country could be within the very wide range of 20 000 tonnes of 220 000 tonnes of uranium metal. The Mission finds that the area with the highest potential is the Llanos Orientales (Interior Zone), which has the potential of hosting quartz-pebble conglomerate deposits, Proterozoic unconformity-related deposits and sandstone deposits. The Mission recommends that approximately US$80 million should be expended in a phased ten-year exploration programme. It is likely that the majority of the funds will be needed for drilling, followed by ground surveys and airborne radiometry. It is the opinion of the Mission that the considerable funds required for the proposed programme could most suitably be raised by inviting national or foreign commercial organizations to participate under a shared production agreement. (author)

  15. Observational study: microgravity testing of a phase-change reference on the International Space Station.

    Science.gov (United States)

    Topham, T Shane; Bingham, Gail E; Latvakoski, Harri; Podolski, Igor; Sychev, Vladimir S; Burdakin, Andre

    2015-01-01

    Orbital sensors to monitor global climate change during the next decade require low-drift rates for onboard thermometry, which is currently unattainable without on-orbit recalibration. Phase-change materials (PCMs), such as those that make up the ITS-90 standard, are seen as the most reliable references on the ground and could be good candidates for orbital recalibration. Space Dynamics Lab (SDL) has been developing miniaturized phase-change references capable of deployment on an orbital blackbody for nearly a decade. Improvement of orbital temperature measurements for long duration earth observing and remote sensing. To determine whether and how microgravity will affect the phase transitions, SDL conducted experiments with ITS-90 standard material (gallium, Ga) on the International Space Station (ISS) and compared the phase-change temperature with earth-based measurements. The miniature on-orbit thermal reference (MOTR) experiment launched to the ISS in November 2013 on Soyuz TMA-11M with the Expedition 38 crew and returned to Kazakhstan in March 2014 on the Soyuz TMA-10 spacecraft. MOTR tested melts and freezes of Ga using repeated 6-h cycles. Melt cycles obtained on the ground before and after launch were compared with those obtained on the ISS. To within a few mK uncertainty, no significant difference between the melt temperature of Ga at 1 g and in microgravity was observed.

  16. Latest Developments in Nuclear Emulsion Technology

    Science.gov (United States)

    Morishima, Kunihiro

    Nuclear emulsion is high sensitive photographic film used for detection of three-dimensional trajectory of charged particles. These trajectories are recorded as tracks consist of a lot of silver grains. The size of silver grain is about 1 μm, so that nuclear emulsion has submicron three-dimensional spatial resolution, which gives us a few mrad three-dimensional angular resolution. The important technical progress was speed-up of the read-out technique of nuclear emulsions built with optical microscope system. We succeeded in developing a high-speed three-dimensional read-out system named Super Ultra Track Selector (S-UTS) with the operating read-out speed of approximately 50 cm2/h. Nowadays we are developing the nuclear emulsion gel independently in Nagoya University by introducing emulsion gel production machine. Moreover, we are developing nuclear emulsion production technologies (gel production, poring and mass production). In this paper, development of nuclear emulsion technologies for the OPERA experiment, applications by the technologies and current development are described.

  17. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Turkey

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Turkey. The IUREP Orientation Phase mission to Turkey estimates that the Speculative Resources of that country fall within the range of 21 000 to 55 000 tonnes of uranium. This potential is expected to lie in areas of Neogene and possibly other Tertiary sediments, in particular in the areas of the Menderes Massif and Central Anatolia. The mission describes a proposed exploration programme with expenditures over a five year period of between $80 million and $110 million, with nearly half of the amount being spent on drilling. (author)

  18. IFMIF (International Fusion Materials Irradiation Facility) key element technology phase interim report

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Hiroo; Ida, Mizuho; Sugimoto, Masayoshi; Takeuchi, Hiroshi; Yutani, Toshiaki (eds.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-03-01

    Activities of International Fusion Materials Irradiation Facility (IFMIF) have been performed under an IEA collaboration since 1995. IFMIF is an accelerator-based deuteron (D{sup +})-lithium (Li) neutron source designed to produce an intense neutron field (2 MW/m{sup 2}, 20 dpa/year for Fe) in a volume of 500 cm{sup 3} for testing candidate fusion materials. In 2000, a 3 year Key Element technology Phase (KEP) of IFMIF was started to reduce the key technology risk factors. This interim report summarizes the KEP activities until mid 2001 in the major project work-breakdown areas of accelerator, target, test facilities and design integration. (author)

  19. Formulation and characterization of a multiple emulsion containing 1% L-ascorbic acid

    Directory of Open Access Journals (Sweden)

    Naveed Akhtar

    2010-04-01

    Full Text Available The purpose of the study was to prepare a stable multiple emulsion containing a skin anti-aging agent and using paraffin oil. Vitamin C, was incorporated into the inner aqueous phase of water-in-oil-in-water (w/o/w multiple emulsion at a concentration of 1%. Multiple emulsion was prepared by two step method. Stability studies were performed at different accelerated conditions, i.e. 8 oC (in refrigerator, 25 oC (in oven, 40 oC (in oven, and 40 oC at 75% RH (in stability cabin for 28 days to predict the stability of formulations. Different parameters, namely pH, globule size, electrical conductivity and effect of centrifugation (simulating gravity were determined during stability studies. Data obtained was evaluated statistically using ANOVA two way analyses and LSD tests. Multiple emulsion formulated was found to be stable at lower temperatures (i.e. 8 and 25 oC for 28 days. No phase separation was observed in the samples during stability testing. It was found that there was no significant change (p > 0.05 in globule sizes in most of the samples kept at various conditions. Insignificant changes (p > 0.05 in both pH and conductivity values were determined for the samples kept at 8, 40, and 40 oC at 75% RH, throughout the study period. Further studies are needed to formulate more stable emulsions with other emulsifying agents.

  20. Evaporation and Condensation Flows of a Vapor-Gas Mixture from or onto the Condensed Phase with an Internal Structure

    National Research Council Canada - National Science Library

    Onishi, Yoshimoto; Yamada, Ken

    2005-01-01

    Transient motions of a vapor-gas mixture due to the evaporation and condensation processes from or onto the plane condensed phase, with a temperature field as its internal structure, have been studied...

  1. Long-term characteristics of nuclear emulsion

    International Nuclear Information System (INIS)

    Naganawa, N; Kuwabara, K

    2010-01-01

    Long-term characteristics of the nuclear emulsion so called 'OPERA film' used in the neutrino oscillation experiment, OPERA, has been studied for 8 years since its production or refreshing after it. In the results, it turned out to be excellent in sensitivity, amount of random noise, and refreshing characteristics. The retention capacity of latent image of tracks was also studied. The result will open the way to the recycling of 7,000,000 emulsion films which will remain not developed after 5 years of OPERA's run, and other long-term experiments with emulsion.

  2. Fast automated scanning of OPERA emulsion films

    CERN Document Server

    Sirri, G.

    2007-01-01

    The use of nuclear emulsions to record tracks of charged particles with an accuracy of better than 1 micron is possible in large physics experiments thanks to the recent improvements in the industrial production of emulsions and to the development of fast automated microscopes. The European Scanning System (ESS) is a fast automatic system developed for the mass scanning of the emulsions of the OPERA experiment, which requires microscopes with scanning speeds of about 20 cm$^2$/h. Recent improvements in the technique and measurements with ESS are reported.

  3. Volatile release and structural stability of β-lactoglobulin primary and multilayer emulsions under simulated oral conditions.

    Science.gov (United States)

    Benjamin, O; Silcock, P; Beauchamp, J; Buettner, A; Everett, D W

    2013-09-01

    The relationship between emulsion structure and the release of volatile organic compounds (VOCs) was investigated using a model mouth system under oral conditions (tongue mastication, artificial saliva, pH and salt). The VOCs were monitored on-line by proton transfer reaction mass spectrometry (PTR-MS). Two types of emulsion system were compared: primary and multilayer oil-in-water (P-O/W, M-O/W) emulsions consisting of soy oil coated by β-lactoglobulin and pectin layers. The P-O/W emulsions showed intensive flocculation at pH 5 and above 200 mM NaCl where the electrostatic repulsive charge was at a minimum. Bridging and depletion flocculation were mostly observed for P-O/W emulsions containing artificial saliva with 1 wt% mucin. The VOC release was found to increase when the emulsion droplets flocculated, thus changing the oil volume phase distribution. The adsorbed pectin layer stabilised the emulsion structure under conditions of short-time oral processing, and hindered the release of hydrophobic VOCs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Emulsions from a Culinary Perspective

    DEFF Research Database (Denmark)

    Helgesdotter, Guro

    , because of its emulsion, foam and suspension properties. This thesis explores the structure and parameters influencing product diversity in hollandaise sauce and similar products from a culinary point of view. It can therefore be regarded as an investigation in the field of molecular gastronomy. When...... consulting the culinary literature and culinary professionals, it became evident that large variations existed both in the preparation techniques and regarding the ingredients used in hollandaise sauce. It was unlikely that all these variations could lead to sauces having the same sensory properties...... influenced the research aims and topics, and hollandaise sauce was chosen as the research subject in this PhD to gain knowledge about how the culinary variation regarding hollandaise sauce production influences the product. This knowledge may benefit chefs in their daily work and may stimulate culinary...

  5. Emulsion type dry cleaning system

    International Nuclear Information System (INIS)

    Kohanawa, Osamu; Matsumoto, Hiroyo.

    1988-01-01

    Protective clothing against radioactive contamination used in the radiation controlled areas of nuclear plants has been washed by the same wet washing as used for underwear washing, but recently dry cleaning is getting used in place of wet washing, which generates a large quantity of laundry drain. However, it was required to use wet washing once every five to ten dry cleanings for washing protective clothing, because conventional dry cleaning is less effective in removing water-soluble soils. Therefore, in order to eliminate wet washing, and to decrease the quantity of laundry drains, the emulsion type dry cleaning system capable of removing both oil-soluble and water-soluble soils at a time has been developed. The results of developmental experiments and actual application are presented in this paper. (author)

  6. Crude Oil Model Emulsion Characterised by means of Near Infrared Spectroscopy and Multivariate Techniques

    DEFF Research Database (Denmark)

    Kallevik, H.; Hansen, Susanne Brunsgaard; Sæther, Ø.

    2000-01-01

    Water-in-oil emulsions are investigated by means of multivariate analysis of near infrared (NIR) spectroscopic profiles in the range 1100 - 2250 nm. The oil phase is a paraffin-diluted crude oil from the Norwegian Continental Shelf. The influence of water absorption and light scattering...... of the water droplets are shown to be strong. Despite the strong influence of the water phase, the NIR technique is still capable of predicting the composition of the investigated oil phase....

  7. Use of olive oil-in-water gelled emulsions in model turkey breast emulsions

    Science.gov (United States)

    Serdaroğlu, M.; Öztürk, B.

    2017-09-01

    Today, gelled emulsion systems offer a novel possibility in lipid modification of meat products. In this study, we aimed to investigate the quality characteristics of model turkey emulsions that were prepared with olive oil-in-water gelled emulsion (GE) as partial or total beef fat replacer. The results indicated that while most of the GE treatments showed equivalent emulsion characteristics in terms of emulsion stability, water-holding capacity and cook yield, utilization of 100% GE as the lipid source could increase total expressible fluid of the model turkey emulsion and thus negatively affect the quality. Utilization of GE was effective in total fat reduction, as the model turkey emulsions formulated with more than 50% GE had significantly lower fat content compared to full-beef fat control model emulsion. However, beef fat replacement with GE produced considerable changes in colour parameters. Finally, it was concluded that utilization of GE as a partial beef fat replacer has good potential to enhance stability and reduce total fat in turkey meat emulsion products.

  8. Internal Dose from Food and Drink Ingestion in the Early Phase after the Accident

    Science.gov (United States)

    Kawai, Masaki; Yoshizawa, Nobuaki; Hirakawa, Sachiko; Murakami, Kana; Takizawa, Mari; Sato, Osamu; Takagi, Shunji; Miyatake, Hirokazu; Takahashi, Tomoyuki; Suzuki, Gen

    2017-09-01

    Activity concentrations in food and drink, represented by water and vegetables, have been monitored continuously since the Fukushima Daiichi Nuclear Power Plant accident, with a focus on radioactive cesium. On the other hand, iodine-131 was not measured systematically in the early phase after the accident. The activity concentrations of iodine-131 in food and drink are important to estimate internal exposure due to ingestion pathway. When the internal dose from ingestion in the evacuation areas is estimated, water is considered as the main ingestion pathway. In this study, we estimated the values of activity concentrations in water in the early phase after the accident, using a compartment model as an estimation method. The model uses measurement values of activity concentration and deposition rate of iodine-131 onto the ground, which is calculated from an atmospheric dispersion simulation. The model considers how drinking water would be affected by radionuclides deposited into water. We estimated the activity concentrations of water on Kawamata town and Minamisouma city during March of 2011 and the committed effective doses were 0.08 mSv and 0.06 mSv. We calculated the transfer parameters in the model for estimating the activity concentrations in the areas with a small amount of measurement data. In addition, we estimated the committed effective doses from vegetables using atmospheric dispersion simulation and FARMLAND model in case of eating certain vegetables as option information.

  9. Leaching of plasticizers from polyvinylchloride perfusion lines by different lipid emulsions for premature infants under clinical conditions.

    Science.gov (United States)

    Faessler, David; McCombie, Gregor; Biedermann, Maurus; Felder, Florian; Subotic, Ulrike

    2017-03-30

    Plasticizers migrate from polyvinylchloride (PVC) infusion systems into lipid emulsions. The aim of this study was to investigate the leaching of different plasticizers from PVC perfusion lines by a selection of lipid emulsions under clinical conditions. Seven PVC perfusion lines with an equal length of 150cm and three internal diameters were perfused with three lipid emulsions: Intralipid ® 20%, ClinOleic ® 20% and SMOFlipid ® 20%, mimicking clinical conditions. The concentrations of the plasticizers were measured directly in the emulsions by gas chromatography - mass spectrometry. Of the four plasticizers examined in this study, di (2-ethylhexyl) phthalate (DEHP) leached the most and was found, on average, at 46.5μg/ml in the emulsions - around one order of magnitude higher than the other plasticizers. This study demonstrates that the leaching of DEHP by lipid emulsions in conditions of total parenteral nutrition is many times higher than should be accepted and higher when compared to the other plasticizers. There was no significant difference in leaching of plasticizers in relation to the type of lipid emulsion. The influence of tube diameter on the leaching rate of plasticizers should be taken into account especially in particular exposed patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Gender differences in triple jump phase ratios and arm swing motion of international level athletes

    Directory of Open Access Journals (Sweden)

    Vassilios Panoutsakopoulos

    2016-12-01

    Full Text Available Background: Female triple jumping is a relatively new athletics event. A limited number of researchers have focused on comparing male and female jumpers competing in international events, resulting in scarce findings in the literature regarding gender differences of the determinants of triple jump performance. Objective: The aim of the study was to examine the possible gender differences in the approach step characteristics, the spatiotemporal parameters of the separate phases of the triple jump as performed by athletes participating in sub-elite international events. Methods: The male and female participants of the 2015 European Team Championships triple jump event were recorded with a panning video camera. Approach speed was measured using photocells. Kinematical parameters were extracted using the APAS WIZARD 13.3.0.3 software. The relationships between the examined parameters and the actual triple jump performance were examined with Pearson's correlation analysis. Repeated measures ANOVA and chi-square statistical tests were run to examine the significance of the differences between genders. Results: Approach speed significantly correlated with the actual jumping distance in both males and females (p < .05. Significant gender differences (p < .05 existed concerning basic kinematical parameters. Men were found to have larger average horizontal speed of the 11 m to 1 m segment of the final approach, step length of the final six steps of the approach, step frequency of the final two steps, actual phase distances and percentage distribution of the step. Women, unlike men, used solely single arm swing techniques. No athlete executed the jump using a jump dominated technique. Conclusions: Gender differences in triple jump performance lies upon the kinematical parameters of the final two steps of the approach, the length of the step phase and the support time for the jump. The technique elements of the penultimate step are suggested to

  11. Size determinations of colloidal fat emulsions

    DEFF Research Database (Denmark)

    Kuntsche, Judith; Klaus, Katrin; Steiniger, Frank

    2009-01-01

    Size and size distributions of colloidal dispersions are of crucial importance for their performance and safety. In the present study, commercially available fat emulsions (Lipofundin N, Lipofundin MCT and Lipidem) were analyzed by photon correlation spectroscopy, laser diffraction with adequate ...

  12. Interfacial rheology of model particles at liquid interfaces and its relation to (bicontinuous) Pickering emulsions

    Science.gov (United States)

    Thijssen, J. H. J.; Vermant, J.

    2018-01-01

    Interface-dominated materials are commonly encountered in both science and technology, and typical examples include foams and emulsions. Conventionally stabilised by surfactants, emulsions can also be stabilised by micron-sized particles. These so-called Pickering–Ramsden (PR) emulsions have received substantial interest, as they are model arrested systems, rather ubiquitous in industry and promising templates for advanced materials. The mechanical properties of the particle-laden liquid–liquid interface, probed via interfacial rheology, have been shown to play an important role in the formation and stability of PR emulsions. However, the morphological processes which control the formation of emulsions and foams in mixing devices, such as deformation, break-up, and coalescence, are complex and diverse, making it difficult to identify the precise role of the interfacial rheological properties. Interestingly, the role of interfacial rheology in the stability of bicontinuous PR emulsions (bijels) has been virtually unexplored, even though the phase separation process which leads to the formation of these systems is relatively simple and the interfacial deformation processes can be better conceptualised. Hence, the aims of this topical review are twofold. First, we review the existing literature on the interfacial rheology of particle-laden liquid interfaces in rheometrical flows, focussing mainly on model latex suspensions consisting of polystyrene particles carrying sulfate groups, which have been most extensively studied to date. The goal of this part of the review is to identify the generic features of the rheology of such systems. Secondly, we will discuss the relevance of these results to the formation and stability of PR emulsions and bijels.

  13. Experiments on muon radiography with emulsion track detectors

    International Nuclear Information System (INIS)

    Aleksandrov, Andrey; Bagulya, Alexander; Baklagin, Sergei; Chernyavsky, Mikhail; Galkin, Vladimir; Grachev, Victor; Konovalova, Nina; Managadze, Alexander; Polukhina, Natalya; Roganova, Tatiana; Starkov, Nikolai; Shchedrina, Tatiana; Tioukov, Valeri; Vladymirov, Mykhailo; Zemskova, Svetlana

    2016-01-01

    Muon radiography is a method of study the internal structure of large natural and industrial objects based on sensing an object with a flux of cosmic muons with their subsequent registration and analysis of the pattern of their dispersion, or conplete (or partial) absorption. The Lebedev Physical Institute of the Russian Academy of Sciences and the Skobeltsyn Institute of Nuclear Physics of Moscow State University have started a series of muon radiography experiments with nuclear emulsion detectors. As a result, the optimal conditions for experiment arrangement have been determined, algorithms of data processing have been worked out, and peculiarities of the method have been ultimately investigated

  14. Analysis of a microscale 'Saturation Phase-change Internal Carnot Engine'

    International Nuclear Information System (INIS)

    Lurie, Eli; Kribus, Abraham

    2010-01-01

    A micro heat engine, based on a cavity filled with a stationary working fluid under liquid-vapor saturation conditions and encapsulated by two membranes, is described and analyzed. This engine design is easy to produce using MEMS technologies and is operated with external heating and cooling. The motion of the membranes is controlled such that the internal pressure and temperature are constant during the heat addition and removal processes, and thus the fluid executes a true internal Carnot cycle. A model of this Saturation Phase-change Internal Carnot Engine (SPICE) was developed including thermodynamic, mechanical and heat transfer aspects. The efficiency and maximum power of the engine are derived. The maximum power point is fixed in a three-parameter space, and operation at this point leads to maximum power density that scales with the inverse square of the engine dimension. Inclusion of the finite heat capacity of the engine wall leads to a strong dependence of performance on engine frequency, and the existence of an optimal frequency. Effects of transient reverse heat flow, and 'parasitic heat' that does not participate in the thermodynamic cycle are observed.

  15. The efficacy of compounds with different polarities as antioxidant in emulsions with omega-3 lipids

    DEFF Research Database (Denmark)

    Sørensen, Ann-Dorit Moltke; Nielsen, Nina Skall; Decker, Eric A.

    2011-01-01

    According to the so-called polar paradox hypothesis, the efficacy of an antioxidant in emulsions is highly affected by its polarity and thereby location in the different phases. However, other factors also affect the efficacy of antioxidants in multiphase systems. The aim of this study was to eva...

  16. Dynamics of controlled release systems based on water-in-water emulsions: A general theory

    NARCIS (Netherlands)

    Sagis, L.M.C.

    2008-01-01

    Phase-separated biopolymer solutions, and aqueous dispersions of hydrogel beads, liposomes, polymersomes, aqueous polymer microcapsules, and colloidosomes are all examples of water-in-water emulsions. These systems can be used for encapsulation and controlled release purposes, in for example food or

  17. and α-Fe 2 O 3 nano powders synthesized by emulsion precipitation

    African Journals Online (AJOL)

    Nano crystals of γ-Fe2O3 (maghemite) were synthesized by emulsion precipitation method using kerosene as oil phase, SPAN- 80 (sorbitane monooleate) as the surfactant and sodium hydroxide as the precipitating agent. The characterization of the samples by FTIR (Fourier transform infra-red) and XRD (X-ray diffraction) ...

  18. An oral delivery system for indomethicin engineered from cationic lipid emulsions and silica nanoparticles

    DEFF Research Database (Denmark)

    Simovic, Spomenka; Hui, He; Song, Yunmei

    2010-01-01

    We report on a porous silica-lipid hybrid microcapsule (SLH) oral delivery system for indomethacin fabricated from Pickering emulsion templates, where the drug forms an electrostatic complex with cationic lipid present in the oil phase. Dry SLH microcapsules prepared either by spray drying...

  19. Influence of propylene glycol on aqueous silica dispersions and particle-stabilized emulsions.

    Science.gov (United States)

    Binks, Bernard P; Fletcher, Paul D I; Thompson, Michael A; Elliott, Russell P

    2013-05-14

    We have studied the influence of adding propylene glycol to both aqueous dispersions of fumed silica nanoparticles and emulsions of paraffin liquid and water stabilized by the same particles. In the absence of oil, aerating mixtures of aqueous propylene glycol and particles yields either stable dispersions, aqueous foams, climbing particle films, or liquid marbles depending on the glycol content and particle hydrophobicity. The presence of glycol in water promotes particles to behave as if they are more hydrophilic. Calculations of their contact angle at the air-aqueous propylene glycol surface are in agreement with these findings. In the presence of oil, particle-stabilized emulsions invert from water-in-oil to oil-in-water upon increasing either the inherent hydrophilicity of the particles or the glycol content in the aqueous phase. Stable multiple emulsions occur around phase inversion in systems of low glycol content, and completely stable, waterless oil-in-propylene glycol emulsions can also be prepared. Accounting for the surface energies at the respective interfaces allows estimation of the contact angle at the oil-polar phase interface; reasonable agreement between measured and calculated phase inversion conditions is found assuming no glycol adsorption on particle surfaces.

  20. Lipophilization of dihydrocaffeic acid affects its antioxidative properties in fish‐oil‐enriched emulsions

    DEFF Research Database (Denmark)

    Sørensen, Ann-Dorit Moltke; Nielsen, Nina Skall; Yang, Zhiyong

    2012-01-01

    The aim of the present study was to evaluate the antioxidative effect of lipophilized dihydrocaffeic acid, i.e., octyl dihydrocaffeate and oleyl dihydrocaffeate. Furthermore, the relationship between the measured efficacy of the antioxidants in emulsions, their partitioning into different phases ...

  1. Effect of lipophilization on the distribution and reactivity of ingredients in emulsions

    NARCIS (Netherlands)

    Leong, Wai Fun; Berton-Carabin, C.C.; Elias, Ryan J.; Lecomte, Jérôme; Villeneuve, Pierre; Zhao, Yu; Coupland, John N.

    2015-01-01

    Hypothesis: The reactivity of small molecules in emulsions is believed to depend on their partitioning between phases, yet this is hard to verify experimentally in situ. In the present work, we use electron paramagnetic resonance (EPR) spectroscopy to simultaneously measure the distribution and

  2. Special photographic emulsions for high LET dosimetry

    International Nuclear Information System (INIS)

    Katz, R.

    1978-12-01

    The purpose of these investigations into photographic emulsion dosimetry is to attempt to use the photographic emulsion to mimic the response of human tissues to high LET radiations. The program therefore requires that a systematic understanding of the response of mammalian cells to ionizing radiations be achieved. We have been concerned with differences in RBE and in radiation response to both high and LET radiations, and in the interrelationship between observations with these different radiations

  3. Needleless emulsion electrospinning for the regulated delivery of susceptible proteins.

    Science.gov (United States)

    Buzgo, Matej; Filova, Eva; Staffa, Andrea Mickova; Rampichova, Michala; Doupnik, Miroslav; Vocetkova, Karolina; Lukasova, Vera; Kolcun, Radka; Lukas, David; Necas, Alois; Amler, Evzen

    2018-03-01

    In the present work, we developed a novel needleless emulsion electrospinning technique that improves the production rate of the core/shell production process. The nanofibres are based on poly-ε-caprolactone (PCL) as a continuous phase combined with a droplet phase based on Pluronic F-68 (PF-68). The PCL-PF-68 nanofibres show a time-regulated release of active molecules. Needleless emulsion electrospinning was used to encapsulate a diverse set of compounds to the core phase [i.e. 5-(4,6-dichlorotriazinyl) aminofluorescein -PF-68, horseradish peroxidase, Tetramethylrhodamine-dextran, insulin growth factor-I, transforming growth factor-β and basic fibroblast growth factor]. In addition, the PF-68 facilitates the preservation of the bioactivity of delivered proteins. The system's potential was highlighted by an improvement in the metabolic activity and proliferation of mesenchymal stem cells. The developed system has the potential to deliver susceptible molecules in tissue-engineering applications. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Method for reducing peak phase current and decreasing staring time for an internal combustion engine having an induction machine

    Science.gov (United States)

    Amey, David L.; Degner, Michael W.

    2002-01-01

    A method for reducing the starting time and reducing the peak phase currents for an internal combustion engine that is started using an induction machine starter/alternator. The starting time is reduced by pre-fluxing the induction machine and the peak phase currents are reduced by reducing the flux current command after a predetermined period of time has elapsed and concurrent to the application of the torque current command. The method of the present invention also provides a strategy for anticipating the start command for an internal combustion engine and determines a start strategy based on the start command and the operating state of the internal combustion engine.

  5. Photopolymerization of complex emulsions with irregular shapes fabricated by multiplex coaxial flow focusing

    Science.gov (United States)

    Wu, Qiang; Yang, Chaoyu; Yang, Jianxin; Huang, Fangsheng; Liu, Guangli; Zhu, Zhiqiang; Si, Ting; Xu, Ronald X.

    2018-02-01

    We fabricate complex emulsions with irregular shapes in the microscale by a simple but effective multiplex coaxial flow focusing process. A multiphase cone-jet structure is steadily formed, and the compound liquid jet eventually breaks up into Janus microdroplets due to the perturbations propagating along the jet interfaces. The microdroplet shapes can be exclusively controlled by interfacial tensions of adjacent phases. Crescent-moon-shaped microparticles and microcapsules with designated structural characteristics are further produced under ultraviolet light of photopolymerization after removing one hemisphere of the Janus microdroplets. These complex emulsions have potential applications in bioscience, food, functional materials, and controlled drug delivery.

  6. Investigation of gas-phase decontamination of internally radioactively contaminated gaseous diffusion process equipment and piping

    International Nuclear Information System (INIS)

    Bundy, R.D.; Munday, E.B.

    1991-01-01

    Construction of the gaseous diffusion plants (GDPs) was begun during World War 2 to produce enriched uranium for defense purposes. These plants, which utilized UF 6 gas, were used primarily for this purpose through 1964. From 1959 through 1968, production shifted primarily to uranium enrichment to supply the nuclear power industry. Additional UF 6 -handling facilities were built in feed and fuel-processing plants associated with the uranium enrichment process. Two of the five process buildings at Oak ridge were shut down in 1964. Uranium enrichment activities at Oak Ridge were discontinued altogether in 1985. In 1987, the Department of Energy (DOE) decided to proceed with a permanent shutdown of the Oak Ridge Gaseous Diffusion Plant (ORGDP). DOE intends to begin decommissioning and decontamination (D ampersand D) of ORGDP early in the next century. The remaining two GDPs are expected to be shut down during the next 10 to 40 years and will also require D ampersand D, as will the other UF 6 -handling facilities. This paper presents an investigation of gas- phase decontamination of internally radioactively contaminated gaseous diffusion process equipment and piping using powerful fluorinating reagents that convert nonvolatile uranium compounds to volatile UF 6 . These reagents include ClF 3 , F 2 , and other compounds. The scope of D ampersand D at the GDPs, previous work of gas-phase decontamination, four concepts for using gas-phase decontamination, plans for further study of gas-phase decontamination, and the current status of this work are discussed. 13 refs., 15 figs

  7. Preparation of a multiple emulsion based on pectin-whey protein complex for encapsulation of saffron extract nanodroplets.

    Science.gov (United States)

    Faridi Esfanjani, Afshin; Jafari, Seid Mahdi; Assadpour, Elham

    2017-04-15

    The present study illustrates a simple and practical way to produce an adequate delivery system of bioactive compounds of saffron by protein-polysaccharide complex. Frist, crocin, safranal, and picrocrocin were loaded in nanodroplets (WPC)-maltodextrin or WPC-pectin-maltodextrin through water in oil in water (W/O/W) multiple emulsions. The stability and release of loaded crocin, safranal, and picrocrocin in multiple emulsions were investigated during 22days storage. The produced multiple emulsion by WPC-pectin-maltodextrin along with 5% inner aqueous phase showed a high stability and low release of encapsulated compounds over time. This emulsion also provided a high protection of crocin, safranal, and picrocrocin in the gastric condition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Factors governing partial coalescence in oil-in-water emulsions.

    Science.gov (United States)

    Fredrick, Eveline; Walstra, Pieter; Dewettinck, Koen

    2010-01-15

    The consequences of the instability mechanism partial coalescence in oil-in-water food emulsions show a discrepancy. On the one hand, it needs to be avoided in order to achieve an extended shelf life in food products like sauces, creams and several milk products. On the other hand, during the manufacturing of products like ice cream, butter and whipped toppings partial coalescence is required to achieve the desired product properties. It contributes to the structure formation, the physicochemical properties (stability, firmness,...) and the sensory perception, like fattiness and creaminess of the final food products. This review critically summarises the findings of partial coalescence in oil-in-water emulsions in order to provide insight in how to enhance and retard it. Next to the pioneering work, a large set of experimental results of more recent work is discussed. First, the general mechanism of partial coalescence is considered and a distinction is made between partial and 'true' coalescence. The main differences are: the required solid particles in the dispersed oil phase, the formation of irregular clusters and the increased aggregation rate. Second, the kinetics of partial coalescence is discussed. In more detail, potential parameters affecting the rate of partial coalescence are considered by means of the encounter frequency and capture efficiency of the fat globules. The flow conditions, the fat volume fraction and the physicochemical properties of continuous aqueous phase affect both the encounter frequency and capture efficiency while the actual temperature, temperature history and the composition and formulation of the emulsion mainly affect the capture efficiency. Copyright 2009 Elsevier B.V. All rights reserved.

  9. A Modular Microfluidic Device via Multimaterial 3D Printing for Emulsion Generation.

    Science.gov (United States)

    Ji, Qinglei; Zhang, Jia Ming; Liu, Ying; Li, Xiying; Lv, Pengyu; Jin, Dongping; Duan, Huiling

    2018-03-19

    3D-printing (3DP) technology has been developing rapidly. However, limited studies on the contribution of 3DP technology, especially multimaterial 3DP technology, to droplet-microfluidics have been reported. In this paper, multimaterial 3D-printed devices for the pneumatic control of emulsion generation have been reported. A 3D coaxial flexible channel with other rigid structures has been designed and printed monolithically. Numerical and experimental studies have demonstrated that this flexible channel can be excited by the air pressure and then deform in a controllable way, which can provide the active control of droplet generation. Furthermore, a novel modular microfluidic device for double emulsion generation has been designed and fabricated, which consists of three modules: function module, T-junction module, and co-flow module. The function module can be replaced by (1) Single-inlet module, (2) Pneumatic Control Unit (PCU) module and (3) Dual-inlet module. Different modules can be easily assembled for different double emulsion production. By using the PCU module, double emulsions with different number of inner droplets have been successfully produced without complicated operation of flow rates of different phases. By using single and dual inlet module, various double emulsions with different number of encapsulated droplets or encapsulated droplets with different compositions have been successfully produced, respectively.

  10. Infrared Spectroscopy of Bilberry Extract Water-in-Oil Emulsions: Sensing the Water-Oil Interface

    Directory of Open Access Journals (Sweden)

    Johannes Kiefer

    2016-04-01

    Full Text Available Water-in-oil (w/o emulsions are of great interest in many areas of the life sciences, including food technology, bioprocess engineering, and pharmaceuticals. Such emulsions are complex multi-component systems and the molecular mechanisms which lead to a stable emulsion are yet to be fully understood. In this work, attenuated total reflection (ATR infrared (IR spectroscopy is applied to a series of w/o emulsions of an aqueous anthocyanin-rich bilberry extract dispersed in a medium chain triglyceride (MCT oil phase. The content of the emulsifier polyglycerin-polyricinoleat (PGPR has been varied systematically in order to investigate whether or not its concentration has an impact on the molecular stabilization mechanisms. The molecular stabilization is accessed by a careful analysis of the IR spectrum, where changes in the vibrational frequencies and signal strengths indicate alterations of the molecular environment at the water/oil interface. The results suggest that adding emulsifier in excess of 1% by weight does not lead to an enhanced stabilization of the emulsion.

  11. Catalytic Emulsion Based on Janus Nanosheets for Ultra-Deep Desulfurization.

    Science.gov (United States)

    Xia, Lixin; Zhang, Hairan; Wei, Zhichao; Jiang, Yi; Zhang, Ling; Zhao, Jie; Zhang, Junhui; Dong, Li; Li, Erni; Ruhlmann, Laurent; Zhang, Qian

    2017-02-03

    Catalytic Janus nanosheets were synthesized by using an anion-exchange reaction between heteropolyacids (HPAs) and the modified ionic-liquid (IL) moieties of Janus nanosheets. Their morphology and surface properties were characterized by using SEM, energy-dispersive spectroscopy (EDS), FTIR spectroscopy, and X-ray photoelectron spectroscopy (XPS) studies. Because of their inherent Janus structure, the nanosheets exhibited good amphipathic character with ILs and oil to form a stable ILs-in-oil emulsion. Therefore, these Janus nanosheets can be used as both emulsifiers and catalysts to perform emulsive desulfurization. During this process, sulfur-containing compounds at the interface could be easily oxidized and efficiently removed from a model oil. Application of this Janus emulsion brings an efficient, useful, and green procedure to the desulfurization process. Compared with the desulfurization catalyzed by using HPAs in a conventional two-phase system, the sulfur removal of dibenzothiophene (DBT) achieved in a Janus emulsion system was improved from 68 to 97 % within 1.5 h. Moreover, this emulsion system could be demulsified easily by simple centrifugation to recover both the nanosheets and the ILs. Owing to the good structural stability of the Janus nanosheets, the sulfur removal efficiency of DBT could still reach 99.9 % after the catalytic nanosheets had been recycled at least six times. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Palm Olein Emulsion: a Novel Vehicle for Topical Drug Delivery of Betamethasone 17-Valerate.

    Science.gov (United States)

    Ahmad, Kausar; Win, Thazin; Jaffri, Juliana Md; Edueng, Khadijah; Taher, Muhammad

    2018-01-01

    This study aims to investigate the use of palm olein as the oil phase for betamethasone 17-valerate (BV) emulsions. The physicochemical properties of the formulations were characterized. In vitro drug release study was performed with the Hanson Vertical Diffusion Cell System; the samples were quantified with HPLC and the results were compared with commercial products. Optimized emulsion formulations were subjected to stability studies for 3 months at temperatures of 4, 25, and 40°C; the betamethasone 17-valerate content was analyzed using HPLC. The formulations produced mean particle size of 2-4 μm, viscosities of 50-250 mPa.s, and zeta potential between -45 and -68 mV. The rheological analyses showed that the emulsions exhibited pseudoplastic and viscoelastic behavior. The in vitro release of BV from palm olein emulsion through cellulose acetate was 4.5 times higher than that of commercial products and more BV molecules deposited in rat skin. Less than 4% of the drug was degraded in the formulations during the 3-month period when they were subjected to the three different temperatures. These findings indicate that palm olein-in-water emulsion can be an alternative vehicle for topical drug delivery system with superior permeability.

  13. Rheology and microstructure of gluten and soya-based o/w emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Bengoechea, Carlos; Cordobes, Felipe; Guerrero, Antonio [Universidad de Sevilla, Departamento de Ingenieria Quimica, Sevilla (Spain)

    2006-10-15

    Highly concentrated oil-in-water (o/w) emulsion stabilised by means of gluten and soya protein isolate (SPI) at low pH have been characterized by means of linear dynamic viscoelasticity and droplet size distribution analysis (DSD). The microstructure of these emulsions has been characterized at a colloidal level by using confocal laser scanning microscopy (CLSM) and light microscopy (LM). These emulsions always exhibited a behaviour characteristic of highly flocculated emulsions with a mechanical spectrum showing a well-developed plateau region. DSD results generally showed log normal bimodal profiles. Microstructure images revealed occurrence of a close packing of droplets with a broad distribution of sizes participating in the formation of a three dimensional flocculated network. The Mason model of elasticity of compressed emulsions has been used to correlate viscoelastic and microstructural parameters giving adequate fitting but underestimating the elastic properties obtained for the highest concentration of gluten. These deviations may be explained in terms of an enhancement of the elastic network formed in the aqueous phase in which the glutenin fraction must play an important role. (orig.)

  14. Yeasts and bacterial biosurfactants as demulsifiers for petroleum derivative in seawater emulsions.

    Science.gov (United States)

    Rocha E Silva, Fernanda Cristina P; Roque, Bruno Augusto C; Rocha E Silva, Nathalia Maria P; Rufino, Raquel D; Luna, Juliana M; Santos, Valdemir A; Banat, Ibrahim M; Sarubbo, Leonie A

    2017-11-15

    Oil sludge or waste generated in transport, storage or refining forms highly stable mixtures due to the presence and additives with surfactant properties and water forming complex emulsions. Thus, demulsification is necessary to separate this residual oil from the aqueous phase for oil processing and water treatment/disposal. Most used chemical demulsifiers, although effective, are environmental contaminants and do not meet the desired levels of biodegradation. We investigated the application of microbial biosurfactants as potential natural demulsifiers of petroleum derivatives in water emulsions. Biosurfactants crude extracts, produced by yeasts (Candida guilliermondii, Candida lipolytica and Candida sphaerica) and bacteria (Pseudomonas aeruginosa, Pseudomonas cepacia and Bacillus sp.) grown in industrial residues, were tested for demulsification capacity in their crude and pure forms. The best results obtained were for bacterial biosurfactants, which were able to recover about 65% of the seawater emulsified with motor oil compared to 35-40% only for yeasts products. Biosurfactants were also tested with oil-in-water (O/W) and water-in-oil (W/O) kerosene model emulsions. No relationship between interfacial tension, cell hydrophobicity and demulsification ratios was observed with all the biosurfactants tested. Microscopic illustrations of the emulsions in the presence of the biosurfactants showed the aspects of the emulsion and demulsification process. The results obtained demonstrate the potential of these agents as demulsifiers in marine environments.

  15. Tri-fuel (diesel-biodiesel-ethanol) emulsion characterization, stability and the corrosion effect

    Science.gov (United States)

    Low, M. H.; Mukhtar, N. A. M.; Yohaness Hagos, Ftwi; Noor, M. M.

    2017-10-01

    This paper presents the result of experimenting emulsified tri-fuel in term of stability, physico-chemical properties and corrosion effect on three common metals. The results were interpreted in terms of the impact of five minutes emulsification approach. Tri-fuel emulsions were varied in proportion ratio consist of biodiesel; 0%, 5%, 10%, and ethanol; 5%, 10%, 15%. Fuel characterization includes density, calorific value, flash point, and kinematic viscosity. Flash point of tri-fuel emulsion came with range catalog. Calorific value of tri-fuel emulsion appeared in declining pattern as more ethanol and biodiesel were added. Biodiesel promoted flow resistance while ethanol with opposite effect. 15% ethanol content in tri-fuel emulsion separated faster than 10% ethanol content but ethanol content with 5% yield no phase separation at all. Close cap under static immersion with various ratio of tri-fuel emulsions for over a month, corrosiveness attack was detected via weight loss technique on aluminum, stainless steel and mild steel.

  16. Emulsions stabilized by precipitates of zirconium and tributyl phosphate degradation products

    International Nuclear Information System (INIS)

    Sugai, H.; Munakata, K.; Miyachi, S.; Yasu, S.

    1992-01-01

    In the Purex process, a solvent extraction method of nuclear fuel reprocessing, a stable emulsion called crud forms at the interface between the oil and water phases. This paper reports that crud is an emulsion stabilized by finely dispersed solids. Insoluble residues and precipitates of zirconium and radiation-degraded products of tributyl phosphate (TBP) are key materials in crud formation. Cruds formed by precipitates of zirconium and TBP degradation products, such as di-n-butyl phosphate (HDBP), mono-n-butyl phosphate (H 2 MBP), and phosphoric acid (H 3 PO 4 ) are studied. Experimental results show that the precipitate of zirconium and HDBP is not effective in stabilizing emulsions. However, the refractory complex of zirconium and H 3 PO 4 is an important material for stabilizing an oil-in-water emulsion in a solution with or without uranium. Moreover, it is shown that the complex of zirconium and H 2 MBP has a significant role in stabilizing a water-in-oil emulsion, especially when uranium is also present

  17. Phenolic residues in spruce galactoglucomannans improve stabilization of oil-in-water emulsions.

    Science.gov (United States)

    Lehtonen, M; Merinen, M; Kilpeläinen, P O; Xu, C; Willför, S M; Mikkonen, K S

    2018-02-15

    Amphiphilic character of surfactants drives them at the interface of dispersed systems, such as emulsions. Hemicellulose-rich wood extracts contain assemblies (lignin-carbohydrate complexes, LCC) with natural amphiphilicity, which is expected to depend on their chemical composition resulting from the isolation method. Lignin-derived phenolic residues associated with hemicelluloses are hypothesized to contribute to emulsions' interfacial properties and stability. We investigated the role of phenolic residues in spruce hemicellulose extracts in the stabilization of oil-in-water emulsions by physical and chemical approach. Distribution and changes occurring in the phenolic residues at the droplet interface and in the continuous phase were studied during an accelerated storage test. Meanwhile, the physical stability and lipid oxidation in emulsions were monitored. Naturally associated lignin residues in GGM act as vehicles for anchoring these hemicelluloses into the oil droplet interface and further enable superior stabilization of emulsions. By adjusting the isolation method of GGM regarding their phenolic profile, their functionalities, especially interfacial behavior, can be altered. Retaining the native interactions of GGM and phenolic residues is suggested for efficient physical stabilization and extended protection against lipid oxidation. The results can be widely applied as guidelines in tailoring natural or synthetic amphiphilic compounds for interfacial stabilization. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Effects of Propylene Glycol Alginate and Sucrose Esters on the Physicochemical Properties of Modified Starch-Stabilized Beverage Emulsions

    Directory of Open Access Journals (Sweden)

    Kok Whye Cheong

    2014-06-01

    Full Text Available This study was conducted to investigate the effect of main emulsion components namely, modified starch, propylene glycol alginate (PGA, sucrose laurate and sucrose stearate on creaming index, cloudiness, average droplet size and conductivity of soursop beverage emulsions. Generally, the use of different emulsifiers or a mixture of emulsifiers has a significant (p < 0.05 effect on the response variables studied. The addition of PGA had a significant (p < 0.05 effect on the creaming index at 55 °C, while PGA-stabilized (PGA1 emulsions showed low creaming stability at both 25 °C and 55 °C. Conversely, the utilization of PGA either as a mixture or sole emulsifier, showed significantly (p < 0.05 higher cloudiness, as larger average droplet size will affect the refractive index of the oil and aqueous phases. Additionally, the cloudiness was directly proportional to the mean droplet size of the dispersed phase. The inclusion of PGA into the formulation could have disrupted the properties of the interfacial film, thus resulting in larger droplet size. While unadsorbed ionized PGA could have contributed to higher conductivity of emulsions prepared at low pH. Generally, emulsions prepared using sucrose monoesters or as a mixture with modified starch emulsions have significantly (p < 0.05 lower creaming index and conductivity values, but higher cloudiness and average droplet size.

  19. Nonaqueous Dispersion Formed by an Emulsion Solvent Evaporation Method Using Block-Random Copolymer Surfactant Synthesized by RAFT Polymerization.

    Science.gov (United States)

    Ezaki, Naofumi; Watanabe, Yoshifumi; Mori, Hideharu

    2015-10-27

    As surfactants for preparation of nonaqueous microcapsule dispersions by the emulsion solvent evaporation method, three copolymers composed of stearyl methacrylate (SMA) and glycidyl methacrylate (GMA) with different monomer sequences (i.e., random, block, and block-random) were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. Despite having the same comonomer composition, the copolymers exhibited different functionality as surfactants for creating emulsions with respective dispersed and continuous phases consisting of methanol and isoparaffin solvent. The optimal monomer sequence for the surfactant was determined based on the droplet sizes and the stabilities of the emulsions created using these copolymers. The block-random copolymer led to an emulsion with better stability than obtained using the random copolymer and a smaller droplet size than achieved with the block copolymer. Modification of the epoxy group of the GMA unit by diethanolamine (DEA) further decreased the droplet size, leading to higher stability of the emulsion. The DEA-modified block-random copolymer gave rise to nonaqueous microcapsule dispersions after evaporation of methanol from the emulsions containing colored dyes in their dispersed phases. These dispersions exhibited high stability, and the particle sizes were small enough for application to the inkjet printing process.

  20. Effect of fat type and heat treatment on the microstructure of meat emulsions

    DEFF Research Database (Denmark)

    Miklos, Rikke; Lametsch, René; Nielsen, Mikkel Schou

    2013-01-01

    In comminuted meat products the gel-forming abilities of the myofibrillar proteins are of major importance. In meat emulsions fat will be present in globules which are stabilized by a membrane coating made of salt-soluble proteins. These discontinuous fat particles act as fillers or co......-polymers and stabilize the protein network. Differences in the physicochemical properties of saturated and unsaturated lipids affect the distribution of fat and thereby the functionality and quality of the final product. The objectives were to study the effects of lipid type and heat treatment on changes...... in microstructure of meat emulsions by use of a novel quantitative application of absorption- and phase-contrast tomography. The non-invasive technique offered the possibility to study the same sample in both raw and cooked condition. The samples were raw and heat treated meat emulsions (10% protein, 25% fat, 60...

  1. Lycopene in Beverage Emulsions: Optimizing Formulation Design and Processing Effects for Enhanced Delivery

    Directory of Open Access Journals (Sweden)

    Erika Meroni

    2018-02-01

    Full Text Available Lycopene is a desired ingredient in food formulations, yet its beneficial effects on human health remain largely underexploited due to its poor chemical stability and bioavailability. Oil-in-water emulsions may offer multiple advantages for the incorporation and delivery of this carotenoid species. Engineering and processing aspects for the development of emulsion-based delivery systems are of paramount importance for maintaining the structural integrity of lycopene. The selection of emulsifiers, pH, temperature, oil phase, particle size, homogenization conditions and presence of other antioxidants are major determinants for enhancing lycopene stability and delivery from a food emulsion. Process and formulation optimization of the delivery system is product-specific and should be tailored accordingly. Further research is required to better understand the underlying mechanisms of lycopene absorption by the human digestive system.

  2. Modeling and simulation of milk emulsion drying in spray dryers

    Directory of Open Access Journals (Sweden)

    V. S. Birchal

    2005-06-01

    Full Text Available This work aims at modeling and simulating the drying of whole milk emulsion in spray dryers. Drops and particles make up the discrete phase and are distributed into temporal compartments following their residence time in the dryer. Air is the continuous and well-mixed phase. Mass and energy balances are developed for each phase, taking into account their interactions. Constitutive equations for describing the drop swelling and drying mechanisms as well as the heat and mass transfer between particles and hot air are proposed and analyzed. A set of algebraic-differential equations is obtained and solved by specific numerical codes. Results from experiments carried out in a pilot spray dryer are used to validate the model developed and the numerical algorithm. Comparing the simulated and experimental data, it is shown that the model predicts well the individual drop-particle history inside the dryer as well as the overall outlet air-particle temperature and humidity.

  3. Cosmic-ray work with emulsions in the 1940s and 1950s

    International Nuclear Information System (INIS)

    Perkins, D.H.

    1989-01-01

    This chapter considers technical advances made in the 1940s and 1950s in the production of photographic emulsions for use in detecting and studying cosmic rays. The discovery, of the pion predicted theoretically by Yukawa in 1947 is described, and the dependance of its discovery on the new sensitive emulsions noted. The paper also charts work by physicists in a number of countries on kaons, the other intermediate mass particles discovered at this time. Later technical advances included thicker emulsions (up to 1,000 μm) and very large polyethylene balloons to take experimental apparatus up into the high cosmic-ray intensity stratosphere. Many of the balloon experiments were international collaborations. (UK)

  4. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Venezuela

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Venezuela. The IUREP Orientation Phase mission to Venezuela estimates that the Speculative Resources of that country fall within the range 2,000 to 42,000 tonnes uranium.- The majority of this potential is expected to be located in the Precambrian crystalline and sedimentary rocks of the Guayana Shield. Other potentially favorable geologic environments include Cretaceous phosphorite beds, continental sandstone and granitic rocks. The mission recommends that approximately US $18 million be spent on exploration in Venezuela over the next five years. The majority of this expenditure would be for surface surveys utilizing geologic studies, radiometric and geochemical surveys and some drilling for geologic information. Additional drilling would be required later to substantiate preliminary findings. (author)

  5. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Uganda

    International Nuclear Information System (INIS)

    1985-01-01

    A full report has been compiled describing the findings of the International Uranium Resources Evaluation Project (IUREP) Orientation Phase Mission to Uganda. The Mission suggest that the speculative uranium resources of the country could be within the very wide range of 0 to 105 000 tonnes of uranium metal. The Mission finds that most of these speculative resources are related to Proterozoic unconformities and to Cenozoic sandstones of the Western Rift Valley. Some potential is also associated with Post-tectonic granites. The Mission recommends to rehabilitate the Geological Survey of Uganda in order to enable it to conduct and support a uranium exploration programme for unconformity related and for standstone hosted uranium deposits. Recommended exploration methods encompass geological mapping and compilation, an airborne gamma-ray spectrometer survey north of 1 deg. North latitude, stream sediment sampling, and ground scintillometric surveys in favourable areas. Follow up work should include VLF-EM surveys, emanometry and drilling. (author)

  6. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Burundi

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Burundi. The IUREP Orientation Phase Mission to Burundi estimates that the Speculative Resources of that country fall within the range of 300 to more than 4 100 tonnes of uranium. The potential is rather evenly distributed throughout the Proterozoic of Burundi in various geological environments (unconformity, hydrothermal, fault controlled, etc.). The mission recommends that over a period of five years U.S. $ 3 to 4.5 million be spent on exploration in Burundi, with even spending on the various exploration techniques as e.g. prospecting, drilling trenching, geophysical surveys, analyses, etc. (author)

  7. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Bolivia

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Bolivia. The IUREP Orientation Phase mission to Bolivia estimates that the Speculative Uranium Resources of that country fall within the range of 100 to 107 500 tonnes uranium. The majority of this potential is expected to be located in the Precambrian crystalline and sedimentary rocks of the southwestern part of the Central Brazilian Shield. Other potentially favourable geologic environments include Palaeozoic two mica granites and their metasedimentary hosts, Mesozoic granites and granodiorites as well as the intruded formations and finally Tertiary acid to intermediate volcanics. The mission recommends that approximately US$ 13 million be spent on exploration in Bolivia over a five-year period. The majority of this expenditure would be for airborne and surface exploration utilising geologic, magnetometric, radiometric, and geochemical methods and some pitting, trenching, tunneling and drilling to further evaluate the discovered occurrences. (author)

  8. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Cameroon

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Cameroon. The IUREP Orientation Phase Mission to Cameroon estimates the Speculative Resources of that country to be in the order of 10 000 tonnes uranium for syenite-associated U-deposits in southern Cameroon, and in the order of 5 000 tonnes uranium for uranium deposits associated with albitized and desilicified late tectonic Panafrican granites (episyenite) and Paleozoic volcanics in northern Cameroon. No specific tonnage is given for Francevillian equivalents (DJA-Series) and for Mesozoic and Cenozoic sedimentary basins, which are thought to hold limited potential for sandstone hosted uranium. However the Douala basin, consisting of mixed marine and continental sequences merits some attention. No specific budget and programme for uranium exploration are proposed for Cameroon. Instead specific recommendations concerning specific potential environments and general recommendation concerning the methodology of exploration are made. (author)

  9. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Madagascar

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been made public which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Madagascar. The IUREP Orientation Phase Mission to Madagascar estimates the Speculative Resources of that country to be within the wide range of 4 000 to 38 000 tonnes uranium. Such resources could lie in areas with known occurrences (uranothorianite, Ft. Dauphin up to 5 000 t U, i.e. 'pegmatoids'; uranocircite, Antsirabe up to 3 000 t U in Neogene sediments; carnotiteautonite, Karoo area up to 30 000 t U in sandstones and in areas with as yet untested environments (e.g. related to unconformities and calcretes). Modifications to existing uranium exploration programmes are suggested and policy alternatives reviewed. No specific budget is proposed. (author)

  10. IFMIF-KEP. International fusion materials irradiation facility key element technology phase report

    International Nuclear Information System (INIS)

    2003-03-01

    The International Fusion Materials Irradiation Facility (IFMIF) is an accelerator-based D-Li neutron source designed to produce an intense neutron field that will simulate the neutron environment of a D-T fusion reactor. IFMIF will provide a neutron flux equivalent to 2 MW/m 2 , 20 dpa/y in Fe, in a volume of 500 cm 3 and will be used in the development and qualification of materials for fusion systems. The design activities of IFMIF are performed under an IEA collaboration which began in 1995. In 2000, a three-year Key Element Technology Phase (KEP) of IFMIF was undertaken to reduce the key technology risk factors. This KEP report describes the results of the three-year KEP activities in the major project areas of accelerator, target, test facilities and design integration. (author)

  11. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Rwanda

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Rwanda. The IUREP Orientation Phase Mission to Rwanda estimates that the Speculative Resources of that country fall within the range of 500 to 5 000 tonnes of uranium. The majority of this potential is expected to be located in the Precambrian Ruzizian, especially in conjunction with tectonized pegmatoidal remobilizations of metamorphic sediments of western Rwanda. Other favourable geological environments include lamprophyric dikes and post tectonic granites of central Rwanda. The Mission recommends that over a period of five years approximately US$4.2 million be spent on exploration in Rwanda. The majority of this would be spent on airborne and ground geophysical surveys ($1.5 million) and exploration drilling ($1 million). Prospecting, trenching and tunneling and analytical work would require the remainder of the $4.2 million ($1.7 million). (author)

  12. IFMIF-KEP. International fusion materials irradiation facility key element technology phase report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-03-01

    The International Fusion Materials Irradiation Facility (IFMIF) is an accelerator-based D-Li neutron source designed to produce an intense neutron field that will simulate the neutron environment of a D-T fusion reactor. IFMIF will provide a neutron flux equivalent to 2 MW/m{sup 2}, 20 dpa/y in Fe, in a volume of 500 cm{sup 3} and will be used in the development and qualification of materials for fusion systems. The design activities of IFMIF are performed under an IEA collaboration which began in 1995. In 2000, a three-year Key Element Technology Phase (KEP) of IFMIF was undertaken to reduce the key technology risk factors. This KEP report describes the results of the three-year KEP activities in the major project areas of accelerator, target, test facilities and design integration. (author)

  13. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Peru

    International Nuclear Information System (INIS)

    1984-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (TUREP) Mission to Peru. The IUREP Orientation Phase Mission to Peru estimates that the Speculative Resources of that country fall within the range of 6 000 to 11 000 tonnes uranium. The majority of this potential is expected to be located in Late Tertiary ignimbrites and associated sediments in the high Andes of southern Peru. Other favourable geological environments include calcretes, developed from Tertiary volcanogenic sources over the Precambrian in the Pacific Coastal desert in southern Peru, and Hercynian subvolcanic granites in the eastern Cordillera of southern Peru. The Mission recommends that over a period of five years approximately U.S. $10 million be spent on exploration in Peru. The majority of this would be spent on drilling ($5 million) and tunnelling ($2 million) with an additional $3 million on surface and airborne radiometric surveys. (author)

  14. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Ghana

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) Mission to Ghana. The IUREP Orientation Phase Mission to Ghana estimates that the Speculative Resources of that country fall within the range of 15 000 to 40 000 tonnes of uranium. The majority of this potential is expected to be located in the Proterozoic Panafrican Mobile Belt (up to 17 000 tonnes uranium) and the Paleozoic Obosum Beds of the Voltaian basin (up to 15 000 tonnes uranium), the remainder being associated with various other geological environments. The mission recommends that over a period of three (3) years approximately U.S. $5 million) would be spent on exploration in Ghana. A major part of this (U.S $2 million) would be spent on an airborne spectrometer survey over the Voltaian basin (Obosum beds), much of the remainder being spent on ground surveys, trenching and percussion drilling. (author)

  15. Palm oil anionic surfactants based emulsion breaker (Case study of emulsions breaker at Semanggi Field production wells)

    Science.gov (United States)

    Muhpidah; Hambali, E.; Suryani, A.; Kartika, I. A.

    2017-05-01

    The presence of emulsion in oil production process is undesirable. The emulsion will increase the production costs, transportation and costs related to emulsion separation process between water and oil. The development of palm oil-based surfactant as an emulsion breaker needs to be conducted given the availability of abundant raw materials in Indonesia and as an alternative to petroleum-based surfactant. The purpose of this study is to produce palm oil-based emulsion breaker, assessing the effect of additive application to the emulsion breaker and analyze the performance of the emulsion breaker. This research was conducted by formulating palm oil anionic surfactant in water formation with the addition of co-surfactant additive and co-solvent. Palm oil anionic surfactant-based emulsion breaker with 0.5% concentration in water can reduce 50% of emulsions with the interfacial tension (IFT) of 2.33x10-2 dyne/cm. The addition of co-solvent (toluene: xylene) is able to remove the emulsion formed with a lower IFT namely 10-3 dyne / cm. The resulting emulsion breaker is capable to remove the emulsion between water and oil. The performance test of emulsion breaker show that the emulsion is able to maintain its performance at reservoir temperature with no indicate of plugging and the value generated incremental oil recovery values is 13%.

  16. Validation of Spectra and Phase in Sub-1 cm-1 Resolution Sum-Frequency Generation Vibrational Spectroscopy through Internal Heterodyne Phase-Resolved Measurement

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Li; Chen, Shunli; Wang, Hongfei

    2016-03-03

    Reliably determination of the spectral features and their phases in sum-frequency generation vibrational spectroscopy (SFG-VS) for surfaces with closely overlapping peaks has been a standing issue. Here we present two approaches towards resolving such issue. The first utilizes the high resolution and accurate lineshape from the recently developed sub-wavenumber high resolution broadband SFG-VS (HR-BB-SFG-VS), from which the detail spectral parameters, including relative spectral phases, of overlapping peaks can be determined through reliable spectral fitting. These results are further validated by using the second method that utilizes the azimuthal angle phase dependence of the z-cut α-quartz crystal, a common phase standard, through the spectral interference between the SFG fields of the quartz surface, as the internal phase reference, and the adsorbed molecular layer. Even though this approach is limited to molecular layers that can be transferred or deposited onto the quartz surface, it is simple and straightforward, as it requires only an internal phase standard with a single measurement that is free of phase drifts. More importantly, it provides unambiguous SFG spectral phase information of such surfaces. Using this method, the absolute phase of the molecular susceptibility tensors of the CH3, CH2 and chiral C-H groups in different Langmuir-Blodgett (LB) molecular monolayers and drop-cast peptide films are determined. These two approaches are fully consistent with and complement to each other, making both easily applicable tools in SFG-VS studies. More importantly, as the HR-BB-SFG-VS technique can be easily applied to various surfaces and interfaces, such validation of the spectral and phase information from HR-BB-SFG-VS measurement demonstrates it as one most promising tool for interrogating the detailed structure and interactions of complex molecular interfaces.

  17. The comparison of oxidative thermokinetics between emulsion and microemulsion diesel fuel

    International Nuclear Information System (INIS)

    Leng, Lijian; Yuan, Xingzhong; Zeng, Guangming; Wang, Hou; Huang, Huajun; Chen, Xiaohong

    2015-01-01

    Highlights: • Microemulsion fuel (>90 days) was much more stable than emulsion (≈2 days). • Microemulsification decreased activation energy of the fuel system by 5 kJ mol −1 . • Emulsification increased activation energy of the fuel system by 15 kJ mol −1 . • Microemulsification was more competitive for fuel upgrading than emulsification. - Abstract: Water fuel emulsion has been widely studied with the advantages of saving energy, enhancing engine torque, improving engine performance, and reducing the pollutant emissions. However, it has unfavorable disadvantages such as phase separation and long ignition delay. Water fuel microemulsion with rhamnolipid as the surfactant was formed in this study and characterized in comparison to water fuel emulsion. Water fuel microemulsion was thermodynamically stable without phase separation after 90 days vs. the milky-white emulsion fuel, separated within 2 days. In the thermogravimetric analysis, the TG and DTG curves were shifted to higher temperatures as the increment of heating rate. However, the shift for emulsion at 40 K min −1 was inconspicuous, which implies the reduction in heat transfer, mass transfer, and vaporization rates and further the lengthened ignition delay upon combustion in diesel engine. The activation energies (E a ) predicted by Ozawa–Flynn–Wall (OFW), Kissinger–Akhira–Sunose (KAS), and Starink’s methods indicate that the formation of microemulsion could decrease the activation energy of the fuel by about 5 kJ mol −1 , while the formation of emulsion would increase by 15 kJ mol −1 . The lower activation energy of microemulsion fuel is an indication of easy ignition or shortened ignition delay. Thus, microemulsification may be a more competitive technique for fuel upgrading compared to emulsification

  18. Improved physical stability and injectability of non-aqueous in situ PLGA microparticle forming emulsions.

    Science.gov (United States)

    Voigt, M; Koerber, M; Bodmeier, R

    2012-09-15

    The goal of this study was to obtain physically stable non-aqueous in situ forming microparticle (ISM) emulsions capable of forming biodegradable microparticles upon injection. ISM emulsions consist of a biocompatible organic PLGA solution dispersed in a continuous oil phase prepared in a two-syringe/connector system prior to administration. A variety of parenteral approved excipients were tested for a stability-enhancing effect and possible stabilization mechanisms evaluated. Glycerol monostearate (GMS) showed superior stabilizing potential prolonging the emulsion stability from a few minutes to more than 12h. Flow behavior analysis, differential scanning calorimetry, polarized light- and Cryo-electron microscopy revealed, that the stabilization was caused by an immediate, more than 5-fold viscosity increase in the continuous phase after emulsification and by a stabilized interface through a liquid crystalline GMS layer around the polymer solution droplets. Despite the viscosity increase the injectability of the stabilized ISM emulsion was improved by about 30% compared to the corresponding highly viscous PLGA solution (in situ implant) due to a pronounced shear thinning of the GMS containing oil phase. The injectability improvement allows a faster administration or enables the use of thinner needles and hence reduced patient discomfort. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Development of cetyl dimethicone based water-in-oil emulsion containing botanicals: Physical characteristics and stability.

    Science.gov (United States)

    Waqas, Muhammad Khurram; Akhtar, Naveed; Shah, Pervaiz Akhtar; Danish, Muhammad Zeeshan; Shah, Arshad Ali; Braga, Valdir de Andrade; Khan, Barkat Ali

    2016-01-01

    The aim of current research was to develop a water-in-oil emulsion containing grape seed extract for application in cosmeceuticals. Finally grinded dried grape seeds powder was extracted with hydro alcoholic mixture. Emulsions consisting of different concentrations of cetyl dimethicone (Abile EM90), the nonionic emulsifier, liquid paraffin as oily phase and water as aqueous phase were developed. Color, odor, pH, viscosity, liquefaction, phase separation, centrifugation and thermal stability of the formulated emulsions were observed at various storage temperatures i.e. 8±0.5°C, 25±0.5°C, 40±0.5°C and 40°C±0.5°C with 70% RH. The stable formulation consist of 16% mineral oil, 4% of ABIL EM 90(®), 4% grape seeds extract, 1% rose oil and 75% distilled water. All the results derived from this study showed good stability over the three months study period which indicates w/o emulsion can be used as carrier of 4% grape seeds extract to enhance desired effects when applied topically.

  20. Study of internal transport barriers in the initial phase of Ohmic discharges in TUMAN-3M

    International Nuclear Information System (INIS)

    Askinazi, L G; Bulanin, V V; Vildjunas, M I; Golant, V E; Gorokhov, M V; Kornev, V A; Krikunov, S V; Lebedev, S V; Petrov, A V; Rozhdestvensky, V V; Tukachinsky, A S; Zhubr, N A

    2004-01-01

    A regime with electron heat confinement improvement was recently found in the initial phase of discharges in the TUMAN-3M tokamak. An internal transport barrier (ITB) formation in this regime was confirmed by Thomson scattering measurements and by transport modelling. Two possible reasons for the ITB formation are discussed in the paper: by reduction of turbulent transport in the presence of low magnetic shear or by plasma sheared rotation. It is demonstrated that low magnetic shear formation is possible in the current ramp-up phase of the Ohmic discharge. The low magnetic shear does not seem to be the only reason for the transport reduction. Results of Doppler reflectometry measurements of poloidal rotation of density fluctuations are presented. It is found that core confinement improvement correlates with the appearance of sheared rotation of the density fluctuations and with a burst of the MHD activity. The ITB formation in the regime seems to be a result of a combined action of reduced magnetic shear and plasma sheared rotation

  1. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Morocco

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published on the findings of the mission to Morocco under the International Uranium Resources Evaluation Project (IUREP) Orientation Phase. The IUREP Orientation Phase Mission estimates that the speculative resources of Morocco range from 70 000 to 180 000 tonnes of uranium, half of which could be expected to occur in the Northern Provinces, which are relatively well explored, and the other half in the little explored Southern Provinces. In the north, speculative resources are fairly evenly distributed among the various types of deposit, in particular vein deposits (intragranitic and contact) linked with Hercynian and Precambrian blocks, the sandstone type deposits linked with Mesozoic strata and the volcanogenic deposits, especially of Precambrian age. The potential for large high-grade deposits, especially for those linked with unconformities and linear albitites, has been little investigated in Morocco and is chiefly thought to lie in the Precambrian in the Anti-Atlas and Southern Provinces. Here, the presence of acid volcanic rock reinforces the uranium potential, and there is also some potential for calcrete-related deposits. Phosphate-related uranium, to be recovered shortly, constitutes by far the largest reserves in Morocco, estimated at about 7 million tonnes of recoverable uranium. Recommendations have been made for further study of known occurrences and identification of new ones, such as unconformity and albitite-related deposits. (author) [fr

  2. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Morocco

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published on the findings of the mission to Morocco under the International Uranium Resources Evaluation Project (IUREP) Orientation Phase. The IUREP Orientation Phase Mission estimates that the speculative resources of Morocco range from 70 000 to 180 000 tonnes of uranium, half of which could be expected to occur in the Northern Provinces, which are relatively well explored, and the other half in the little explored Southern Provinces. In the north, speculative resources are fairly evenly distributed among the various types of deposit, in particular vein deposits (intragranitic and contact) linked with Hercynian and Precambrian blocks, the sandstone type deposits linked with Mesozoic strata and the volcanogenic deposits, especially of Precambrian age. The potential for large high-grade deposits, especially for those linked with unconformities and linear albitites, has been little investigated in Morocco and is chiefly thought to lie in the Precambrian in the Anti-Atlas and Southern Provinces. Here, the presence of acid volcanic rock reinforces the uranium potential, and there is also some potential for calcrete-related deposits. Phosphate-related uranium, to be recovered shortly, constitutes by far the largest reserves in Morocco, estimated at about 7 million tonnes of recoverable uranium. Recommendations have been made for further study of known occurrences and identification of new ones, such as unconformity and albitite-related deposits. (author)

  3. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Portugal

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Portugal. The IUREP Orientation Phase mission to Portugal estimates that the Speculative Resources of that country fall within the range 20,000 to 80,000 tonnes uranium. The majority of this potential is expected to be located in intergranitic vein deposits and in pre-Ordovician schists, but other favourable geological environments include episyenites and Meso-Cainozoic continental sediments. The mission recommends that approximately US$25 million be spent on exploration in Portugal over the next 10 years. The majority of this ($18 million) would be spent on drilling, with a further $7 million on surface surveys and airborne radiometric surveys. It is the opinion of the IUREP Orientation Phase Mission that the considerable funding required for the outlined programme would most suitably be realized by inviting national or foreign commercial organisations to participate in the exploration effort under a partnership or shared production arrangements. (author)

  4. Phased Array Noise Source Localization Measurements Made on a Williams International FJ44 Engine

    Science.gov (United States)

    Podboy, Gary G.; Horvath, Csaba

    2010-01-01

    A 48-microphone planar phased array system was used to acquire noise source localization data on a full-scale Williams International FJ44 turbofan engine. Data were acquired with the array at three different locations relative to the engine, two on the side and one in front of the engine. At the two side locations the planar microphone array was parallel to the engine centerline; at the front location the array was perpendicular to the engine centerline. At each of the three locations, data were acquired at eleven different engine operating conditions ranging from engine idle to maximum (take off) speed. Data obtained with the array off to the side of the engine were spatially filtered to separate the inlet and nozzle noise. Tones occurring in the inlet and nozzle spectra were traced to the low and high speed spools within the engine. The phased array data indicate that the Inflow Control Device (ICD) used during this test was not acoustically transparent; instead, some of the noise emanating from the inlet reflected off of the inlet lip of the ICD. This reflection is a source of error for far field noise measurements made during the test. The data also indicate that a total temperature rake in the inlet of the engine is a source of fan noise.

  5. IFMIF (International Fusion Materials Irradiation Facility) key element technology phase task description

    International Nuclear Information System (INIS)

    Ida, M.; Nakamura, H.; Sugimoto, M.; Yutani, T.; Takeuchi, H.

    2000-08-01

    In 2000, a 3 year Key Element technology Phase (KEP) of the International Fusion Materials Irradiation Facility (IFMIF) has been initiated to reduce the key technology risk factors needed to achieve continuous wave (CW) beam with the desired current and energy and to reach the corresponding power handling capabilities in the liquid lithium target system. In the KEP, the IFMIF team (EU, Japan, Russian Federation, US) will perform required tasks. The contents of the tasks are described in the task description sheet. As the KEP tasks, the IFMIF team have proposed 27 tasks for Test Facilities, 12 tasks for Target, 26 tasks for Accelerator and 18 tasks for Design Integration. The task description by RF is not yet available. The task items and task descriptions may be added or revised with the progress of KEP activities. These task description sheets have been compiled in this report. After 3 years KEP, the results of the KEP tasks will be reviewed. Following the KEP, 3 years Engineering Validation Phase (EVP) will continue for IFMIF construction. (author)

  6. Phase equilibria computations of multicomponent mixtures at specified internal energy and volume

    Science.gov (United States)

    Myint, Philip C.; Nichols, Albert L., III; Springer, H. Keo

    2017-06-01

    Hydrodynamic simulation codes for high-energy density science applications often use internal energy and volume as their working variables. As a result, the codes must determine the thermodynamic state that corresponds to the specified energy and volume by finding the global maximum in entropy. This task is referred to as the isoenergetic-isochoric flash. Solving it for multicomponent mixtures is difficult because one must find not only the temperature and pressure consistent with the energy and volume, but also the number of phases present and the composition of the phases. The few studies on isoenergetic-isochoric flash that currently exist all require the evaluation of many derivatives that can be tedious to implement. We present an alternative approach that is based on a derivative-free method: particle swarm optimization. The global entropy maximum is found by running several instances of particle swarm optimization over different sets of randomly selected points in the search space. For verification, we compare the predicted temperature and pressure to results from the related, but simpler problem of isothermal-isobaric flash. All of our examples involve the equation of state we have recently developed for multiphase mixtures of the energetic materials HMX, RDX, and TNT. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  7. Fundamental experiment on the problem of large, structured rooms with internal two-phase flow

    International Nuclear Information System (INIS)

    Geweke, M.

    1992-01-01

    A loss of coolant accident in a pressurized water reactor results in two phase flow in the upper plenum region. Steam will be generated from the fuel elements and will flow upwards into the upper plenum. Water drops will be entrained and transported by the steam and will be deentrained in the upper plenum. The deentrained water and the upflowing steam can lead to a condition defined as countercurrent flow limitation which tends to restrict the water downflow. The aim of this research project is to investigate the co- and countercurrent flow in the upper plenum region. The influence of the internals, which are installed in scale 1:1 and the outlet flow conditions into the hot leg is investigated. The establishing flow regime depends on the volumetric flow rates of gas and liquid and the area in the upper plenum, which is simulated by the arangement of the internals. An increasing gas flow rate causes flooding in the tie plate. A turbulent froth layer is established above the tie plate. A further increase in the gas flow rate causes flooding in the upper plenum. The experimental results are compared with well-known empirical correlations and with the experimental investigations from the UPTF. A suitable measurement technique is developed to measure the local and time-dependent liquid hold-up, the diameter and the velocity of the drops. (orig.) [de

  8. Ethylene Separation via Hydrate Formation in W/O Emulsions

    Directory of Open Access Journals (Sweden)

    Yong Pan

    2015-05-01

    Full Text Available An hybrid absorption-hydration method was adopted to recover C2H4 from C2H4/CH4 binary gas mixtures and the hydrate formation conditions of C2H4/CH4 mixtures was studied experimentally in diesel in water (w/o emulsions. Span 20 at a concentration of 1.0 wt% in the aqueous phase was added to form water in diesel emulsions before hydrate formation and then hydrate in diesel slurry was separated after hydrate formation. The influences of initial gas-liquid volume ratio (53–142, pressure (3.4–5.4 MPa, temperature (274.15–278.15 K, water cuts (10–30 vol%, and the mole fraction of C2H4 in feed gas (13.19–80.44 mol% upon the C2H4 separation efficiency were systematically investigated. The experimental results show that ethylene can be enriched in hydrate slurry phase with high separation factor (S and recovery ratio (R. Most hydrate formation finished in 20 min, after that, the hydrate formation rate became very slow. The conclusion is useful for determining the suitable operation conditions when adopting an absorption-hydration method to separate C2H4/CH4.

  9. The effect of butter grains on physical properties of butter-like emulsions.

    Science.gov (United States)

    Rønholt, Stine; Buldo, Patrizia; Mortensen, Kell; Andersen, Ulf; Knudsen, Jes C; Wiking, Lars

    2014-01-01

    Milk fat exists as globules in its natural state in milk. The potential of using globular fat to modulate the rheological properties and crystallization behavior in butter-like emulsions was studied in the present work. We conducted a comparative study of butter-like emulsions, with a fat phase consisting of 0, 10, 25, 50, or 100% anhydrous milk fat (AMF), the remaining fat being butter grains, and all samples containing 20% water, to obtain systematic variation in the ratio of globular fat. All emulsions were studied over 4wk of storage at 5°C. By combining small and large deformation rheology, we conducted a detailed characterization of the rheological behavior of butter-like emulsions. We applied differential scanning calorimetry to monitor thermal behavior, confocal laser scanning microscopy for microstructural analysis, and low-field pulsed nuclear magnetic resonance spectrometry to measure solid fat content. By combining these techniques, we determined that increasing the fraction of globular fat (by mixing with butter grains) decreases the hardness of butter-like emulsions up to an order of magnitude at d 1. However, no difference was observed in thermal behavior as a function of butter grain content, as all emulsions containing butter grains revealed 2 endothermal peaks corresponding to the high (32.7°C ± 0.6) and medium (14.6°C ± 0.1) melting fractions of fatty acids. In terms of microstructure, decreasing the amount of butter grains in the emulsions resulted in formation of a denser fat crystal network, corresponding to increased hardness. Moreover, microstructural analysis revealed that the presence of butter grains resulted in faster formation of a continuous fat crystal network compared with the 100% AMF sample, which was dominated by crystal clusters surrounded by liquid oil. During storage, hardness remained stable and no changes in thermal behavior were observed, despite an increase in solid fat content of up to 5%. After 28d of storage, we

  10. Oscillation of a rigid catenary riser due to the internal two-phase flow

    Energy Technology Data Exchange (ETDEWEB)

    Bordalo, Sergio N.; Morooka, Celso K.; Cavalcante, Cesar C.P. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Matt, Cyntia G.C.; Franciss, Ricardo [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    2008-07-01

    Production of petroleum reservoirs from deep and ultra-deep waters is of paramount importance in Brazil, and several researches are necessary to develop appropriated equipment and risers for those operational conditions. Risers are suspended pipes used to transport the petroleum fluids between the seabed and the floating production unit. The structural flexibility of riser's lines is conferred by its length when compared with the diameter, characterizing it as a slender body. The risers are submitted to large static and dynamic loads originated from its own weight, waves, currents, platform motions and the internal flow. These loadings may threaten, by fatigue, the structural integrity of the system, compromising its useful life, and so they must be considered in the riser's project. There is a large amount of knowledge in the literature about the effects of external loadings on these systems, but the effect of the internal flow remains vastly unexplored. The variation of the flow mass and momentum inside the riser causes a dynamic loading on this system, originating an oscillatory motion. Furthermore, the gas-liquid two-phase flow may assume several flow patterns (bubble, slug, intermittent or annular), each one possessing completely different characteristics. In this work, the influence of the internal flow on the oscillatory motion (whipping motion) of catenary risers is analyzed. To provide a better understanding of this physical phenomenon, a scaled apparatus was designed and built. The material used to manufacture the riser's model was a flexible silicone tube, and air and water were used to simulate the two-phase flow. The instrumentation used to measure the fluids flow rates and the sustaining force at the top of the model was installed in the apparatus. A video acquisition system was used to determine the displacements, and frequency spectrum, of color targets positioned throughout the model, under several flow conditions. The flow patterns

  11. Stability studies of cosmetic emulsions prepared from natural products such as wine, grape seed oil and mastic resin

    NARCIS (Netherlands)

    Glampedaki, P.; Dutschk, Victoria

    2014-01-01

    An attempt was made in this study to use diluted wine as the aqueous phase and grapeseed oil as the oil phase for the preparation of oil-in-water cosmetic emulsions. Two monovarietal wines of Hellenic origin were used in this study; a red one from Sangiovese grapes and a white one from Muscat of

  12. Developing novel one-step processes for obtaining food-grade O/W emulsions from pressurized fluid extracts: processes description, state of the art and perspectives

    Directory of Open Access Journals (Sweden)

    Diego Tresinari SANTOS

    2015-01-01

    Full Text Available AbstractIn this work, a novel on-line process for production of food-grade emulsions containing oily extracts, i.e. oil-in-water (O/W emulsions, in only one step is presented. This process has been called ESFE, Emulsions from Supercritical Fluid Extraction. With this process, emulsions containing supercritical fluid extracts can be obtained directly from plant materials. The aim in the conception of this process is to propose a new rapid way to obtain emulsions from supercritical fluid extracts. Nowadays the conventional emulsion formulation method is a two-step procedure, i.e. first supercritical fluid extraction for obtaining an extract; secondly emulsion formulation using another device. Other variation of the process was tested and successfully validated originating a new acronymed process: EPFE (Emulsions from Pressurized Fluid Extractions. Both processes exploit the supercritical CO2-essential oils miscibility, in addition, EPFE process exploits the emulsification properties of saponin-rich pressurized aqueous plant extracts. The feasibility of this latter process was demonstrated using Pfaffia glomerata roots as source of saponin-rich extract, water as extracting solvent and clove essential oil, directly extracted using supercritical CO2, as a model dispersed phase. In addition, examples of pressurized fluid-based coupled processes applied for adding value to food bioactive compounds developed in the past five years are reviewed.

  13. Evaluation of nano emulsion containing asphaltenes dispersant additive in dehydration of oil; Avaliacao de nanoemulsoes contendo aditivo dispersante de asfaltenos na desidratacao de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Priscila F. de; Rodrigues, Jessica S.; Mansur, Claudia R.E. [Universidade Federal do Rio de Janeiro/ Instituto de Macromoleculas/ Laboratorio de Macromoleculas e Coloides na Industria de Petroleo, Rio de Janeiro, RJ (Brazil)], e-mail: prisfrias@hotmail.com

    2011-07-01

    Due to the problem of the formation of emulsions type water-oil during oil production, new alternatives of the breakdown of these emulsions have been proposed over the years. Several polymers have been used to destabilize these emulsions and among them are those based on polyphenylene ether. The aim of this study was to develop nanoemulsions type oil / water, where an asphaltenes dispersant additive was dissolved in dispersed phase in order to evaluate them as a new alternative in the breakdown of oil emulsions. The nanoemulsions were prepared in the presence of surfactant based on polyoxide using a high pressure homogenizer (HPH). We obtained stable nanoemulsions for more than 30 days in the presence or absence of additive. These nanoemulsions were effective in water /oil phase separation, and the nanoemulsion containing the dispersant additive provided a faster separation of these phases. (author)

  14. Destabilization and Recuperability of Oil Used in the Formulation of Concentrated Emulsions and Cutting Fluids

    OpenAIRE

    Guimarães, A. P.; Maia, D. A. S.; Araújo, R. S.; Cavalcante Jr, C. L.; de Sant’Ana, H. B.

    2010-01-01

    Lubricants known as cutting fluids are used in the metal-mechanic industry with the function of cooling and lubricating the cutting zone. These lubricants normally have a water phase, an oil phase, emulsifying agents and additives. Once the operational capacity of these fluids has ceased, either due to biological deterioration or to overabundance of contaminants, the emulsions being used must be treated in order to adequate their effluents for discharge. This study aims to evaluate the destab...

  15. Vegetable oil based emulsions in milk

    Directory of Open Access Journals (Sweden)

    Veronika Mikulcová

    2014-07-01

    Full Text Available Milk and dairy products represent an important part of functional food in the market. Based on their positive health and nutritional benefits, they have gained popularity and their consumption as well as production is on the rise in the last few decades. As a result of this trend, milk-based products are being used for the delivery of bioactive food ingredients. This study is devoted to the formulation of stable emulsions containing grape seed oil dispersed with several emulsifiers (Tween 80, monocaprylin, and lecithin in milk. Photon correlation spectroscopy was used to evaluate the characteristics of the emulsions in terms of mean droplet size, droplet size distribution and polydispersity index. Emulsions were prepared using 2% and 5% w/w grape seed oil, and 3%, 5%, or 8% w/w emulsifier, and these were homogenized at two different rates of 1050 and 13400 rpm. Parameters influencing emulsion particle size and particle size distribution were identified, which included emulsifier type, its HLB value, oil type (virgin, refined, homogenization rate and the fat content in the milk. Homogenization at 13400 rpm for 10 min. produced fine emulsions with small mean particle sizes and monomodal distribution of droplets. Regarding emulsifier type, the smallest droplet sizes were obtained with formulations containing Tween 80 (250-315 nm, whereas lecithin primarily accounted for the monomodal particle size distributions.

  16. Application of superheated emulsions in neutron spectrometry

    International Nuclear Information System (INIS)

    Das, Mala; Abe, Masashi; Sawamura, Teruko; Roy, S.C; Chatterjee, B.K.; Roy, B.

    2003-01-01

    'Superheated emulsions' are known to detect energetic radiations. The use of superheated emulsion as neutron spectrometry needs monoenergetic neutrons for the calibration. Because of the limitation of the availability of monoenergetic neutrons, the present work deals with the alternative method to find out the temperature-threshold neutron energy relationship for superheated emulsions. R-114 (C2C12F4, b.p.3.77degC) is used as the superheated liquid to unfold the neutron energy spectrum generated at Pb target by 45 MeV electron LINAC. The normalized response of the emulsion with temperature is obtained as an integrated spectrum, the derivative of which generates neutron energy spectrum. It is noted that R114 detector is insensitive to gamma rays at low temperature and it is only at 70degC to low energy. The present study gives an approach to the application of superheated emulsions in neutron spectrometry in a complex radiation field of both gamma rays and neutrons of different energy. (T. Tanaka)

  17. Effect of bitumen emulsion on setting, strength, soundness and ...

    Indian Academy of Sciences (India)

    Addition of bitumen emulsion to the matrix has been found to improve strength and soundness of the product while decreasing the initial setting periods. Thus, bitumen emulsion as an admixture in magnesia cement is a moisture proofing and strengthening material.

  18. Sensory analysis of cosmetic powders: personal care ingredients and emulsions.

    Science.gov (United States)

    Moussour, M; Lavarde, M; Pensé-Lhéritier, A-M; Bouton, F

    2017-02-01

    The powders are ingredients increasingly used in the formulation of cosmetic products for the sensory qualities they give. The objective of this study was the development of a lexicon and a referential for sensory characterization of these pure raw materials as well as formulations which contain them. Eleven expert panellists from Ecole de biologie industrielle de Cergy (France) developed a lexicon and a referential based on 12 powders of different chemical natures. The selected attributes were then used for performing a quantitative descriptive profile of two powders and an emulsion containing or not one of these two powders. A lexicon has been established through a consensus approach of the panel. It contains seven attributes that allow the evaluation of the powders in four phases: the appearance, the pickup, the application and the after-feel. This lexicon contains definitions and assessment protocols and provides references products. The quantitative descriptive profile of two powders of the same chemical nature, but different in physical quality showed significant differences in sensory level between products. These same attributes used to evaluate an emulsion containing the powder or not allowed to prove the contribution of these raw materials on the sensory specificities of the emulsion. The lexicon developed in this study can be used for assessment of other powders but also to define the quantities necessary to put in the formulation to meet the sensory characteristics of these raw materials powder. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  19. Phase Holdups in A Three-Phase Fluidized Bed in the Presence of Coaxially Placed String of Spheres Internal

    Science.gov (United States)

    Rohini Kumar, P.; Ramesh, K. V.; Venkateswarlu, P.

    2017-08-01

    Experiments were conducted to investigate the effect of various pertinent dynamic and geometric variables on individual phase holdups in a three-phase fluidized bed in the presence of a string of spheres promoter. Bed porosity was determined from measured bed height. Gas holdup was calculated from pressure drop data. Liquid hold was obtained by subtracting the sum of gas and solids holdup from unity. An electrolyte belonging to ferri-ferro redox system has been used as liquid phase. Glass balls of different sizes were chosen as fluidizing solids and nitrogen was employed as gas phase. The data on gas holdup, liquid holdup and bed porosity were graphically analyzed and correlation equations were obtained.

  20. Microfluidic preparation and self diffusion PFG-NMR analysis of monodisperse water-in-oil-in-water double emulsions.

    Science.gov (United States)

    Hughes, Eric; Maan, Abid Aslam; Acquistapace, Simone; Burbidge, Adam; Johns, Michael L; Gunes, Deniz Z; Clausen, Pascal; Syrbe, Axel; Hugo, Julien; Schroen, Karin; Miralles, Vincent; Atkins, Tim; Gray, Richard; Homewood, Philip; Zick, Klaus

    2013-01-01

    Monodisperse water-in-oil-in-water (WOW) double emulsions have been prepared using microfluidic glass devices designed and built primarily from off the shelf components. The systems were easy to assemble and use. They were capable of producing double emulsions with an outer droplet size from 100 to 40 μm. Depending on how the devices were operated, double emulsions containing either single or multiple water droplets could be produced. Pulsed-field gradient self-diffusion NMR experiments have been performed on the monodisperse water-in-oil-in-water double emulsions to obtain information on the inner water droplet diameter and the distribution of the water in the different phases of the double emulsion. This has been achieved by applying regularization methods to the self-diffusion data. Using these methods the stability of the double emulsions to osmotic pressure imbalance has been followed by observing the change in the size of the inner water droplets over time. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Proteins, polysaccharides, and their complexes used as stabilizers for emulsions: alternatives to synthetic surfactants in the pharmaceutical field?

    Science.gov (United States)

    Bouyer, Eléonore; Mekhloufi, Ghozlene; Rosilio, Véronique; Grossiord, Jean-Louis; Agnely, Florence

    2012-10-15

    Emulsions are widely used in pharmaceutics for the encapsulation, solubilization, entrapment, and controlled delivery of active ingredients. In order to answer the increasing demand for clean label excipients, natural polymers can replace the potentially irritative synthetic surfactants used in emulsion formulation. Indeed, biopolymers are currently used in the food industry to stabilize emulsions, and they appear as promising candidates in the pharmaceutical field too. All proteins and some polysaccharides are able to adsorb at a globule surface, thus decreasing the interfacial tension and enhancing the interfacial elasticity. However, most polysaccharides stabilize emulsions simply by increasing the viscosity of the continuous phase. Proteins and polysaccharides may also be associated either through covalent bonding or electrostatic interactions. The combination of the properties of these biopolymers under appropriate conditions leads to increased emulsion stability. Alternative layers of oppositely charged biopolymers can also be formed around the globules to obtain multi-layered "membranes". These layers can provide electrostatic and steric stabilization thus improving thermal stability and resistance to external treatment. The novel biopolymer-stabilized emulsions have a great potential in the pharmaceutical field for encapsulation, controlled digestion, and targeted release although several challenging issues such as storage and bacteriological concerns still need to be addressed. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Structural study of micro-emulsions in an inversion domain. Highlighting a bi-continuous cubic structure

    International Nuclear Information System (INIS)

    Geyer d'Orth, Arnaud de

    1987-01-01

    This research thesis report the study of the structure of micro-emulsions in an inversion domain (domain of Winsor equilibriums) by using small angle neutron scattering. In this domain, the micro-emulsion keeps on passing from water-rich state (Winsor I domain) to an oil-rich state (Winsor II domain). In the intermediate domain (Winsor III domain), the micro-emulsion presents the peculiarity to be able to solubilise equal volumes of water and oil. The small angle neutron scattering technique allows highlighting the continuous passage from of an 'oil in water' droplet dispersion (Winsor I) to a 'water in oil' droplet dispersion (Winsor II) with an intermediate bi-continuous structure (Winsor III). The author shows that the micro-emulsion structure in the inversion domain is not random, but corresponds to a cubic structure. He also shows that the interface film of the Winsor III micro-emulsion forms a minimum surface. The author highlights the structure continuity between the Winsor III micro-emulsion and a cubic liquid crystal phase [fr

  3. Supralinearity and particle discrimination in nuclear emulsion

    International Nuclear Information System (INIS)

    Katz, R.; Larsson, L.; Pinkerton, F.E.; Benton, E.V.

    1977-01-01

    Nuclear emulsions may be desensitized in manufacture and/or may be so processed as to discriminate against small latent image sites; to yield supralinear sensitometric response after x-irradiation; and to discriminate against lightly ionizing radiations in favor of heavily ionizing particles. In a circumstance where one electron passing through an emulsion grain is unlikely to generate a latent image sufficiently large to yield a visible grain after development, some larger number of electrons is required, resulting in 'many-hit' statistics, supralinearity, and particle discrimination: for lightly ionizing particles are not likely to generate more than one delta-ray (secondary electron) in their passage through or near a grain. Since these properties are analogous to the response of many biological cells to ionizing radiations, such emulsion-developer combinations have the potential to mimic the response of biological systems to particulate radiations of different charge and speed. (author)

  4. Emulsion chamber experiments for the Space Station

    Science.gov (United States)

    Wilkes, R. J.

    Emulsion chambers offer several unique features for the study of ultrahigh-energy cosmic-ray interactions and spectra aboard a permanent manned Space Station. Emulsion-chamber experiments provide the highest acceptance/weight ratio of any current experimental technique, are invulnerable to mechanical shocks and temperature excursions associated with space flight, do not employ volatile or explosive components or materials, and are not dependent upon data communications or recording systems. Space-Station personnel would be employed to replace track-sensitive materials as required by background accumulation. Several emulsion-chamber designs are proposed, including both conventional passive calorimetric detectors and a hybrid superconducting-magnetic-spectrometer system. Results of preliminary simulation studies are presented. Operational logistics are discussed.

  5. Radiation processing of polymer emulsion, 8

    International Nuclear Information System (INIS)

    Makuuchi, Keizo; Katakai, Akio; Hagiwara, Miyuki

    1983-01-01

    Radiation induced emulsion copolymerization of strong acid monomer was investigated to reduce the curing temperature of core shell particle emulsion having N-(n-butoxymethyl) acrylamide (NBM) moities in shell part. The strong acid monomers used were 3-chloro-2-acidphosphoxypropyl methacrylate, acid-phosphoxyethyl methacrylate, 2-acrylamide-2-methyl-propane sulfonic acid, and sodium p-styrenesulfonate. Curing was remarkably promoted by the presence of copolymerized strong acid monomer in shell part. Tensile strength of the film cured at 120 0 C was identical with that of conventional NBM core-shell emulsion film cured at 160 0 C. However, the water absorbing capacity of the film cured at 120 0 C was extremely high. The water resistance was found to increase with decreasing the amount of adsorbed polyelectrolyte on the particle surface. (author)

  6. Perfluorooctyl bromide emulsion contrast agent for tumors

    International Nuclear Information System (INIS)

    Tsuda, Yoshio; Ueda, Yasuo; Tanaka, Mikio; Yamanouchi, Kouichi; Yokoyama, Kazumasa

    1985-01-01

    Perfluorooctyl bromide (PFOB), a biologically inert radiodense compound, was evaluated as a potential contrast agent for tumors. When 25 w/v% PFOB emulsion was administered intravenously in rats with AH 130 tumor, the tumor became radiopaque using conventional X-rays. Rabbits were implanted into liver with VX 2 carcinoma and were given 10 ml/kg PFOB emulsion intravenously. Computed tomographic scanning of the rabbits showed the dense enhancement of the rim of the tumor. The PFOB contents in the tumor, the tumor-rim and the normal liver tissues were determined by gas chromatography. The differences of PFOB contents in three different locations showed the density of the tumor rim was due to the accumulation of PFOB in the periphery of the tumor. Optical and electron microscopy revealed lots of vaculoes of PFOB particles in macrophages around the tumor. Thus, PFOB emulsion may be useful in detection of tumors. (author)

  7. Particle tracks in supralinear nuclear research emulsions

    International Nuclear Information System (INIS)

    Larsson, L.; Pinkerton, F.E.; Katz, R.; Benton, E.V.

    1976-01-01

    The tracks of isolated particles in the grain-count regime in emulsion are described by a theory extended from l-hit detectors to c-or-more hit detectors, for study of the tracks of 12 C, 16 O, and 20 Ne ions in a series of desensitized Ilford K-minus emulsions, as processed in a wet hot-stage (Bristol formula) developer. These emulsions represent a class of many-hit nuclear track detectors able to discriminate against low LET radiations, with a threshold that can be varied by processing, and which are able to mimic some of the aspects of the response of biological cells to radiations of different quality

  8. Optimization of cyanide extraction from wastewater using emulsion liquid membrane system by response surface methodology.

    Science.gov (United States)

    Xue, Juan Qin; Liu, Ni Na; Li, Guo Ping; Dang, Long Tao

    To solve the disposal problem of cyanide wastewater, removal of cyanide from wastewater using a water-in-oil emulsion type of emulsion liquid membrane (ELM) was studied in this work. Specifically, the effects of surfactant Span-80, carrier trioctylamine (TOA), stripping agent NaOH solution and the emulsion-to-external-phase-volume ratio on removal of cyanide were investigated. Removal of total cyanide was determined using the silver nitrate titration method. Regression analysis and optimization of the conditions were conducted using the Design-Expert software and response surface methodology (RSM). The actual cyanide removals and the removals predicted using RSM analysis were in close agreement, and the optimal conditions were determined to be as follows: the volume fraction of Span-80, 4% (v/v); the volume fraction of TOA, 4% (v/v); the concentration of NaOH, 1% (w/v); and the emulsion-to-external-phase volume ratio, 1:7. Under the optimum conditions, the removal of total cyanide was 95.07%, and the RSM predicted removal was 94.90%, with a small exception. The treatment of cyanide wastewater using an ELM is an effective technique for application in industry.

  9. Effect of High Pressure Homogenization on the Physicochemical Properties of Natural Plant-based Model Emulsion Applicable for Dairy Products

    Science.gov (United States)

    Park, Sung Hee; Min, Sang-Gi; Jo, Yeon-Ji; Chun, Ji-Yeon

    2015-01-01

    In the dairy industry, natural plant-based powders are widely used to develop flavor and functionality. However, most of these ingredients are water-insoluble; therefore, emulsification is essential. In this study, the efficacy of high pressure homogenization (HPH) on natural plant (chocolate or vanilla)-based model emulsions was investigated. The particle size, electrical conductivity, Brix, pH, and color were analyzed after HPH. HPH significantly decreased the particle size of chocolate-based emulsions as a function of elevated pressures (20-100 MPa). HPH decreased the mean particle size of chocolate-based emulsions from 29.01 μm to 5.12 μm, and that of vanilla-based emulsions from 4.18 μm to 2.44 μm. Electrical conductivity increased as a function of the elevated pressures after HPH, for both chocolate- and vanilla-based model emulsions. HPH at 100 MPa increased the electrical conductivity of chocolate-based model emulsions from 0.570 S/m to 0.680 S/m, and that of vanilla-based model emulsions from 0.573 S/m to 0.601 S/m. Increased electrical conductivity would be attributed to colloidal phase modification and dispersion of oil globules. Brix of both chocolate- and vanilla-based model emulsions gradually increased as a function of the HPH pressure. Thus, HPH increased the solubility of plant-based powders by decreasing the particle size. This study demonstrated the potential use of HPH for enhancing the emulsification process and stability of the natural plant powders for applications with dairy products. PMID:26761891

  10. The role of electrostatics in saliva-induced emulsion flocculation

    NARCIS (Netherlands)

    Silletti, Erika; Vingerhoeds, Monique H.; Norde, Willem; Van Aken, George A.

    Upon consumption food emulsions undergo different processes, including mixing with saliva. It has been shown that whole saliva induces emulsion flocculation [van Aken, G. A., Vingerhoeds, M. H., & de Hoog, E. H. A. (2005). Colloidal behaviour of food emulsions under oral conditions. In E. Dickinson

  11. The role of electrostatistics in saliva-induced emulsion flocculation

    NARCIS (Netherlands)

    Silletti, E.; Vingerhoeds, M.H.; Norde, W.; Aken, van G.A.

    2007-01-01

    Upon consumption food emulsions undergo different processes, including mixing with saliva. It has been shown that whole saliva induces emulsion flocculation [van Aken, G. A., Vingerhoeds, M. H., & de Hoog, E. H. A. (2005). Colloidal behaviour of food emulsions under oral conditions. In E.

  12. Level Recession Of Emissions Release By Motor-And-Tractor Diesel Engines Through The Application Of Water-Fuel Emulsions

    Science.gov (United States)

    Ivanov, A.; Chikishev, E.

    2017-01-01

    The paper is dedicated to a problem of environmental pollution by emissions of hazardous substances with the exhaust gases of internal combustion engines. It is found that application of water-fuel emulsions yields the best results in diesels where production of a qualitative carburetion is the main problem for the organization of working process. During pilot studies the composition of a water-fuel emulsion with the patent held is developed. The developed composition of a water-fuel emulsion provides its stability within 14-18 months depending on mass content of components in it while stability of emulsions’ analogues makes 8-12 months. The mode of operation of pilot unit is described. Methodology and results of pilot study of operation of diesel engine on a water-fuel emulsion are presented. Cutting time of droplet combustion of a water-fuel emulsion improves combustion efficiency and reduces carbon deposition (varnish) on working surfaces. Partial dismantling of the engine after its operating time during 60 engine hours has shown that there is a removal of a carbon deposition in cylinder-piston group which can be observed visually. It is found that for steady operation of the diesel and ensuring decrease in level of emission of hazardous substances the water-fuel emulsion with water concentration of 18-20% is optimal.

  13. Multi-response optimization of diesel engine operating parameters running with water-in-diesel emulsion fuel

    Directory of Open Access Journals (Sweden)

    Vellaiyan Suresh

    2017-01-01

    Full Text Available Water-in-diesel emulsion fuel is a promising alternative diesel fuel, which has the potential to promote better performance and emission characteristics in an existing Diesel engine without engine modification and added cost. The key factor that has to be focused with the introduction of such fuel in existing Diesel engine is desired engine-operating conditions. The present study attempts to address the previous issue with two-phases of experiments. In the first phase, stable water-in-diesel emulsion fuels (5, 10, 15, and 20 water-in-diesel are prepared and their stability period and physico-chemical properties are measured. In the second phase, experiments are conducted in a single cylinder, 4-stroke Diesel engine with pre-pared water-in-diesel emulsion fuel blends based on L16 orthogonal array suggested in Taguchi’s quality control concept to record the output responses (perormance and emission levels. Based on signal-to-noise ratio and grey relational analysis, optimal level of operating factors are determined to obtain better response and verified through confirmation experiments. A statistical analysis of variance is applied to measure the significance of individual operating parameters on overall engine performance. Results indicate that the emulsion fuel prepared by Sorbitan monolaurate surfactant at high stirrer speed endows with better emulsion stability and acceptable variation in physicochemical properties. Results of this study also reveal that the optimal parametric setting effectively improves the combustion, performance, and emission characteristics of Diesel engine.

  14. Study of O/W micro- and nano-emulsions based on propylene glycol diester as a vehicle for geranic acid.

    Science.gov (United States)

    Jaworska, Małgorzata; Sikora, Elżbieta; Ogonowski, Jan; Konieczna, Monika

    2015-01-01

    Nano- and microemulsions containing as the oil phase caprylic/capric propylene glycol diesters (Crodamol PC) were investigated as potential vehicle for controlled release of geranic acid. The influence of emulsifiers and co-surfactants on stability of the emulsions was investigated. Different kind of polysorbates (ethoxylated esters of sorbitan and fatty acids) were applied as the emulsifiers. The short-chain alcohols (ethanol, 1-propanol, 1-butanol) were used as co-surfactants. The emulsions were prepared at ambient temperature (25°C), by the phase inversion composition method (PIC). The stable O/W high dispersed emulsion systems based on Crodamol PC, of mean droplets size less than 200 nm, were prepared. Microemulsions stabilized by the mixture of Polisorbat 80 and 1-butanol were characterized by the largest degree of dispersion (137 nm) and the lowest PDI value (0.094), at surfactant/co-surfactant: oil weight ratio 90:10. The stable nano-emulsion (mean droplet size of 33 nm) was obtained for surfactant: oil (S:O) weight ratio 90:10, without co-surfactant addition. This nano-emulsion was chosen to release studies. The obtained results showed that the prepared stable nano-emulsion can be used as a carrier for controlled release of geranic acid. The active substance release from the nano-emulsion and the oil solution, after 24 hours was 22%.

  15. International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Bolivia. Draft

    International Nuclear Information System (INIS)

    Leroy, Jacques; Mueller-Kahle, Eberhard

    1982-08-01

    The uranium exploration done so far in Bolivia has been carried out by COBOEN, partly with IAEA support, and AGIP S.p.A. of Italy, which between 1974 and 1978 explored four areas in various parts of Bolivia under a production sharing contract with COBOEN. The basic objective of the International Uranium Resources Evaluation Project (IUREP) is to 'review the present body of knowledge pertinent to the existence of uranium resources, to review and evaluate the potential for discovery of additional uranium resources, and to suggest new exploitation efforts which might be carried out in promising areas in collaboration with the country concerned'. Following the initial bibliographic study which formed Phase I of IUREP, it was envisaged that a further assessment in cooperation with, and within, the country concerned would provide a better delineation of areas of high potential and a more reliable estimate as to the degree of favourability for the discovery of additional uranium resources. It was planned that such work would be accomplished through field missions to the country concerned and that these field missions and the resulting report would be known as the Orientation Phase of IUREP. The purpose of the Orientation Phase mission to Bolivia was a) to develop a better understanding of the uranium potential of the country, b) to make an estimate of the Speculative Resources of the country, c) to delineate areas favourable for the discovery of these uranium resources, d) to make recommendations as appropriate on the best methods for evaluating the favourable areas, operating procedures and estimated possible costs, e) to develop the logistical data required to carry out any possible further work, and f) to compile a report which would be immediately available to the Bolivian authorities. The mission reports contains information about a general introduction, non-uranium exploration and mining in Bolivia, manpower in exploration, geological review of Bolivia, past uranium

  16. Food enrichment with marine phospholipid emulsions

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline P.

    of marine PL emulsions, iii) evaluation of non-enzymatic browning reactions in marine PL emulsions, iv) evaluation of sensory properties and oxidative stability of yoghurt enriched with marine PL. The obtained results showed that marine PL have good emulsifying properties and it was feasible to prepare...... to the interaction between lipid oxidation products with amine group either from phosphatidylethanolamine or residues of amino acids/proteins in marine PL. The study on enrichment of yoghurt with marine PL showed that the oxidative stability and sensory acceptability was highly dependent on the quality...

  17. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Zambia

    International Nuclear Information System (INIS)

    1985-01-01

    A report has recently been published which describes the findings of the International Uranium Resources Evaluation Project (IUREP) mission to Zambia. The IUREP Orientation Phase mission to Zambia estimates that the Speculative Resources of that country fall within the range of 33 000 and 100 000 tonnes uranium. The majority of these resources are believed to exist in the Karoo sediments. Other potentially favourable geological environments are the Precambrian Katanga sediments, as well as intrusive rocks of different chemical compositions and surficial duricrusts. Previous unofficial estimates of Zambia's Reasonably Assured Resources (RAR) and Estimated Additional Resources (EAR) are considered to be still valid: the total RAR amount to 6 000 tonnes uranium, located in Karoo (4 000 tonnes) and Katanga (2 000 tonnes) sediments, while the EAR are believed to total 4 000 tonnes being found only in Karoo sediments. The mission recommends that approximately US$ 40 million be spent on uranium exploration in Zambia over 10 years. The largest part of this expenditure would be for drilling, while the remainder should be spent on airborne and ground surveys, as well as on interpretative work on previous airborne data, Landsat imageries, etc. (author)

  18. International Uranium Resources Evaluation Project (IUREP) orientation phase mission summary report: Somalia

    International Nuclear Information System (INIS)

    1985-01-01

    A full report has been compiled describing the findings of the International Uranium Resources Evaluation Project (IUREP) Orientation Phase Mission to Somalia. The Mission suggests that in addition to the reasonably assured resources (RAR) of 5 000 t uranium and estimated additional resources (EAR) of 11 000 t uranium in calcrete deposits, the speculative resources (SR) could be within the wide range of 0 - 150 000 t uranium. The majority of these speculative resources are related to sandstone and calcrete deposits. The potential for magmatic hydrothermal deposits is relatively small. The Mission recommends an exploration programme of about US$ 22 000 000 to test the uranium potential of the country which is thought to be excellent. The Mission also suggests a reorganization of the Somalia Geological Survey in order to improve its efficiency. Recommended methods include geological mapping, Landsat imagery interpretation, airborne and ground scintillometer surveys, and geochemistry. Follow-up radiometric surveys, exploration geophysics, mineralogical studies, trenching and drilling are proposed in favourable areas. (author)

  19. LET dependence of bubbles evaporation pulses in superheated emulsion detectors

    Science.gov (United States)

    Di Fulvio, Angela; Huang, Jean; Staib, Lawrence; d'Errico, Francesco

    2015-06-01

    Superheated emulsion detectors are suspensions of metastable liquid droplets in a compliant inert medium. Upon interaction with ionizing radiation, the droplets evaporate, generating visible bubbles. Bubble expansion associated with the boiling of the droplets is accompanied by pressure pulses in both the sonic and ultrasonic frequency range. In this work, we analyzed the signal generated by bubble evaporation in the frequency and time domain. We used octafluoropropane (R-218) based emulsions, sensitive to both photons and neutrons. The frequency content of the detected pulses appears to extend well into the hundreds of kHz, beyond the range used in commercial devices to count bubbles as they are formed (typically 1-10 kHz). Kilohertz components characterize the early part of the waveforms, potentially containing information about the energetics of the explosive bubble initial growth phase. The power spectral density of the acoustic signal produced by neutron-induced evaporation shows a characteristic frequency pattern in the 200-400 kHz range, which is not observed when bubbles evaporate upon gamma ray-induced irradiation. For practical applications, detection of ultrasonic pulses associated with the boiling of the superheated drops can be exploited as a fast readout method, negligibly affected by mechanical ambient noise.

  20. A comparison of water-diesel emulsion and timed injection of water into the intake manifold of a diesel engine for simultaneous control of NO and smoke emissions

    International Nuclear Information System (INIS)

    Subramanian, K.A.

    2011-01-01

    Experiments were conducted to compare the effects of water-diesel emulsion and water injection into the intake manifold on performance, combustion and emission characteristics of a DI diesel engine under similar operating conditions. The water to diesel ratio for the emulsion was 0.4:1 by mass. The same water-diesel ratio was maintained for water injection method in order to assess both potential benefits. All tests were done at the constant speed of 1500 rpm at different outputs. The static injection timing of 23 o BTDC was kept as constant for all experimental tests. In the first phase, experiments were carried out to asses the performance, combustion and emission characteristics of the engine using the water-diesel emulsion. The emulsion was prepared using the surfactant of HLB:7. The emulsion was injected using the conventional injection system during the compression stroke. The second phase of work was that water was injected into the intake manifold of the engine using an auxiliary injector during the suction stroke. An electronic control unit (ECU) was developed to control the injector operation such as start of injection and water injection duration with respect to the desired crank angle. The experimental result indicates the both methods (emulsion and injection) could reduce NO emission drastically in diesel engines. At full load, NO emission decreased drastically from 1034 ppm with base diesel to 645 ppm with emulsion and 643 ppm with injection. But, NO emission reduction is lesser with injection than emulsion at part loads. Smoke emission is lower with the emulsion (2.7 BSU) than with water injection (3.2 BSU) as compared to base diesel (3.6 BSU). However, CO and HC levels were higher with emulsion than water injection. As regards NO and smoke reduction, the emulsion was superior to injection at all loads. Peak pressure, ignition delay and maximum rate of pressure rise were lesser with water injection as compared to the emulsion. It is well demonstrated

  1. Performance of automatic scanning microscope for nuclear emulsion experiments

    Science.gov (United States)

    Güler, A. Murat; Altınok, Özgür

    2015-12-01

    The impressive improvements in scanning technology and methods let nuclear emulsion to be used as a target in recent large experiments. We report the performance of an automatic scanning microscope for nuclear emulsion experiments. After successful calibration and alignment of the system, we have reached 99% tracking efficiency for the minimum ionizing tracks that penetrating through the emulsions films. The automatic scanning system is successfully used for the scanning of emulsion films in the OPERA experiment and plan to use for the next generation of nuclear emulsion experiments.

  2. The use of fluorocarbon emulsions in cancer radiotherapy

    International Nuclear Information System (INIS)

    Guichard, M.

    1991-01-01

    The chemical and physical properties of perfluorochemical emulsions which highlight their advantages and disadvantages for use in cancer radiotherapy are summarized. The radiobiological properties of two emulsions are reviewed: the authors have chosen the Fluosol-DA 20% and the PFOB emulsion 100 v/w% which is one of the most promising second generation fluorocarbon emulsions. The radiosensitization obtained in a human tumor xenograft with PFOB emulsion is compared to that obtained with other modalities used to overcome the radioresistance of tumor cells linked to hypoxia. (author). 27 refs.; 2 figs.; 1 tab

  3. Nanocellulose-stabilized Pickering emulsions and their applications.

    Science.gov (United States)

    Fujisawa, Shuji; Togawa, Eiji; Kuroda, Katsushi

    2017-01-01

    Pickering emulsion, which is an emulsion stabilized by solid particles, offers a wide range of potential applications because it generally provides a more stable system than surfactant-stabilized emulsion. Among various solid stabilizers, nanocellulose may open up new opportunities for future Pickering emulsions owing to its unique nanosizes, amphiphilicity, and other favorable properties (e.g. chemical stability, biodegradability, biocompatibility, and renewability). In this review, the preparation and properties of nanocellulose-stabilized Pickering emulsions are summarized. We also provide future perspectives on their applications, such as drug delivery, food, and composite materials.

  4. The effect of some processing conditions on the characteristics of biodegradable microspheres obtained by an emulsion solvent evaporation process

    Directory of Open Access Journals (Sweden)

    J. L. Maia

    2004-01-01

    Full Text Available Unloaded microspheres were prepared from polyhydroxybutyrate (PHB and polyhydroxybutyrate-co-valerate (PHB-HV polymers using an oil-in-water emulsion solvent evaporation method. The study was conducted to evaluate how the polymer and some process parameters affect properties of the final microspheres such as particle size, superficial area, zeta potential, surface morphology and microsphere degradation. The variables included surfactant concentration in the emulsion water phase and solvent composition. From the results, it was found that the parameters affecting microsphere size the most were surfactant concentration in the emulsion water phase and solvent composition. Properties such as zeta potential, surface area and surface morphology remained pratically unchanged over the range of the processing conditions studied here.

  5. CMS emulsion pictures during LS1

    CERN Multimedia

    Di Ferdinando, Donato

    2013-01-01

    These images were taken at the CMS experimental cavern during Long Shutdown 1, installing pinhole cameras at different points of the cavern and exposing them for days. The development of the film was done by Donato di Ferdinando from INFN Bologna. A pinhole camera is a light-tight box where a small hole is made (diameter of the order of microns); a light-sensitive material is set in the back of the hole. As sensitive material a nuclear emulsion film from the OPERA experiment was used. It is a special photographic emulsion optimized (silver grains enriched) for the detection of charged particles. A very large amount of nuclear emulsions where used in Opera experiment, at the Gran Sasso Underground Labs; nuclear emulsions must detect the charged tau-leptons emerging from the interaction between the "oscillated" tau-neutrino coming from the pure muon-neutrino beam produced at CERN (the CNGS beam). The oscillations theory of neutrino expects that muon neutrinos oscillate to tau-neutrinos and due to this behavior ...

  6. Rheological and textural properties of cosmetic emulsions

    Czech Academy of Sciences Publication Activity Database

    Morávková, Tereza; Štern, Petr

    2011-01-01

    Roč. 21, č. 3 (2011), č. článku 35200. ISSN 1430-6395 Institutional research plan: CEZ:AV0Z20600510 Keywords : cosmetic emulsions * rheology * texture * sensory analysis * psychorheology Subject RIV: BK - Fluid Dynamics Impact factor: 1.000, year: 2011

  7. Fouling reduction by ozone-enhanced backwashing process in ultrafiltration of petroleum-based oil in water emulsion

    Science.gov (United States)

    Aryanti, Nita; Prihatiningtyas, Indah; Kusworo, Tutuk Djoko

    2017-06-01

    Ultrafiltration membrane has been successfully applied for oily waste water treatment. However, one significant drawback of membrane technology is fouling which is responsible for permeate flux decline as well as reducing membrane performance. One method commonly used to reduce fouling is a backwashing process. The backwashing is carried out by a push of reversed flow from permeate side to the feed side of a membrane to remove fouling on the membrane pore and release fouling release fouling layer on the external side. However, for adsorptive fouling, the backwashing process was not effective. On the other hand, Ozone demonstrated great performance for reducing organics fouling. Hence this research was focused on backwashing process with ozone for removing fouling due to ultrafiltration of petroleum based oil emulsion. Gasoline and diesel oil were selected as dispersed phase, while as continuous phase was water added with Tween 80 as a surfactant. This research found that the Ozone backwashing was effective to improve flux recovery. In ultrafiltration of gasoline emulsion, the flux recovery after Ozone backwashing was in the range of 42-74%. For ultrafiltration of diesel oil emulsion, the permeate flux recovery was about 35-84%. In addition, foulant deposition was proposed and predicting that foulant deposition for ultrafiltration of gasoline-in-water emulsion was surfactant as the top layer and the oil was underneath the surfactant. On the other hand, for ultrafiltration of diesel oil-in-water emulsion, the oil was predicted as a top layer above the surfactant foulant.

  8. Synthetic Polymers at Interfaces: Monodisperse Emulsions Multiple Emulsions and Liquid Marbles

    Science.gov (United States)

    Sun, Guanqing

    The adsorption of polymeric materials at interfaces is an energetically favorable process which is investigated in much diversified fields, such as emulsions, bubbles, foams, liquid marbles. Pickering emulsion, which is emulsion stabilized by solid particles has been investigated for over one century and preparation of Pickering emulsion with narrow size distribution is crucial for both the theoretical study of the stabilization mechanism and practical application, such as templated fabrication of colloidosomes. The precise control over the size and functionality of polymer latices allows the preparation of monodisperse Pickering emulsions with desired sizes through SPG membrane emulsification at rather rapid rate compared to microfludic production. Double or multiple emulsions have long been investigated but its rapid destabilization has always been a major obstacle in applying them into practical applications. The modern living polymerization techniques allow us to prepare polymers with designed structure of block copolymers which makes it possible to prepare ultra-stable multiple emulsions. The precise tuning of the ratio of hydrophobic part over the hydrophilic can unveil the stabilization mechanism. Liquid marble is a new type of materials of which liquid droplets are coated by dry particles. The coating of an outer layer of dry particles renders the liquid droplets non-sticky at solid surface which is useful in transportation of small amount of liquid without leakage at extreme low friction force. The property of liquid marbles relies largely on the stabilizers and the drying condition of polymeric latices is shown to have great influence on the property of liquid marbles. Firstly, an introduction to the interfacial and colloidal science with special attention to topics on emulsions, multiple emulsion and liquid marbles is given in Chapter 1. The unique features of an interface and a discussion on the definition of colloids are introduced prior to the

  9. Recycling nanoparticle catalysts without separation based on a pickering emulsion/organic biphasic system.

    Science.gov (United States)

    Liu, Huifang; Zhang, Zhiming; Yang, Hengquan; Cheng, Fangqin; Du, Zhiping

    2014-07-01

    A conceptually novel methodology is explored for in situ recycling of nanoparticle catalysts based on transforming a conventional organic/aqueous biphasic system into a Pickering emulsion/organic biphasic system (PEOBS). The suggested PEOBS exists as two phases, with the nanoparticle catalyst "anchored" in the Pickering emulsion phase, but is "continuous" between the organic phase and the continuous phase of the Pickering emulsion. Aqueous hydrogenations are used to evaluate the reaction performances of PEOBS, and the underlying principles of PEOBS are preliminarily elaborated. The unique properties of PEOBS lead to many intriguing findings, which are unlikely to be achieved in the reported biphasic systems. PEOBS exhibits more than a fourfold enhancement in catalysis efficiency in comparison with a conventional biphasic system. Impressively, PEOBS enables the organic product to be facilely isolated through simple decantation and the nanoparticle catalyst can be recycled in situ without the need for "separation". Its recycling effectiveness is justified by ten reaction cycles without significant catalyst loss. The simple protocol, in conjunction with the stability to simultaneously achieve high catalysis efficiency and excellent catalyst recyclability, makes PEOBS a promising methodology to develop more sustainable nanocatalysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Formation of oil-in-water emulsions from natural emulsifiers using spontaneous emulsification: sunflower phospholipids.

    Science.gov (United States)

    Komaiko, Jennifer; Sastrosubroto, Ashtri; McClements, David Julian

    2015-11-18

    This study examined the possibility of producing oil-in-water emulsions using a natural surfactant (sunflower phospholipids) and a low-energy method (spontaneous emulsification). Spontaneous emulsification was carried out by titrating an organic phase (oil and phospholipid) into an aqueous phase with continuous stirring. The influence of phospholipid composition, surfactant-to-oil ratio (SOR), initial phospholipids location, storage time, phospholipid type, and preparation method was tested. The initial droplet size depended on the nature of the phospholipid used, which was attributed to differences in phospholipid composition. Droplet size decreased with increasing SOR and was smallest when the phospholipid was fully dissolved in the organic phase rather than the aqueous phase. The droplets formed using spontaneous emulsification were relatively large (d > 10 μm), and so the emulsions were unstable to gravitational separation. At low SORs (0.1 and 0.5), emulsions produced with phospholipids had a smaller particle diameter than those produced with a synthetic surfactant (Tween 80), but at a higher SOR (1.0), this trend was reversed. High-energy methods (microfluidization and sonication) formed significantly smaller droplets (d < 10 μm) than spontaneous emulsification. The results from this study show that low-energy methods could be utilized with natural surfactants for applications for which fine droplets are not essential.

  11. Interfacial and oil/water emulsions characterization of potato protein isolates.

    Science.gov (United States)

    Romero, Alberto; Beaumal, Valérie; David-Briand, Elisabeth; Cordobés, Felipe; Guerrero, Antonio; Anton, Marc

    2011-09-14

    Interfacial and emulsifying properties of potato protein isolate (PPI) have been studied to evaluate its potential application to stabilize oil/water emulsions at two pH values (2 and 8). The amount, type, and solubility of proteins and the size of aggregates have been determined in aqueous dispersion. Air-water and oil-water interfacial properties (adsorption, spreading, and viscoelastic properties) have been determined as a function of concentration and pH using soluble phases of PPI. The behavior of PPI stabilized oil/water emulsions has been then analyzed by droplet size distribution measurements and interfacial concentration. PPI exhibits low solubility over a wide range of pH values, with the presence of submicrometer aggregates. The pH value exerts a negligible effect on interfacial tension (oil-water) or surface pressure (air-water) but displays very important differences in viscoelastic properties of the interfacial films formed between oil and water. In this sense, pH 8 provides a major elastic response at oil-water interfaces as compared to pH 2. In relation with this result, a much higher ability to produce fine and stable emulsions is noticed at pH 8 as compared to pH 2. Consequently, there is an evident relationship between the rheological properties of the oil-water interfacial films and the macroscopic emulsion behavior.

  12. Versatile Methodology to Encapsulate Gold Nanoparticles in PLGA Nanoparticles Obtained by Nano-Emulsion Templating.

    Science.gov (United States)

    Fornaguera, Cristina; Feiner-Gracia, Natàlia; Dols-Perez, Aurora; García-Celma, Maria José; Solans, Conxita

    2017-05-01

    Gold nanoparticles have been proved useful for many biomedical applications, specifically, for their use as advanced imaging systems. However, they usually present problems related with stability and toxicity. In the present work, gold-nanoparticles have been encapsulated in polymeric nanoparticles using a novel methodology based on nano-emulsion templating. Firstly, gold nanoparticles have been transferred from water to ethyl acetate, a solvent classified as class III by the NIH guidelines (low toxic potential). Next, the formation of nano-emulsions loaded with gold nanoparticles has been performed using a low-energy, the phase inversion composition (PIC) emulsification method, followed by solvent evaporation giving rise to polymeric nanoparticles. Using this methodology, high concentrations of gold nanoparticles (>100 pM) have been encapsulated. Increasing gold nanoparticle concentration, nano-emulsion and nanoparticle sizes increase, resulting in a decrease on the stability. It is noteworthy that the designed nanoparticles did not produce cytotoxicity neither hemolysis at the required concentration. Therefore, it can be concluded that a novel and very versatile methodology has been developed for the production of polymeric nanoparticles loaded with gold nanoparticles. Graphical Abstract Schematic representation of AuNP-loaded polymeric nanoparticles preparation from nano-emulsion templating.

  13. Fabrication of yttria microcapsules for radiotherapy from water/oil emulsion

    International Nuclear Information System (INIS)

    Miyazaki, Toshiki; Kai, Tomohiro; Ishida, Eiichi; Kawashita, Masakazu; Hiraoka, Masahiro

    2010-01-01

    Radiotherapy using ceramic microparticles that act as β-emitters after neutron bombardment is attractive as a minimally invasive option for cancer treatment. Yttria (Y 2 O 3 ) microcapsules (20-30 μm in diameter) are capable of cutting off the nutrition supply in cancer cells through an embolization effect. In the present study, Y 2 O 3 microcapsules were prepared via precipitation of yttrium hydroxide from a water/oil (W/O) emulsion and a subsequent heat treatment. The emulsion was prepared by dispersing yttrium hydroxide sol in 2-ethyl-1-hexanol. Microcapsules were obtained by an addition of the emulsion in butanol via dehydration and subsequent aggregation of the yttrium hydroxide. The effects of the rotation speed and surfactant concentration on the diameter of the particles were investigated. The diameter of the microcapsules showed a tendency to decrease with increases in rotation speed during emulsion preparation or surfactant concentration in the oil phase. A high yield of the Y 2 O 3 microcapsules with a diameter of 20-30 μm were obtained after a heat treatment at the optimized rotation speed and surfactant concentration. The obtained microcapsules showed high chemical durability in a simulated body environment. (author)

  14. INTERFACIAL ENERGY DURING THE EMULSIFICATION OF WATER-IN-HEAVY CRUDE OIL EMULSIONS

    Directory of Open Access Journals (Sweden)

    V. Karcher

    2015-03-01

    Full Text Available Abstract The aim of this study was to investigate the interfacial energy involved in the production of water-in-oil (W/O emulsions composed of water and a Brazilian heavy crude oil. For such purpose an experimental set-up was developed to measure the different energy terms involved in the emulsification process. W/O emulsions containing different water volume fractions (0.1, 0.25 and 0.4 were prepared in a batch calorimeter by using a high-shear rotating homogenizer at two distinct rotation speeds (14000 and 22000 rpm. The results showed that the energy dissipated as heat represented around 80% of the energy transferred to the emulsion, while around 20% contributed to the internal energy. Only a very small fraction of the energy (0.02 - 0.06% was stored in the water-oil interface. The results demonstrated that the high energy dissipation contributes to the kinetic stability of the W/O emulsions.

  15. Investigation on frictional pressure drop of steam-water two-phase flow in an internally ribbed tube

    International Nuclear Information System (INIS)

    Li Yongxing; Chen Tingkuan; Li Huixiong

    2005-01-01

    Within the range of pressures from 9 to 22 MPa, mass velocities from G 600 to 1200 kg/(m 2 ·s), and heat fluxes from x 0 to 1.0, experiments had performed to investigate the frictional pressure drop of the steam-water two-phase flow in a six-head internally ribbed tube with the outer diameter of 38.1 mm and the thickness of 7.5 mm. The test section was thermally insulated as horizontal direction. Based on the experimental results, it was found that pressure had a noticeable effect on the frictional pressure drop of the mental results, and that pressure had a noticeable effect on the frictional pressure drop of the steam-water two-phase flow, and the frictional pressure drop factor of the steam-water two-phase flow decreased with an increase in pressure. The frictional pressure drop factor of the steam-water two-phase flow tends to one near the critical pressure. As steam quality increased, the frictional pressure drop factor of the steam-water two-phase flow first increased, and then it had a decreasing tendency. With an increase in mass velocity, the frictional pressure drop factor of the steam-water two-phase flow decreased. Correlations of the frictional pressure drop factor of the steam-water two-phase flow had been provided. (authors)

  16. Coating individual single-walled carbon nanotubes with nylon 6,10 through emulsion polymerization.

    Science.gov (United States)

    Chen, Wei-Chiang; Wang, Randy K; Ziegler, Kirk J

    2009-08-01

    Solvent microenvironments are formed around individual single-walled carbon nanotubes (SWNTs) by mixing SWNT suspensions with water-immiscible organic solvents. These microenvironments are used to encapsulate the SWNTs with the monomer sebacoyl chloride. Hexamethylene diamine is then injected into the aqueous phase so the formation of nylon 6,10 is restricted to the interface between the microenvironment and water. This emulsion polymerization process results in uniform coatings of nylon 6,10 around individual SWNTs. The nylon-coated SWNTs remain dispersed in the aqueous phase and are highly luminescent at pH values ranging from 3 to 12. This emulsion polymerization method provides a general approach to coat nanotubes with various polymers.

  17. Emulsion-Based RIR-MAPLE Deposition of Conjugated Polymers: Primary Solvent Effect and Its Implications on Organic Solar Cell Performance.

    Science.gov (United States)

    Ge, Wangyao; Li, Nan K; McCormick, Ryan D; Lichtenberg, Eli; Yingling, Yaroslava G; Stiff-Roberts, Adrienne D

    2016-08-03

    Emulsion-based, resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) has been demonstrated as an alternative technique to deposit conjugated polymer films for photovoltaic applications; yet, a fundamental understanding of how the emulsion target characteristics translate into film properties and solar cell performance is unclear. Such understanding is crucial to enable the rational improvement of organic solar cell (OSC) efficiency and to realize the expected advantages of emulsion-based RIR-MAPLE for OSC fabrication. In this paper, the effect of the primary solvent used in the emulsion target is studied, both experimentally and theoretically, and it is found to determine the conjugated polymer cluster size in the emulsion as well as surface roughness and internal morphology of resulting polymer films. By using a primary solvent with low solubility-in-water and low vapor pressure, the surface roughness of deposited P3HT and PCPDTBT polymer films was reduced to 10 nm, and the efficiency of P3HT:PC61BM OSCs was increased to 3.2% (∼100 times higher compared to the first MAPLE OSC demonstration [ Caricato , A. P. ; Appl. Phys. Lett. 2012 , 100 , 073306 ]). This work unveils the mechanism of polymer film formation using emulsion-based RIR-MAPLE and provides insight and direction to determine the best ways to take advantage of the emulsion target approach to control film properties for different applications.

  18. Surface Polarization Effects on Ion-Containing Emulsions

    Science.gov (United States)

    Shen, Meng; Li, Honghao; Olvera de la Cruz, Monica

    2017-09-01

    Surface polarization in ion-containing heterogeneous dielectric media such as cell media and emulsions is determined by and determines the positions of the ions. We compute the surface polarization self-consistently as the ions move and analyze their effects on the interactions between electro-neutral, ion-containing droplets using coarse-grained molecular dynamics simulations based on the true energy functional. For water droplets immersed in oil, the interdroplet interaction is attractive, and the surface polarization makes the major contribution. By contrast, for oil droplets in water, the ion-surface induced charge interaction is repulsive and counteracts the attraction between the ions, leading to a small attractive interaction between the droplets. This research improves our understanding of self-assembly in mixed phases such as metal extraction for recovering rare earth elements and nuclear waste as well as water purification.

  19. Thermodynamically stable emulsions using Janus dumbbells as colloid surfactants.

    Science.gov (United States)

    Tu, Fuquan; Park, Bum Jun; Lee, Daeyeon

    2013-10-15

    One of the most important properties of emulsions is their stability. Most emulsions stabilized with molecular surfactants tend to lose their stability over time via different mechanisms. Although the stability of emulsions stabilized with homogeneous particles have been shown to be superior to that of surfactant-stabilized emulsions, these Pickering emulsions nevertheless are only kinetically stable and thus can undergo destabilization. Janus particles that have two opposite wetting surfaces have shown promise in imparting emulsions with long-term stability because of their strong attachment to the oil-water interface. In this theoretical study, we consider thermodynamics of emulsion stabilization using amphiphilic Janus dumbbells, which are nonspherical particles made of two partially fused spherical particles of opposite wettability. These amphiphilic dumbbells are attractive candidates as colloid surfactants for emulsion stabilization because highly uniform Janus dumbbells can be synthesized in large quantities; thus, their application in emulsion stabilization can become practical. Our theoretical calculation demonstrates that Janus dumbbells can indeed generate thermodynamically stable Pickering emulsions. In addition, we also find that there exists a total oil-water interfacial area that results in the lowest energy state in the system, which occurs when Janus dumbbells available in the system are completely consumed to fully cover the droplet interfaces. We show that the geometry of dumbbells as well as the composition of the emulsion mixtures has significant influences on the average size of dumbbell-stabilized emulsions. We also investigate the effect of asymmetry of Janus dumbbells on the average droplet radius. Our results clearly show that amphiphilic Janus dumbbells provide unique opportunities in stabilizing emulsions for various applications.

  20. International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Republic of Burundi. Draft

    International Nuclear Information System (INIS)

    Gehrisch, W.; Chaigne, M.

    1983-06-01

    The basic objective of the International Uranium Resources Evaluation project lUREP is to 'Review the present body of knowledge pertinent to the existence of uranium resources, to review and evaluate the potential for the discovery of additional uranium resources and to suggest new exploration efforts which might be carried out in promising areas in collaboration with the countries concerned'. Therefore, the scope of the IUREP orientation phase Mission to Burundi was to review all data on past exploration in Burundi, to develop a better understanding of the uranium potential of the country, to make an estimate of the speculative resources of the country, to make recommendation as appropriate on the best methods or techniques for evaluating the resources in the favourable areas and for estimating possible costs as well, to compile a report which could be immediately available to the Burundian authorities. This mission gives a general introduction, a geological review of Burundi, information on non-uranium mining in Burundi, the history of uranium exploration, occurrences of uranium IUREP mission field reconnaissance, favourable areas for speculative potential, the uranium resources position and recommendations for future exploration. Conclusions are the following. The IUREP Orientation -phase mission to Burundi believes that the Speculative Resources of that country fall b etween 300 and 4100 tons uranium oxide but a less speculative appraisal is more likely between 0 and 1000 tons. There has been no uranium production and no official estimates of Uranium Resources in Burundi. Past exploration mainly dating from 1969 onwards and led the UNDP Mineral project has indicated a limited number of uranium occurrences and anomalies. The speculative uranium resources are thought to be possibly associated with potential unconformity related vein-like deposits of the Lower Burundian. Other speculative uranium resources could be associated with granitic or peribatholitic

  1. Oil-in-water Pickering emulsions stabilized by colloidal particles from the water-insoluble protein zein

    NARCIS (Netherlands)

    de Folter, J.W.J.; van Ruijven, M.W.M.; Velikov, K.

    2012-01-01

    Few fully natural and biocompatible materials are available for the effective particle-stabilization of emulsions since strict requirements, such as insolubility in both fluid phases and intermediate wettability, need to be met. In this paper, we demonstrate the first use of water-insoluble

  2. International regulatory issues and approaches in the transition phase from operation to decommissioning

    International Nuclear Information System (INIS)

    Pyy, P.; Hrehor, M.; ); Murley, T.; Ranieri, R.; Laaksonen, J.

    2005-01-01

    Full text: The paper summarizes the work performed by an international group of senior nuclear safety regulators which was convened by the Committee on Nuclear Regulatory Activities (CNRA) of the OECD/Nuclear Energy Agency. The fundamental objective of this work was to identify the safety, environmental, organizational, human factors and public policy issues arising from decommissioning that will produce new challenges for the regulator. The study begins by recognizing that decommissioning is not simply an extension of operation and thus it is important for both the management of the facility and the regulator to understand the fundamental nature of the change taking place. Major regulatory policy issues discussed during this study include assurance of adequate funds, waste storage and disposal sites, material release criteria and site release criteria. Some of the important regulatory challenges relate to organizational and human factors, to safety and security requirements and to waste disposal and license termination. The importance of regular communication with both the corporate and site management and with public is recognized in the study as one of the key factors. When a nuclear facility ceases operation and enters into the decommissioning phase, both the operator and the regulator face a new set of challenges very different from those of an operating facility. The operator should have in place a strategic plan for decommissioning, prepared well in advance and reviewed by the regulatory body, to guide the facility managers and personnel through the changed circumstances. An essential part of the strategic plan should be the operator's plan for securing adequate funds to complete the decommissioning activities. In fact, the regulator should ensure that the operator sets aside funds, perhaps in a trust fund, while the facility is still operating and generating revenues. Both the operator and the regulator should expect a heightened public interest and concern

  3. Layer-by-layer encapsulated nano-emulsion of ionic liquid loaded with functional material for extraction of Cd2+ions from aqueous solutions.

    Science.gov (United States)

    Elizarova, Iuliia S; Luckham, Paul F

    2017-04-01

    Ionic liquids can serve as an environmentally-friendly replacement for solvents in emulsions, therefore they are considered suitable to be used as an emulsified medium for various active materials one of which are extractors of metal ions. Increasing the extraction efficiency is considered to be one of the key objectives when working with such extraction systems. One way to improve the extraction efficiency is to increase the contact area between the extractant and the working ionic solution. This can be accomplished by creating a nano-emulsion of ionic liquid containing such an extractant. Since emulsification of ionic liquid is not always possible in the sample itself, there is a necessity of creating a stable emulsion that can be added externally and on demand to samples from which metal ions need to be extracted. We propose a method of fabrication of a highly-stable extractant-loaded ionic liquid-in-water nano-emulsion via a low-energy phase reversal emulsification followed by continuous layer-by-layer polyelectrolyte deposition process to encapsulate the nano-emulsion and enhance the emulsion stability. Such a multilayered stabilized nano-emulsion was tested for extraction of Cd 2+ and Ca 2+ ions in order to determine its extraction efficiency and selectivity. It was found to be effective in the extraction of Cd 2+ ions with near 100% cadmium removal, as well as being selective since no Ca 2+ ions were extracted. The encapsulated emulsion was removed from samples post-extraction using two methods - filtration and magnetic separation, both of which were shown to be viable under different circumstances - larger and mechanically stronger capsules could be removed by filtration, however magnetic separation worked better for both smaller and bigger capsules. The long-term stability of nano-emulsion was also tested being a very important characteristic for its proposed use: it was found to be highly stable after four months of storage time. Copyright © 2016

  4. Development and characterization of functional O/W emulsions with chia seed (Salvia hispanica L.) by-products

    OpenAIRE

    Julio, Luciana Magdalena; Ixtaina, Vanesa Yanet; Fernández, Mariela; Torres Sánchez, Rosa Maria; Nolasco, Susana María; Tomás, Mabel Cristina

    2016-01-01

    The present work investigated the physicochemical properties of O/W emulsions containing functional ingredients (oil with high ω-3 fatty acid content, protein and/or soluble fiber) from chia seeds. The effect of different protein–carbohydrate combinations (sodium caseinate and lactose, sodium caseinate and maltodextrin, chia protein-rich fraction and maltodextrin) and the presence of chia mucilage (0 and 0.2 % wt/wt) in the aqueous phase of chia O/W emulsions was studied as a function of drop...

  5. Emulsion characteristics, chemical and textural properties of meat systems produced with double emulsions as beef fat replacers.

    Science.gov (United States)

    Serdaroğlu, Meltem; Öztürk, Burcu; Urgu, Müge

    2016-07-01

    In recent years, double emulsions are stated to have a promising potential in low-fat food production, however, there are very few studies on their possible applications in meat matrices. We aimed to investigate the quality of beef emulsion systems in which beef fat was totally replaced by double emulsions (W1/O/W2) prepared with olive oil and sodium caseinate (SC) by two-step emulsification procedure. Incorporation of W1/O/W2 emulsion resulted in reduced lipid, increased protein content, and modified fatty acid composition. W1/O/W2 emulsion treatments had lower jelly and fat separation, higher water-holding capacity and higher emulsion stability than control samples with beef fat. Increased concentrations of W1/O/W2 emulsions resulted in significant changes in texture parameters. TBA values were lower in W1/O/W2 emulsion treatments than control treatment after 60days of storage. In conclusion, our study confirms that double emulsions had promising impacts on modifying fatty acid composition and developing both technologically and oxidatively stable beef emulsion systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. A Comparative Study of the Physicochemical Properties of a Virgin Coconut Oil Emulsion and Commercial Food Supplement Emulsions

    Directory of Open Access Journals (Sweden)

    Yih Phing Khor

    2014-07-01

    Full Text Available Food manufacturers are interested in developing emulsion-based products into nutritional foods by using beneficial oils, such as fish oil and virgin coconut oil (VCO. In this study, the physicochemical properties of a VCO oil-in-water emulsion was investigated and compared to other commercial oil-in-water emulsion products (C1, C2, C3, and C4. C3 exhibited the smallest droplet size of 3.25 µm. The pH for the emulsion samples ranged from 2.52 to 4.38 and thus were categorised as acidic. In a texture analysis, C2 was described as the most firm, very adhesive and cohesive, as well as having high compressibility properties. From a rheological viewpoint, all the emulsion samples exhibited non-Newtonian behaviour, which manifested as a shear-thinning property. The G'G'' crossover illustrated by the VCO emulsion in the amplitude sweep graph but not the other commercial samples illustrated that the VCO emulsion had a better mouthfeel. In this context, the VCO emulsion yielded the highest zeta potential (64.86 mV, which was attributed to its strong repulsive forces, leading to a good dispersion system. C2 comprised the highest percentage of fat among all emulsion samples, followed by the VCO emulsion, with 18.44% and 6.59%, respectively.

  7. Preparation and Characterization of Silicone Liquid Core/Polymer Shell Microcapsules via Internal Phase Separation

    DEFF Research Database (Denmark)

    Gonzalez, Lidia; Kostrzewska, Malgorzata; Ma, Baoguang

    2014-01-01

    Microcapsules with a silicone liquid core surrounded by a polymeric shell were synthesisedthrough the controlled phase separation. The dispersed silicone phase consisted of the shellpolymer PMMA, a good solvent for the PMMA (dichloromethane, DCM) and a poor solvent(methylhydrosiloxane dimethylsil......Microcapsules with a silicone liquid core surrounded by a polymeric shell were synthesisedthrough the controlled phase separation. The dispersed silicone phase consisted of the shellpolymer PMMA, a good solvent for the PMMA (dichloromethane, DCM) and a poor solvent......(methylhydrosiloxane dimethylsiloxane) for thePMMA. The morphology of the PMMA micro-capsules was investigated by ATR-FTIR and byoptical microscopy. Microcapsules were preparedwith different emulsifiers and different concen-trations of acetone and PMMA in the oil phase.The thermal stability of the PMMA microcapsuleand the content...... of the silicone oil core wereassessed by TGA.1H-NMR spectroscopy and anextraction method were also used to determine the content of the silicone liquid core in the microcapsules....

  8. α-Tocopherol/chitosan-based nanoparticles: characterization and preliminary investigations for emulsion systems application

    Science.gov (United States)

    Aresta, Antonella; Calvano, Cosima Damiana; Trapani, Adriana; Zambonin, Carlo Giorgio; De Giglio, Elvira

    2014-02-01

    The processes of lipids oxidation represent a great concern for the consumer health because they are one of the major causes of quality deterioration in fat-containing products. One of the most effective methods of delaying lipid oxidation consists in incorporating antioxidants. The present investigation describes the formulation of chitosan and novel glycol chitosan nanoparticles (NPs) loaded with α-Tocopherol (αToc-NPs). The obtained NPs were characterized by various techniques, such as particle size (showing mean diameters in the range 335-503 nm) and zeta potential measurements, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The NPs were, then, added in the preparation of oil-in-water simple emulsion both to make the lipophilic αToc available in an aqueous medium and to prevent emulsion oxidation. For this purpose, a new highly sensitive, simple and solvent-free method based on a solid phase microextraction (SPME) coupled to gas chromatography mass spectrometry was developed for the determination of αToc in aqueous medium. All the parameters influencing SPME, including fiber coating, time and temperature extraction, pH, ionic strength and desorption conditions, have been carefully screened. The method was successfully applied to the determination of vitamin in the αToc-NPs and its release from NPs-enriched simple emulsion formulations. SPME provided high recovery yields and the limits of detection and of quantification in emulsion were 0.1 and 0.5 μg/mg, respectively. The precision of the method has been also estimated. The delay of the lipid oxidation by the proposed formulations has been evaluated exploiting the Kreis test on αToc-NPs-enriched emulsions.

  9. PLGA microdevices for retinoids sustained release produced by supercritical emulsion extraction: continuous versus batch operation layouts.

    Science.gov (United States)

    Porta, Giovanna Della; Campardelli, Roberta; Falco, Nunzia; Reverchon, Ernesto

    2011-10-01

    Retinyl acetate (RA) was selected as a model compound to be entrapped in poly(lactic-co-glycolic)acid (PLGA) microspheres using supercritical emulsion extraction (SEE). Several oil-in-water emulsions prepared using acetone and aqueous glycerol (80% glycerol, 20% water) were processed using supercritical carbon dioxide (SC-CO2 ) to extract the oily phase and to induce microspheres formation. The characteristics of the microspheres obtained by conventional liquid emulsion extraction and SEE were also compared: SEE produced spherical and free flowing microspheres, whereas the conventional liquid-liquid extraction showed large intraparticles aggregation. Emulsion extraction by SC-CO2 technology was tested using two different operation layouts: batch (SEE-B) and continuous (SEE-C). SEE-C was performed using a packed tower to produce emulsion/SC-CO2 contact in countercurrent mode, allowing higher microsphere recovery and process efficiencies. Operating at 80 bar and 36°C, SEE-C produced PLGA/RA microspheres with mean sizes between 3.3 and 4.5 μm with an excellent encapsulation efficiency of 80%-90%. Almost all the drug was released in about 6 days when charged at 2.7% (w/w), whereas only 40% and 10% of RA were released in the same period of time when the charge was 5.2% and 8.8% (w/w), respectively. Release kinetics constants calculated from the experimental data, using a mathematical model, were also proposed and discussed. Copyright © 2011 Wiley-Liss, Inc.

  10. Rheology essentials of cosmetic and food emulsions

    CERN Document Server

    Brummer, Rüdiger

    2006-01-01

    Cosmetic emulsions exist today in many forms for a wide variety of applications, including face and hand creams for normal, dry or oily skin, body milks and lotions, as well as sun-block products. Keeping track of them and their properties is not always easy despite informative product names or partial names (e.g. hand or face cream) that clearly indicate their use and properties. This practical manual provides a detailed overview that describes the key properties and explains how to measure them using modern techniques. Written by an expert in flows and flow properties, it focuses on the application of rheological (flow) measurements to cosmetic and food emulsions and the correlation of these results with findings from other tests. Beginning with a brief history of rheology and some fundamental principles, the manual describes in detail the use of modern viscometers and rheometers, including concise explanations of the different available instruments. But the focus remains on practical everyday lab procedure...

  11. Motivation, Induction, and Challenge: Examining the Initial Phase of International Students' Educational Sojourn

    Science.gov (United States)

    Cowley, Paul; Hyams-Ssekasi, Denis

    2018-01-01

    This study explores the initial higher education experiences of first-year international students in the United Kingdom. Questionnaires and semi-structured interviews were carried out with 20 new international students undertaking a business degree at a U.K. university. The students described the key motivating factors for studying abroad and the…

  12. BDD-based reliability evaluation of phased-mission systems with internal/external common-cause failures

    International Nuclear Information System (INIS)

    Xing, Liudong; Levitin, Gregory

    2013-01-01

    Phased-mission systems (PMS) are systems in which multiple non-overlapping phases of operations (or tasks) are accomplished in sequence for a successful mission. Examples of PMS abound in applications such as aerospace, nuclear power, and airborne weapon systems. Reliability analysis of a PMS must consider statistical dependence across different phases as well as dynamics in system configuration, failure criteria, and component behavior. This paper proposes a binary decision diagrams (BDD) based method for the reliability evaluation of non-repairable binary-state PMS with common-cause failures (CCF). CCF are simultaneous failure of multiple system elements, which can be caused by some external factors (e.g., lightning strikes, sudden changes in environment) or by propagated failures originating from some elements within the system. Both the external and internal CCF is considered in this paper. The proposed method is combinatorial, exact, and is applicable to PMS with arbitrary system structures and component failure distributions. An example with different CCF scenarios is analyzed to illustrate the application and advantages of the proposed method. -- Highlights: ► Non-repairable phased-mission systems with common-cause failures are analyzed. ► Common-cause failures caused by internal or external factors are considered. ► A combinatorial algorithm based on binary decision diagrams is suggested

  13. Experimental research of stability of emulsion systems with SIO2 nanoparticles.

    Directory of Open Access Journals (Sweden)

    Zeigman Yury Veniaminovich

    2017-10-01

    Full Text Available Since the beginning of the 21st century scientific research devoted to properties of nanosized particles and their industrial application in the industry of oil and gas fields development has been rapidly evolving. The use of nanosized particles can significantly rise efficiency of technological solutions, and that fact determines this research area as the most promising today. In the area of oil and gas fields development one of the general application for nanoparticles is the development of high-performance technological fluids with new or improved physico-chemical properties. The ability of nanoparticles to modify wettability of the rock surface and to be fixed on the adsorption-solvation stratums of globules makes them a unique tool to regulate physicochemical properties of technological fluids and physical properties of rocks.The article reveals the results of a new stage in the research of physical properties of emulsion systems with silicon dioxide nanoparticles (SiO2. The research carried out within the framework of international project «Development and implementation of water-blocking agents based on the SiO2 nanoparticles application». The results of comparative tests of stability of classical emulsions (O/W and W/O types and emulsion systems modified with SiO2 nanoparticles with different wettability characteristics (hydrophilic or hydrophobic are presented. According to the results of comparative tests, it has been determined that the stability of most samples of modified emulsion systems containing hydrophilic or hydrophobic silica nanoparticles exceeds the stability of classical emulsions by more than 100%. In the course of comparative studies, the following types of experiments were performed: measurement of aggregate stability, electrostability and thermal stability of samples. The paper is a continuation of the complex research which has been published in [1].

  14. Oxidative degradation and non-enzymatic browning due to the interaction between oxidised lipids and primary amine groups in different marine PL emulsions

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline P.

    2012-01-01

    levels of triglycerides in the emulsions. The oxidative and hydrolytic stability of emulsions was investigated through measurement of peroxide value, free fatty acids, and 31P NMR during storage at 2 C for up to 32 days. The oxidative stability of marine PL emulsions during storage was further......Due to the beneficial health effects of marine phospholipids (PL) there is an increasing industrial interest in using them for nutritional applications including emulsified foods. This study was undertaken to investigate both oxidative and hydrolytic stability of marine PL emulsions in relation...... investigated through the measurement of secondary volatile compounds by solid-phase microextraction (SPME) and dynamic headspace (DHS) connected to gas chromatography (GC–MS). Non-enzymatic browning reactions were investigated through the measurement of Strecker derived volatiles, colour changes and pyrrole...

  15. Omega-3s in food emulsions

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte

    2008-01-01

    There is an increasing interest in the use of healthy long chain omega-3 oils in foods. Incorporation of omega-3 oils into foods decreases their oxidative stability and therefore precautions need to be taken to avoid lipid oxidation. This review summarises the major factors to take...... into consideration when developing food emulsions enriched with omega-3 oils and examples on how oxidation can be reduced in products such as mayonnaise, spreads, milk, yoghurt are also given....

  16. Track theory and nuclear photographic emulsions for Dark Matter searches

    International Nuclear Information System (INIS)

    Ditlov, V.A.

    2013-01-01

    This work is devoted to the analysis of possibilities of nuclear emulsions for Dark Matter search, particles of which can produce slow recoil-nuclei. Tracks of such recoil-nuclei in developed nuclear emulsion consist from several emulsion grains. The analysis was carried out with Monte-Carlo calculations made on the basis of the Track Theory and the various factors influencing Dark Matter particles registration efficiency were investigated. Problems, which should be solved for optimal utilization of nuclear emulsions in Dark Matter search, were formulated. B ody - Highlights: ► Specific features of Dark Matter Search in nuclear photographic emulsions. ► Track theory for WIMP search in nuclear emulsions. ► Primary efficiency for single WIMP registration. ► Properties of primary WIMP registration efficiency. ► Primary registration efficiency of WIMP flow

  17. Hydration process for calcium-aluminate cement within EVA emulsion by SPring-8 synchrotron radiation x-ray diffraction method

    International Nuclear Information System (INIS)

    Kotera, Masaru; Matsuda, Ikuyo; Miyashita, Keiko; Adachi, Nobuyuki; Tamura, Hisayuki

    2005-01-01

    Polymer-modified mortars which consist of a polymer emulsion and cement materials have been widely developed in the construction materials fields. Forming process of the polymer-modified cement membrane simultaneously involves evaporation of water within the polymer emulsion and hydration of cement. It is important for the polymer-modified cement paste that the hydrate crystal of cement is generating by the hydration during the setting process under existence of the polymer emulsion. In this study, hydration process for calcium-aluminate cement under existence of poly (ethylene-vinyl acetate) (EVA) emulsion (polymer-cement ratio=100%) was investigated by X-ray diffraction method using synchrotron radiation (SPring-8). The diffraction peaks of calcium aluminate (CA) disappeared after the hardening, on the other hand, the peaks of hydrate crystals of calcium-aluminate cement (C 2 AH 8 and C 3 AH 6 ) could be observed. This polymer-modified cement paste hydrated using the water within the polymer emulsion. The hydration of C 2 AH 8 from CA started at around 300 min, and then C 3 AH 6 hydrate crystal increased after 700 min at ambient temperature. This implies that the conversion from C 2 AH 8 to C 3 AH 6 occurred to be more stable phase. The setting temperature affected the reaction rate. In case of hydration at 35degC, the start time of the hydration for calcium-aluminate cement was quicker than that in the ambient temperature four or more times. (author)

  18. Study of Water-Oil Emulsion Breaking by Stabilized Solution Consisting of Anionic Surface Acting Agent - Soda Ash - Polymer (ASP)

    Science.gov (United States)

    Kulichkov, S. V.; Avtomonov, E. G.; Andreeva, L. V.; Solomennik, S. F.; Nikitina, A. V.

    2018-01-01

    The paper provides a laboratory research of breaking natural water-oil emulsions: - by non-stabilized ASP; by stabilized ASP; by mixture of stabilized and non-stabilized ASP in different proportions and production of refinery water of the required quality with the use of IronGuard 2495 as flocculant. Oil-in-water emulsion is stable. Classic methods are not suitable for residual water treatment: sediment gravity flow; filtration; centrifuge test. Microemulsion formed after ASP application has low boundary tension and high pH. It contributes to transfer of oil phase into a water one, forming oil-in-water emulsion. Alkaline condition has adverse effect on demulsifying ability of agents, flocculation and boundary tension. For breaking of water-oil emulsion at EBU before the interchanger water or water-oil emulsion from the wells that were not APS-treated in ratio of 1:9 shall be delivered. Residual water after EBU must be prepared in water tanks by dilution in great volume.

  19. Lipid oxidation in base algae oil and water-in-algae oil emulsion: Impact of natural antioxidants and emulsifiers.

    Science.gov (United States)

    Chen, Bingcan; Rao, Jiajia; Ding, Yangping; McClements, David Julian; Decker, Eric Andrew

    2016-07-01

    The impact of natural hydrophilic antioxidants, metal chelators, and hydrophilic antioxidant/metal chelator mixture on the oxidative stability of base algae oil and water-in-algae oil emulsion was investigated. The results showed that green tea extract and ascorbic acid had greatest protective effect against algae oil oxidation and generated four day lag phase, whereas rosmarinic acid, grape seed extract, grape seed extract polymer, deferoxamine (DFO), and ethylenediaminetetraacetic acid (EDTA) had no significant protective effect. Besides, there was no synergistic effect observed between natural antioxidants and ascorbic acid. The emulsifiers are critical to the physicochemical stability of water-in-algae oil emulsions. Polyglycerol polyricinoleate (PGPR) promoted the oxidation of emulsion. Conversely, the protective effect on algae oil oxidation was appreciated when defatted soybean lecithin (PC 75) or defatted lyso-lecithin (Lyso-PC) was added. The role of hydrophilic antioxidants in emulsion was similar to that in algae oil except EDTA which demonstrated strong antioxidative effect in emulsion. The results could provide information to build up stable food products containing polyunsaturated fatty acids (PUFA). Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Development and characterization of functional O/W emulsions with chia seed (Salvia hispanicaL.) by-products.

    Science.gov (United States)

    Julio, Luciana Magdalena; Ixtaina, Vanesa Yanet; Fernández, Mariela; Torres Sánchez, Rosa Maria; Nolasco, Susana María; Tomás, Mabel Cristina

    2016-08-01

    The present work investigated the physicochemical properties of O/W emulsions containing functional ingredients (oil with high ω-3 fatty acid content, protein and/or soluble fiber) from chia seeds. The effect of different protein-carbohydrate combinations (sodium caseinate and lactose, sodium caseinate and maltodextrin, chia protein-rich fraction and maltodextrin) and the presence of chia mucilage (0 and 0.2 % wt/wt) in the aqueous phase of chia O/W emulsions was studied as a function of droplet size distribution, Sauter mean diameter, ζ-potential, rheological properties and backscattering profiles. The use of sodium caseinate in combination with lactose or maltodextrin produced chia O/W emulsions with small droplet size (0.22-0.27 µm), high degree of uniformity in droplet size distribution, negatively charged droplets (at pH 6.5), pseudoplastic behavior and high physical stability. Emulsions with chia protein-rich fraction presented wider droplet size distribution and higher D[3,2] values than the previous ones, recording a Newtonian behavior. The addition of chia mucilage affected the physicochemical properties studied, mainly the rheological characteristics of emulsions.

  1. External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

    International Nuclear Information System (INIS)

    Hoennicke, M.G.; Cusatis, C.; Rigon, L.; Menk, R.-H.; Arfelli, F.; Foerster, L.A.; Rosado-Neto, G.H.

    2010-01-01

    Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

  2. External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

    Science.gov (United States)

    Hönnicke, M. G.; Cusatis, C.; Rigon, L.; Menk, R.-H.; Arfelli, F.; Foerster, L. A.; Rosado-Neto, G. H.

    2010-08-01

    Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures ( Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

  3. External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hoennicke, M.G., E-mail: mhonnicke@bnl.go [NSLS II, Brookhaven National Laboratory, Upton, NY (United States); Cusatis, C. [LORXI, Departamento de Fisica-UFPR, Curitiba (Brazil); Rigon, L. [Instituto Nazionale di Fisica Nucleare, Trieste (Italy); Menk, R.-H. [Sincrotrone Trieste SCPa, Basovizza, Trieste (Italy); Arfelli, F. [Instituto Nazionale di Fisica Nucleare, Trieste (Italy); Dipartamento di Fisica-Universita di Trieste, Trieste (Italy); Foerster, L.A.; Rosado-Neto, G.H. [Departamento de Zoologia-UFPR, Curitiba (Brazil)

    2010-08-21

    Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

  4. [Multiple emulsions; bioactive compounds and functional foods].

    Science.gov (United States)

    Jiménez-Colmenero, Francisco

    2013-01-01

    The continued appearance of scientific evidence about the role of diet and/or its components in health and wellness, has favored the emergence of functional foods which currently constitute one of the chief factors driving the development of new products. The application of multiple emulsions opens new possibilities in the design and development of functional foods. Multiple emulsions can be used as an intermediate product (food ingredient) into technological strategies normally used in the optimization of the presence of bioactive compounds in healthy and functional foods. This paper presents a summary of the types, characteristics and formation of multiple emulsions, possible location of bioactive compounds and their potential application in the design and preparation of healthy and functional foods. Such applications are manifested particularly relevant in relation to quantitative and qualitative aspects of lipid material (reduced fat/calories and optimization of fatty acid profile), encapsulation of bioactive compounds mainly hydrophilic and sodium reduction. This strategy offers interesting possibilities regarding masking flavours and improving sensory characteristics of foods. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

  5. A Study of the behaviour of emulsion explosives

    OpenAIRE

    Allum, J

    2009-01-01

    This study investigated the formulation and characterisation of emulsion explosives. This included the manufacture of more than 120kg of emulsion explosive of which around 105kg was used on the explosive ordnance range in over 350 individual firings. For each emulsion composition, an average of eight firings was undertaken with which to substantiate the explosive performance data. The formulation was varied to determine the effects of water content upon the physical characte...

  6. Effect of primary emulsions on microsphere size and protein-loading in the double emulsion process.

    Science.gov (United States)

    Maa, Y F; Hsu, C C

    1997-01-01

    Incorporation of a protein drug in microspheres made of a hydrophobic polymer is commonly achieved via double liquid-liquid emulsification (w/o/w) or by dispersing a powdered protein in a polymer solution followed by liquid-liquid emulsification (s/o/w). This study focused on the effect of the first operating step in both processes on the size and protein-loading of the microspheres. Bovine serum albumin (BSA) was used as the model protein and poly(methyl methacrylate) (PMMA) was used as the model polymer. The w/o emulsion was characterized based on the degree of emulsion fineness which was controlled using rotor/stator homogenization. The s/o emulsion was characterized based on protein powder size and shape. Protein powders of different sizes and shapes were produced using different powder preparation methods. In both emulsification processes, the second operating step which produced the microspheres was conducted in either a continuously stirred tank reactor (CSTR) or a static mixer. The size of the microspheres thus prepared was found to increase with increasing size of the protein powder in the s/o/w system but increase with decreasing size of the liquid emulsion droplets in the w/o/w system. Empirical correlations can accurately predict the size of the microspheres if the size of w/o emulsion droplets and protein powder is 10 x less than the microsphere size. Protein loading in the microspheres decreased with respect to increases in w/o emulsion droplet size or in protein powder size. We propose that these phenomena are attributed to two mechanisms, fragmentation along the weak routes in the w/o/w system and particle redistribution as the result of terminal velocity in the s/o/w system. The role of protein powder shape was not significant until the protein powder size exceeded 5 microns. Irregular-shaped protein powders resulted in lower encapsulation efficiency than spherical-shaped protein powders.

  7. Oxidative enzymatic gelation of sugar beet pectin for emulsion stabilization

    DEFF Research Database (Denmark)

    Abang Zaidel, Dayang Norulfairuz; Meyer, Anne S.

    2013-01-01

    Pectin from sugar beet is derived from the sugar beet pulp residue which results when sugar beets are processed for sucrose extraction. The sugar beet pectin has poor gelationability by the classic divalentcation molecular mechanism because of a relatively high acetylation degree and short...... emulsions has recently been investigated in model food emulsions. This paper reviews the pectin chemistry, enzymatic oxidative gelation mechanisms, interaction mechanisms of the sugar beet pectin with the emulsion droplets and explores how the gelation affects the rheology and stability of emulsion systems...

  8. Mathematical Approach in Rheological Characterizing of Asphalt Emulsion Residues

    Directory of Open Access Journals (Sweden)

    Seong Hwan Cho

    2015-01-01

    Full Text Available Three different emulsion residues, such as SS1HP, HFE90, and SS-1VH (trackless, and a base asphalt binder (PG 64-22 are compared to characterize rheological properties by using DSR test. In order to capture the emulsion properties, different frequencies (from 1 to 100 rad/sec at a 10% constant shear rate and temperatures (from −45°C to 75°C with 15°C increments were applied. Then, a master curve for shear modulus was plotted for each emulsion. The transition of the HFE90 emulsion from viscous to elastic behavior occurs at lower temperatures, compared to the other materials. This emulsion is known for performing in a wider temperature range as shown in the results. The trackless emulsion presents an elastic behavior at intermediate temperatures. This product is known as having very fast setting and high resistance to shear stresses. The trackless emulsion presents the highest viscous and elastic modulus, followed by the PG 64-22 binder, SS1HP, and HFE90 emulsion. Shear strength test results show a behavior between trackless emulsion and SS1HP similar to the frequency sweep test results performed by DSR.

  9. Laboratory effectiveness testing of water-in-oil emulsion breakers

    International Nuclear Information System (INIS)

    Fingas, M.F.; Fieldhouse, B.; Bier, I.; Conrod, D.; Tennyson, E.

    1995-01-01

    The physics and chemistry of water-in-oil emulsions dominate the development of effectiveness tests. Emulsions are variable in stability--this variability is largely dependent on oil type and degree of weathering. These factors complicate the development of a test. Emulsions which have low stability will apparently break easily with chemical emulsion breakers. Broken emulsions will form a foam-like material, called rag, which retains water which is not part of the stable emulsions. Analytical methods used to determine the final stability of the broken or unbroken emulsion were evaluated. Measurements of water content and viscosity measurements show correlation to emulsion stability. Viscosity provides a more reliable measure of emulsion stability but water content measurements are more convenient and are largely used in this study. Twelve tests were developed in the past. Two testing methods have been developed to a usable stage. These tests are described and data using them provided. The effects of mixing time, agent amount, settling time and mixing energy on effectiveness results are presented

  10. Tweens demulsification effects on heavy crude oil/water emulsion

    Directory of Open Access Journals (Sweden)

    Nastaran Hayati Roodbari

    2016-09-01

    Full Text Available The demulsification role of Tweens (nonionic polymers was determined in the separation of water from heavy crude oil emulsion. According to the previous researches, these nonionic polymers, having hydrophilic and lipophilic groups, are appropriate for making oil in water emulsion. In this research their effects in certain concentrations on demulsifying of water in crude oil emulsion were proved. High molecular weight, alkenes’ chains and groups of ketone and ester in these polymers can improve their performance for the demulsification of water in crude oil emulsion. Their efficiencies are improved with electronegative groups such as oxygen. They leave no corrosion effect because they are neutral and do not leave counter ions.

  11. Liquid-liquid phase separation in internally mixed magnesium sulfate/glutaric acid particles

    Science.gov (United States)

    Wu, Feng-Min; Wang, Xiao-Wei; Jing, Bo; Zhang, Yun-Hong; Ge, Mao-Fa

    2018-04-01

    The confocal Raman microscopy is utilized to investigate the liquid-liquid phase separation (LLPS) of mixed magnesium sulfate/glutaric acid (MgSO4/GA) droplets deposited on a hydrophobic polytetrafluoroethylene (PTFE) substrate and a hydrophilic quartz substrate. Raman spectra collected from different regions of the mixed droplets provide detailed information of component distributions for MgSO4 and GA. During the dehydration process, the MgSO4/GA mixed particles show the initial liquid-liquid phase separation between 85% and 80% relative humidity (RH) on both the hydrophobic and hydrophilic substrates. For the droplets deposited on the two substrates, the inner phase of droplets is dominated by aqueous MgSO4, which is surrounded by a rich GA organic layer due to the surface tension effects. In addition, the crystallization of GA could be observed in the organic aqueous phase while it is inhibited in the inner MgSO4 phase due to the effects of gel formation of MgSO4 at low RH. The Raman spectra reveal that with decreasing RH the morphology of the mixed droplet evolves from a uniform droplet to the structure of LLPS with the GA crystallizing in the outer layer and MgSO4 gel formed in the inner phase. These findings contribute to the further understanding of the role of interactions between inorganic salts and organic acids on the morphological evolution and environmental effects of atmospheric aerosols under ambient RH conditions.

  12. Polyimide Nanocomposite Circuit Board Materials to Mitigate Internal Electrostatic Discharge, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — In Sub-topic T8.02, NASA has identified a need for improved circuit boards to mitigate the hazards of internal electrostatic discharge (IESD) on missions where high...

  13. Study on frictional pressure drop of steam-water two phase flow in optimized four-head internal-ribbed tube

    International Nuclear Information System (INIS)

    Wang Weishu; Zhu Xiaojing; Bi Qincheng; Wu Gang; Yu Shuiqing

    2012-01-01

    The optimized internal-ribbed tube is different from the normal internal-ribbed tube on the frictional pressure drop characteristics. The frictional pressure drop characteristics of steam-water two phase flow in horizontal four-head optimized internal-ribbed were studied under adiabatic condition. According to the experimental and calculation results, the two-phase multiplier is greatly affected by the steam quality and pressure. The two-phase multiplier increases with increasing quality, and decreases with increasing pressure. In the near-critical pressure region, the two-phase multiplier is close to 1. The frictional pressure drop of two phase flow in optimized tube is less than that in the normal tube under the same work condition. The good hydrodynamic condition could be achieved when the optimized internal-ribbed tube is used in the heat transfer equipment because the self-compensating characteristics exist due to the reduction of frictional pressure drop. (authors)

  14. Assessing Interactions between Lipophilic and Hydrophilic Antioxidants in Food Emulsions.

    Science.gov (United States)

    Durand, Erwann; Zhao, Yu; Coupland, John N; Elias, Ryan J

    2015-12-16

    Dietary lipids containing high concentrations of polyunsaturated fatty acids are considered to be beneficial to human health, yet their incorporation within formulated foods is complicated by their susceptibility to oxidation. Lipid oxidation in foods is inhibited through the incorporation of antioxidants, yet the list of antioxidants approved for food use is small, and consumers frequently demand foods without synthetic additives. As a consequence, food processors are now tasked with improving the efficacy of approved, "natural" (i.e., nonsynthetic) antioxidants; a rational strategy for doing so involves localizing the antioxidants at the interface where oxidation usually occurs and regenerating the consumed antioxidants after the oxidation event has occurred. The present study describes a procedure to evaluate antioxidant interactions in oil-in-water food emulsions, which is based on controlled oxidation reactions induced in the dispersed oil phase by the lipophilic radical generator, 2,2'-azobis(2,4-dimethylvaleronitrile). The extent of lipid oxidation is measured spectroscopically by following the loss of an oxidatively labile, lipophilic probe (methyl eleostearate), the synthesis of which is described here. Using this procedure, the ability of various aqueous phase solvated antioxidants (ascorbic acid, gallic acid, (-)-epicatechin, (-)-epigallocatechin-3-gallate) to regenerate lipid phase solvated α-tocopherol was evaluated. In all cases, the test compounds were able to inhibit oxidation reactions; however, these effects were not profoundly synergistic, and the maximum synergistic interaction observed was only ∼ 3% using ascorbic acid.

  15. Innovative precipitation in emulsion process: toward a non-nuclear industrial application

    International Nuclear Information System (INIS)

    Ollivier, M.; Borda, G.; Charton, S.; Flouret, J.

    2016-01-01

    A precipitation in emulsion process has been proposed by Borda et al. in 2008 for the continuous precipitation of lanthanides or actinides as oxalate, in order to either increase the production capacity or allow the precipitation of long-life radioactive elements under optimum safety conditions. During research/development tests, a strong correlation between the emulsion's properties and those of the particles produced have been evidenced, thus enabling the size and morphology of the powder to be tuned by varying the droplets properties, the latter being controlled by the column operating conditions. This process thus appears as an attractive alternative to conventional processes for the synthesis of high-value precipitates; as it offers interesting intensification capabilities. In this context, the feasibility of the precipitation of bismuth subnitrate (BSN), for which the emulsion route for precipitation seems to be particularly attractive, has been studied. Indeed, the division of the reacting volume into droplets may allow efficient temperature regulation of the exothermic reaction. In addition, an improvement of the product appearance is expected. This first phase of the feasibility study focused on the choice of the organic phase and the sensitivity of the droplets and solid particles properties to the operating conditions. Following the encouraging results observed in stirred-tank reactor, we successfully tested the implementation in a pulsed column, at lab-scale. (authors)

  16. Study of the Leacril Dyeing Process by a Cationic Dye from an Emulsion System.

    Science.gov (United States)

    Chibowski, E.; Ortega, A. Ontiveros; Espinosa-Jiménez, M.; Perea-Carpio, R.; Holysz, L.

    2001-03-15

    Adsorption studies of a cationic dye, Rhodamine B, from an emulsion phase on Leacril fabric at different temperatures were conducted. The emulsion phase consisted of n-hexadecane emulsified by isopropyl alcohol (1 M) and stabilized by tannic acid. In the alcohol solution Rhodamine B was dissolved. The kinetics of its adsorption and desorption is discussed. The changes in Leacril surface free energy components in the dyeing process were also determined. The adsorption data show that the presence of an emulsion increases the dye adsorption at room temperature (293 K) and at 313 K, while at 333 K it is smaller than that from Rhodamine solution alone. However, Rhodamine desorbs more when adsorbed from the solution. Surface free energy components differ for the Leacril samples dyed at different temperatures, and the most hydrophobic surface was obtained for the samples dyed at 333 K, where the electron-donor component is the lowest one. In general, the work of water spreading is close to zero, except for the above sample for which it is relatively highly negative. Possible mechanisms of the dye adsorption are discussed. Copyright 2001 Academic Press.

  17. Water-in-Water Emulsion Based Synthesis of Hydrogel Nanospheres with Tunable Release Kinetics

    Science.gov (United States)

    Aydın, Derya; Kızılel, Seda

    2017-07-01

    Poly(ethylene glycol) (PEG) micro/nanospheres have several unique advantages as polymer based drug delivery systems (DDS) such as tunable size, large surface area to volume ratio, and colloidal stability. Emulsification is one of the widely used methods for facile synthesis of micro/nanospheres. Two-phase aqueous system based on polymer-polymer immiscibility is a novel approach for preparation of water-in-water (w/w) emulsions. This method is promising for the synthesis of PEG micro/nanospheres for biological systems, since the emulsion is aqueous and do not require organic solvents or surfactants. Here, we report the synthesis of nano-scale PEG hydrogel particles using w/w emulsions using phase separation of dextran and PEG prepolymer. Dynamic light scattering (DLS) and scaning electron microscopy (SEM) results demonstrated that nano-scale hydrogel spheres could be obtained with this approach. We investigated the release kinetics of a model drug, pregabalin (PGB) from PEG nanospheres and demonstrated the influence of polymerization conditions on loading and release of the drug as well as the morphology and size distribution of PEG nanospheres. The experimental drug release data was fitted to a stretched exponential function which suggested high correlation with experimental results to predict half-time and drug release rates from the model equation. The biocompatibility of nanospheres on human dermal fibroblasts using cell-survival assay suggested that PEG nanospheres with altered concentrations are non-toxic, and can be considered for controlled drug/molecule delivery.

  18. Innovative precipitation in emulsion process: toward a non-nuclear industrial application

    Energy Technology Data Exchange (ETDEWEB)

    Ollivier, M.; Borda, G.; Charton, S. [CEA, Centre de Marcoule, DEN,DTEC,SGCS, F-30207 Bagnols-sur-Ceze (France); Flouret, J. [OCM, ZI Quai Jean Jaures, 197 Avenue Marie Curie, 07800 La Voulte-sur-Rhone (France)

    2016-07-01

    A precipitation in emulsion process has been proposed by Borda et al. in 2008 for the continuous precipitation of lanthanides or actinides as oxalate, in order to either increase the production capacity or allow the precipitation of long-life radioactive elements under optimum safety conditions. During research/development tests, a strong correlation between the emulsion's properties and those of the particles produced have been evidenced, thus enabling the size and morphology of the powder to be tuned by varying the droplets properties, the latter being controlled by the column operating conditions. This process thus appears as an attractive alternative to conventional processes for the synthesis of high-value precipitates; as it offers interesting intensification capabilities. In this context, the feasibility of the precipitation of bismuth subnitrate (BSN), for which the emulsion route for precipitation seems to be particularly attractive, has been studied. Indeed, the division of the reacting volume into droplets may allow efficient temperature regulation of the exothermic reaction. In addition, an improvement of the product appearance is expected. This first phase of the feasibility study focused on the choice of the organic phase and the sensitivity of the droplets and solid particles properties to the operating conditions. Following the encouraging results observed in stirred-tank reactor, we successfully tested the implementation in a pulsed column, at lab-scale. (authors)

  19. Effective and Reversible Switching of Emulsions by an Acid/Base-Mediated Redox Reaction.

    Science.gov (United States)

    Zhang, Yuandi; Chen, Hui; Liu, Xuefeng; Zhang, Yongmin; Fang, Yun; Qin, Zhirong

    2016-12-27

    To develop a fast, effective, and reversible strategy for phase separation and re-emulsification of the surfactant-based emulsions, a strategy for using acid/base-mediated redox reactions was established to switch the emulsions formed from a redox-responsive anionic surfactant of potassium dodecyl seleninate (C 12 SeO 2 K). Upon acidification, C 12 SeO 2 K was reduced by KI to give didodecyl diselenide (C 12 Se) 2 , a state of almost no surface or interfacial activity; upon basification, (C 12 Se) 2 was oxidized by I 2 to give C 12 SeO 2 K again. The fractional conversion of C 12 SeO 2 K in the reversible switching processes was close to 100%. Consequently, an unusually large change in interfacial tension (ΔIFT) as high as ∼27.1 mN m -1 was obtained at a wider concentration range starting from the critical micelle concentration of C 12 SeO 2 K; the highest IFT at the oil-water interface was obtained after an almost complete switch-off, giving an oil-aqueous solution interface very similar to that without any emulsifiers, which leads to the effective and fast phase separation of the C 12 SeO 2 K-based switchable emulsions.

  20. Study on phase transformations in superconducting Ti-50%Nb alloy using temperature-dependent internal friction method

    International Nuclear Information System (INIS)

    Shapoval, B.I.; Tikhinskij, G.F.; Somov, A.I.; Chernyj, O.V.; Rudycheva, T.Yu.; Andrievskaya, N.F.

    1980-01-01

    The internal friction method is used to study phase transformations in the Ti-50%Nb alloy parallel with other methods. The effect of annealing temperature and time, as well as the content of interstitial impurities in the alloy and its thermomechanical treatment (TMT) is studied. In the 250-300 deg C temperature range the complex maximum of internal friction caused by extraction of secondary phases is observed. The latter is confirmed by the measurement data of mechanical properties and electron microscopic analysis. The maximum consists of three overlapping peaks that reflects stepped form of the decomposition process of the metastable solid solution. The preliminary thermo-mechanical alloy treatment consisting of equidirectional plastic deformation with the following recrystallization annealing leads to peak increase. This fact testifies to the stimulating effect of thermo-mechanical treatment on the degree of solid solution decomposition and reveals in the increase of the critical current density of a wire made of the ingot. The increase of the interstitial impurity content in the alloy has the analogous effect. The reduction of the internal friction level during isothermal stand-up at temperatures higher than the third peak temperature proceeds in two stages [ru

  1. Development and evaluation of an emulsion containing lycopene for combating acceleration of skin aging

    Directory of Open Access Journals (Sweden)

    Letícia Caramori Cefali

    2015-09-01

    Full Text Available Lycopene, a carotenoid and potent antioxidant is found in large quantities in tomatoes. Lycopene combats diseases, such as cardiovascular disease and different types of cancer, including prostate cancer. However, its topical use in emulsion form for the combat of skin aging is under-explored. The aim of the present study was to develop an emulsion containing lycopene extracted from salad tomatoes and evaluate its cytotoxicity, stability, rheological behavior, antioxidant activity and phytocosmetic permeation. The developed cosmetic comprised an oil phase made up of shea derivatives and was evaluated in terms of its physiochemical stability, spreadability, thermal analysis, rheological behavior, microbiological quality, cytotoxicity, antioxidant activity, cutaneous permeation and retention. The results demonstrate that this phytocosmetic is stable, exhibits satisfactory rheological behavior for a topical formula and is a promising product for combating skin aging.

  2. Preparation, characterization and in vitro intestinal absorption of a dry emulsion formulation containing atorvastatin calcium.

    Science.gov (United States)

    Yin, Yong-Mei; Cui, Fu-De; Kim, Jung Sun; Choi, Min-Koo; Choi, Byung Chul; Chung, Suk-Jae; Shim, Chang-Koo; Kim, Dae-Duk

    2009-01-01

    A redispersible dry emulsion (DE) formulation of atorvastatin calcium (AC) was developed to enhance the in vitro dissolution of AC, thereby increasing its gastrointestinal absorption. The spray-drying technology was used where Plurol Oleique CC 497 was chosen as the oil phase. Effects of carriers, surfactants, and homogenizers on the characteristics of DE containing AC were systematically investigated. The final formulation consisted of dextrin and Poloxamer 188 as carrier and surfactant, respectively, and was homogenized by a high pressure homogenizer before spray drying. The in vitro release of AC from the optimized DE was significantly higher than that of pure AC powder (76% vs. 30% at 24 hr). The in vitro intestinal absorption of AC from the DE formulation was 0.77 microg/cm(2) at 2 hr, which was a 2.33-fold increase compared to the pure unformulated AC powder. These results suggest that the oral dry emulsion formulation could improve the intestinal absorption of AC.

  3. Research advances in polymer emulsion based on "core-shell" structure particle design.

    Science.gov (United States)

    Ma, Jian-zhong; Liu, Yi-hong; Bao, Yan; Liu, Jun-li; Zhang, Jing

    2013-09-01

    In recent years, quite many studies on polymer emulsions with unique core-shell structure have emerged at the frontier between material chemistry and many other fields because of their singular morphology, properties and wide range of potential applications. Organic substance as a coating material onto either inorganic or organic internal core materials promises an unparalleled opportunity for enhancement of final functions through rational designs. This contribution provides a brief overview of recent progress in the synthesis, characterization, and applications of both inorganic-organic and organic-organic polymer emulsions with core-shell structure. In addition, future research trends in polymer composites with core-shell structure are also discussed in this review. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Modeling of gadolinium recovery from nitrate medium with 8-hydroxyquinoline by emulsion liquid membrane

    International Nuclear Information System (INIS)

    Hasan, M.A.; Aglan, R.F.; El-Reefy, S.A.

    2009-01-01

    The extraction equilibrium of Gd(III) from nitrate medium by 8-hydroxyquinoline (HOX) in toluene was studied. Liquid-liquid investigations were first carried out. Based on the equilibrium results, the extraction of Gd(III) from aqueous nitrate medium into an emulsion liquid membrane system (ELM) containing 8-hydroxyquinoline in toluene as extractant, HNO 3 as stripping solution, Span-80 as surfactant was studied. The stability of the prepared ELM was studied in terms of the degree of membrane breakage. The different parameters affecting the permeation of gadolinium (III) were also studied. A general permeation model for the recovery of Gd(III) by the selected membrane is presented. The internal mass transfer in the water in oil (W/O) emulsion drop, the external mass transfer around the drop, the rates of formation and decomposition of the complex at the external aqueous-organic interface were considered.

  5. Textural perception of liquid emulsions: Role of oil content, oil viscosity and emulsion viscosity

    NARCIS (Netherlands)

    Aken, van G.A.; Vingerhoeds, M.H.; Wijk, de R.A.

    2011-01-01

    This work describes a study on the in-mouth textural perception of thickened liquid oil-in-water emulsions. The variables studied are oil content, oil viscosity, and the concentration of polysaccharide thickener. Gum arabic was chosen as the thickener because of the nearly Newtonian behavior of its

  6. Ultra structure of oil-in-water emulsions a comparison of different microscopy- and preparation methods

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Loussert, C.; Humbel, B.M.

    We compare chemical fixation/ room temperature embedding in resin, cryofixation/ freeze substitution, and cryofixation/cryo imaging (freeze-fracture cryo-SEM) on several oil-in-water food emulsions. This is for visualization of the structure and thickness of the emulsifying layers consisting...... of this interface and even the protein in the water phase. We observed that freeze substituted material seems to correspond very well to images of freeze fractured frozen samples in cryo-SEM where protein aggregates seems to be visible in the water phase. With this work, we want to demonstrate the importance...

  7. The Influence of Emulgator on Stability of Emulsion H3PO4 in Topo-Kerosene and Efficiency at Emulsion Membrane Extraction of La and Nd Concentrate Product of Monazite Sand Treatment

    International Nuclear Information System (INIS)

    Purwani, MV.; Bintarti, AN.; Subagiono, R.

    2002-01-01

    The making of La and Nd concentrate from monazite sand have been done. The separation of La and Nd by emulsion 1M H 3 PO 4 in 5 % TOPO-Kerosene membrane extraction. The feed or aqueous phase was La and Nd concentrate in 1M HNO 3 . Emulgator Span-80 and Tween-80 were used to stabilize emulsion membrane. The influence parameters were percentage of Span-80 and ratio of Span-80 and Tween-80. After formation of emulsion membrane, the extraction process was carried out. Ratio of volume of feed : volume membrane phase = 1 : 1, ratio of volume of 5% TOPO - Kerosene : ratio of volume of 1M H 3 PO 4 1 : 1. The best yield were obtained time of emulsification was 10 minutes with the speed of emulsion was 6000 rpm and concentration of span-80 was 5%. At this condition was obtained the extraction efficiency of La was 55.55%, the extraction efficiency of Nd was 41.6% the stripping efficiency of La was 35.05%, the stripping efficiency of Nd was 87.32 %, the total efficiency of La was 19.46%, the total efficiency of Nd was 36.30% and Separation factor of Nd and La = 1.87. (author)

  8. Short-coherence in-line phase-shifting infrared digital holographic microscopy for measurement of internal structure in silicon

    Science.gov (United States)

    Xi, Teli; Dou, Jiazhen; Di, Jianglei; Li, Ying; Zhang, Jiwei; Ma, Chaojie; Zhao, Jianlin

    2017-06-01

    Short-coherence in-line phase-shifting digital holographic microscopy based on Michelson interferometer is proposed to measure internal structure in silicon. In the configuration, a short-coherence infrared laser is used as the light source in order to avoid the interference formed by the reference wave and the reflected wave from the front surface of specimen. At the same time, in-line phase-shifting configuration is introduced to overcome the problem of poor resolution and large pixel size of the infrared camera and improve the space bandwidth product of the system. A specimen with staircase structure is measured by using the proposed configuration and the 3D shape distribution are given to verify the effectiveness and accuracy of the method.

  9. The external and internal structures of Amphizoa davidi Lucas (Coleoptera, Amphizoidae), using X-ray phase contrast microtomography.

    Science.gov (United States)

    Li, Dee; Zhang, Kai; Li, Xiaoyan; Zhu, Peiping; Xu, Caifeng; Wu, Ziyu; Zhou, Hongzhang

    2015-05-27

    The Chinese endemic water beetle Amphizoa davidi Lucas, is a rare and endangered species belonging to the monotypic family Amphizoidae (Coleoptera: Adephaga). A study of the external and internal structures of A. davidi is here presented, by using X-ray phase contrast tomography and light microscopy. Morphological details and three dimensional (3D) structures of this species are provided: skeletons, muscles, reproductive organs of male and female, nervous system, alimentary canal and pygidial gland. The reproductive organs of females are compared in two different developmental phases (ages): before copulation without mature ovaries and after copulation with mature ovaries. Such detailed 3D tomographic study based on micro-CT technology may promote our understanding of the detailed morphology in Amphizoidae and Coleoptera in general.

  10. International Comparisons of Foundation Phase Number Domain Mathematics Knowledge and Practice Standards

    Science.gov (United States)

    Human, Anja; van der Walt, Marthie; Posthuma, Barbara

    2015-01-01

    Poor mathematics performance in schools is both a national and an international concern. Teachers ought to be equipped with relevant subject matter knowledge and pedagogical content knowledge as one way to address this problem. However, no mathematics knowledge and practice standards have as yet been defined for the preparation of Foundation Phase…

  11. Connecting Children Internationally for Science Instruction: Using the Internet to Support Learning about Lunar Phases

    Science.gov (United States)

    Smith, Walter S.; Cheon, Jongpil; Jabri, Faiza; Reynolds, Stephen; Zebedi, Amira

    2012-01-01

    This study investigated the effect on children's science understanding of Internet-based instruction in which children from around the world in grades 4 to 8 observed the Moon for several weeks and then shared their lunar data internationally to find global patterns in the Moon's behavior. Students in two American and one Australian class took the…

  12. The International Migration of Population in the Current Phase: Tendencies and Challenges

    Directory of Open Access Journals (Sweden)

    Iurchenko Svitlana O.

    2017-09-01

    Full Text Available The article considers the characteristics of contemporary international migration of population. It has been shown that international migration encompasses all countries over the world and is an important constituent of the globalization of the world-wide economy. Tendencies in the international migration have been described by regions of the world and by type of country. It has been shown that a concentration of international migrants is present in a relatively small number of world countries, while the developed world is more attractive to migrants than the developing countries. The structure of migrants by sex and age has been considered and the most attractive regions for the migration of women and men have been identified. The problems and tendencies of the forced migration of population have been identified. It has been determined that, in many developed countries, the migration inflow of population will increase in importance in the demographic situation. The need to develop a migration policy in the regions of different hierarchical levels and to implement it in practice has been indicated.

  13. Studies of water-in-oil emulsions : testing of emulsion formation in OHMSETT

    International Nuclear Information System (INIS)

    Fingas, M.; Fieldhouse, B.

    2001-01-01

    A study was conducted to determine the stability of water-in-oil emulsions in the OHMSETT tank facility. The results were then compared with previous laboratory studies which suggested that the stability of emulsions can be grouped into four categories, stable, unstable, meso-stable and entrained. It has been determined that entrained emulsions can retain oil by viscous forces long enough for interfacial agents, resins and asphaltenes to stabilize the droplets. This paper also described the difference in viscosity between the 4 categories of emulsion stability. The OHMSETT tests were conducted in two series of one week each. The first series of tests were conducted in July and involved 12 experiments on 2 different types of oils which were placed at varying thicknesses on the water. The second set of tests were conducted in November and involved 12 experiments on 6 oils. The rheological properties of the oils were measured and compared to the same oils undergoing emulsification in the laboratory. The oils and water-in-oil states produced were found to have analogous properties between the laboratory and the first set of tests at the OHMSETT facility. All the oils tested produced entrained water-in-oil states in both the laboratory and the test tank. The energy in the two test conditions was found to be similar, with the OHMSETT emulsions similar to one produced in the laboratory at high energies. The second series of tests at OHMSETT did not result in the expected water in-oil- states. This unexpected result was most likely due to the residual surfactant from an earlier dispersant experiment. The study showed that the conditions for emulsion formation are analogous in the OHMSETT tank and in the laboratory tests. The level of energy is considered to be the major variant. It was concluded that the energy levels between the laboratory mixing experiments and the OHMSETT is similar. It was shown that surfactants left over from dispersant testing inhibited the formation

  14. Electrospraying of water in oil emulsions for thin film coating

    NARCIS (Netherlands)

    Khan, M.K.I.; Maan, A.A.; Schutyser, M.A.I.; Schroën, C.G.P.H.; Boom, R.M.

    2013-01-01

    Electrospraying of water-in-oil emulsions was investigated to produce thin edible barriers. A reproducible model surface was used, namely cellulose membranes of which permeability is well-established. PGPR-based emulsions were stable during electrospraying and produced a fine stable jet spray;

  15. Splenic lipidosis after administration of intravenous fat emulsions.

    Science.gov (United States)

    Forbes, G B

    1978-01-01

    Spleens showing fatty infiltration and necrosis of the pulp were found at necropsy on several patients who had received intravenous fat emulsions during their terminal illnesses. The postmortem findings are described and the clinicopathological correlation is discussed with special reference to the phenomenon of creaming of the emulsion. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:690241

  16. Formulation and stability of topical water in oil emulsion containing ...

    African Journals Online (AJOL)

    Purpose: To formulate the water in oil (W/O) emulsion of corn silk (CS) extract and to evaluate its stability at various storage conditions. Methods: Ethanol CS extract was prepared using maceration (cold) technique. A 4 % CS emulsion was prepared using varying concentrations of liquid paraffin, ABIL EM90 and water.

  17. Tocopherol isoforms in parenteral lipid emulsions and neutrophil activation.

    NARCIS (Netherlands)

    Wanten, G.J.A.; Beunk, J.; Naber, A.H.J.; Swinkels, D.W.

    2002-01-01

    BACKGROUND AND AIMS: Tocopherol is a lipid-soluble anti-oxidant that exists in several isoforms. Patients on total parenteral nutrition depend on lipid emulsions for their tocopherol intake. In the present study, we analysed the content of tocopherol isoforms in various lipid emulsions. We also

  18. Characteristics of disintegration of different emulsion nuclei by ...

    Indian Academy of Sciences (India)

    An analysis of the data based on 924 inelastic interaction events induced by 28 Si nuclei in a nuclear emulsion is presented. The nuclear fragmentation process is studied by analysing the total charge () distribution of the projectile spectators for different emulsion target groups along with the comparison of Monte Carlo ...

  19. Nonionic emulsion-mediated synthesis of zeolite beta

    Indian Academy of Sciences (India)

    Administrator

    taining OP to obtain the emulsion system. Finally, the emulsion system was transferred to Teflon-lined stainless steel autoclaves and crystallized at 413 K for 48 h and then 443 K for 48 h. For comparison, the conventional zeolite beta synthesis was also carried out under the same crystallization conditions. Notably, when the ...

  20. Physical Stability of Whippable Oil-in-Water Emulsions

    DEFF Research Database (Denmark)

    Munk, Merete Bøgelund

    Whippable emulsions based on vegetable fat are increasingly used as replacement for dairy whipping creams. One of the quality criteria of whippable emulsions is that it should be low-viscous prior to whipping, but sudden viscosity increase or even solidification during storage and transport...

  1. Nonionic emulsion-mediated synthesis of zeolite beta

    Indian Academy of Sciences (India)

    Zeolite beta synthesis was first carried out in a newly developed emulsion system containing nonionic polyoxyethylated alkylphenol surfactant, which showed interesting non-conventional features. Compared to the conventional hydrothermal synthesis of zeolite beta, the reported nonionic emulsion system showed a faster ...

  2. Microfluidic production of multiple emulsions and functional microcapsules

    NARCIS (Netherlands)

    Lee, Tae Yong; Choi, Tae Min; Shim, Tae Soup; Frijns, Raoul A.M.; Kim, Shin Hyun

    2016-01-01

    Recent advances in microfluidics have enabled the controlled production of multiple-emulsion drops with onion-like topology. The multiple-emulsion drops possess an intrinsic core-shell geometry, which makes them useful as templates to create microcapsules with a solid membrane. High flexibility

  3. Interplay between Colloids and Interfaces : Emulsions, Foams and Microtubes

    NARCIS (Netherlands)

    de Folter, J.W.J.

    2013-01-01

    The central theme of this thesis is the interplay between colloids and interfaces. The adsorption of colloids at fluid-fluid interfaces is the main topic and covers Chapters 2-6. Pickering emulsions where colloidal particles act as emulsion stabilizers in the absence of surfactants are studied in a

  4. Stability of cosmetic emulsion containing different amount of hemp oil.

    Science.gov (United States)

    Kowalska, M; Ziomek, M; Żbikowska, A

    2015-08-01

    The aim of the study was to determine the optimal conditions, that is the content of hemp oil and time of homogenization to obtain stable dispersion systems. For this purpose, six emulsions were prepared, their stability was examined empirically and the most correctly formulated emulsion composition was determined using a computer simulation. Variable parameters (oil content and homogenization time) were indicated by the optimization software based on Kleeman's method. Physical properties of the synthesized emulsions were studied by numerous techniques involving particle size analysis, optical microscopy, Turbiscan test and viscosity of emulsions. The emulsion containing 50 g of oil and being homogenized for 6 min had the highest stability. Empirically determined parameters proved to be consistent with the results obtained using the computer software. The computer simulation showed that the most stable emulsion should contain from 30 to 50 g of oil and should be homogenized for 2.5-6 min. The computer software based on Kleeman's method proved to be useful for quick optimization of the composition and production parameters of stable emulsion systems. Moreover, obtaining an emulsion system with proper stability justifies further research extended with sensory analysis, which will allow the application of such systems (containing hemp oil, beneficial for skin) in the cosmetic industry. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  5. Nonionic emulsion-mediated synthesis of zeolite beta

    Indian Academy of Sciences (India)

    ... the reported nonionic emulsion system showed a faster nucleation rate. Furthermore, the emulsion system could stabilize the beta product and retarded its further transformation to ZSM-5 even under the high crystallization temperature at 453 K. Additionally, the beta particle size could be tuned by the adoption of different ...

  6. The Emulsion Scanning System of the OPERA experiment

    Science.gov (United States)

    Di Marco, N.; Hamada, K.; Nonoyama, Y.; Opera Collaboration

    2012-08-01

    The target unit of the OPERA detector, the so called brick, is made of lead plates acting as the neutrino target interleaved with nuclear emulsion films acting as trackers with micrometric accuracy. In this paper we report the nuclear emulsion analysis chain, from the confirmation of the electronic detector trigger for the brick tagging to the neutrino interaction vertex location and reconstruction.

  7. The Emulsion Scanning System of the OPERA experiment

    International Nuclear Information System (INIS)

    Di Marco, N.; Hamada, K.; Nonoyama, Y.

    2012-01-01

    The target unit of the OPERA detector, the so called brick, is made of lead plates acting as the neutrino target interleaved with nuclear emulsion films acting as trackers with micrometric accuracy. In this paper we report the nuclear emulsion analysis chain, from the confirmation of the electronic detector trigger for the brick tagging to the neutrino interaction vertex location and reconstruction.

  8. Application of pork fat diacylglycerols in meat emulsions

    DEFF Research Database (Denmark)

    Miklos, Rikke; Xu, Xuebing; Lametsch, Rene

    2011-01-01

    % DAGs. The fat separation decreased from 10.9% to 7.8% when 10% of DAGs were applied and no fat separation was observed for emulsions prepared with 50% and 100% DAGs. Emulsions containing DAGs were more elastic and solid reflected in a significant increase in Young's modulus and the maximum hardness...

  9. Multi-responsive ionic liquid emulsions stabilized by microgels

    NARCIS (Netherlands)

    Monteillet, H.; Workamp, M.; Li, X.; Schuur, Boelo; Kleijn, J.M.; Leermakers, F.; Sprakel, J.

    2014-01-01

    We present a complete toolbox to use responsive ionic liquid (IL) emulsions for extraction purposes. IL emulsions stabilized by responsive microgels are shown to allow rapid extraction and reversible breaking and re-emulsification. Moreover, by using a paramagnetic ionic liquid, droplets can be

  10. Nonionic emulsion-mediated synthesis of zeolite beta

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Zeolite beta synthesis was first carried out in a newly developed emulsion system containing nonionic polyoxyethylated alkylphenol surfactant, which showed interesting non-conventional features. Compared to the conventional hydrothermal synthesis of zeolite beta, the reported nonionic emulsion system showed ...

  11. Stabilization of Model Crude Oil Emulsion using Different ...

    African Journals Online (AJOL)

    As part of an ongoing research into the stability of oil-field emulsions, model oil samples have been utilized to probe the effects of asphaltene interactions on crude oil/water emulsion stability. Asphaltenes were precipitated from treated Ondo State oil sand bitumen with n-hexane in a 40:1 solvent to bitumen ratio which was ...

  12. Physical methods for initiation of emulsion polymerization processes (review)

    International Nuclear Information System (INIS)

    Averko-Antonovich, I.Yu.; Liakumovich, A.G.

    1994-01-01

    The known and widely used methods for initiation of emulsion polymerization by the exposure of aqueous and organic media to ionizing radiation, plasmoichemical, mechanochemcial, and magnetic treatments, are briefly reviewed. The advantages of radiation-induced emulsion polymerization of vinyl monomers, as compared to the other methods, are pointed out

  13. Formation and stability of emulsions made with proteins and peptides

    NARCIS (Netherlands)

    Smulders, P.E.A.

    2000-01-01

    The formation and stabilization of oil-in-water emulsions using well-defined and well-characterized proteins and peptides was studied in order to elucidate the relation between their molecular and functional properties. The emulsions were formed with a high-pressure homogenizer. To study

  14. Pickering Emulsions for Food Applications: Background, Trends, and Challenges

    NARCIS (Netherlands)

    Berton-Carabin, C.C.; Schroën, C.G.P.H.

    2015-01-01

    Particle-stabilized emulsions, also referred to as Pickering emulsions, have garnered exponentially increasing interest in recent years. This has also led to the first food applications, although the number of related publications is still rather low. The involved stabilization mechanisms are

  15. Aqueous polymer emulsions by chemical modifications of thermosetting alternating polyketones

    NARCIS (Netherlands)

    Zhang, Youchun; Broekhuis, A. A.; Picchioni, F.

    2007-01-01

    Aqueous polymer emulsions were prepared by chemical modifications of thermosetting alternating polyketones in a one-pot reaction. Polymeric amines derived from the polyketones can act as polymeric surfactants for the self-emulsification of polyketones. The stability and structure of the emulsions

  16. Development of Octyl Methoxy Cinnamates (OMC/Silicon Dioxide (SiO2 Nanoparticles by Sol-Gel Emulsion Method

    Directory of Open Access Journals (Sweden)

    Pey-Shiuan Wu

    2017-12-01

    Full Text Available Although octyl methoxy cinnamates (OMC is the most used Ultraviolet B (UVB filter in sunscreen, it has poor light stability in emulsion system. In this study, OMC/SiO2 nanoparticles were prepared via sol-gel emulsion method. Tetraethoxy silane (TEOS was used as the silica source to encapsulate OMC. Modification of experimental parameters such as stirring speed of condensation reaction and emulsion condition, pH value of acid-catalyzed, surfactant and different percentage of TEOS and OMC, adding of OMC and surfactant to different phase may affect the particle size, and yield and entrapment efficiency in preparation process of OMC/SiO2 nanoparticles. Concluding all the parameter, we found that when condensation reaction and emulsion conditions are at 1000 rpm, pH 1.5, Span 80/Tween 20, TEOS/OMC ratios 1:1, OMC and surfactants added in oil phase, resulting in smaller particle sizes 476.5 nm, higher yield 95.8%, and higher entrapment efficiency 61.09%. Fourier transform infrared (FTIR analysis demonstrated that OMC/SiO2 nanoparticles were successfully prepared. In vitro release profile supposed that OMC/SiO2 nanoparticles can delay OMC releasing and had 60.83% decreasing of cumulative amount. Therefore, the OMC/SiO2 nanoparticles have the potential to develop as new sunscreen materials in the use for cosmetics field in the future.

  17. Development of Octyl Methoxy Cinnamates (OMC)/Silicon Dioxide (SiO2) Nanoparticles by Sol-Gel Emulsion Method

    Science.gov (United States)

    Wu, Pey-Shiuan; Lee, Yi-Ching; Kuo, Yi-Ching

    2017-01-01

    Although octyl methoxy cinnamates (OMC) is the most used Ultraviolet B (UVB) filter in sunscreen, it has poor light stability in emulsion system. In this study, OMC/SiO2 nanoparticles were prepared via sol-gel emulsion method. Tetraethoxy silane (TEOS) was used as the silica source to encapsulate OMC. Modification of experimental parameters such as stirring speed of condensation reaction and emulsion condition, pH value of acid-catalyzed, surfactant and different percentage of TEOS and OMC, adding of OMC and surfactant to different phase may affect the particle size, and yield and entrapment efficiency in preparation process of OMC/SiO2 nanoparticles. Concluding all the parameter, we found that when condensation reaction and emulsion conditions are at 1000 rpm, pH 1.5, Span 80/Tween 20, TEOS/OMC ratios 1:1, OMC and surfactants added in oil phase, resulting in smaller particle sizes 476.5 nm, higher yield 95.8%, and higher entrapment efficiency 61.09%. Fourier transform infrared (FTIR) analysis demonstrated that OMC/SiO2 nanoparticles were successfully prepared. In vitro release profile supposed that OMC/SiO2 nanoparticles can delay OMC releasing and had 60.83% decreasing of cumulative amount. Therefore, the OMC/SiO2 nanoparticles have the potential to develop as new sunscreen materials in the use for cosmetics field in the future. PMID:29215572

  18. Development of Octyl Methoxy Cinnamates (OMC)/Silicon Dioxide (SiO₂) Nanoparticles by Sol-Gel Emulsion Method.

    Science.gov (United States)

    Wu, Pey-Shiuan; Lee, Yi-Ching; Kuo, Yi-Ching; Lin, Chih-Chien

    2017-12-07

    Although octyl methoxy cinnamates (OMC) is the most used Ultraviolet B (UVB) filter in sunscreen, it has poor light stability in emulsion system. In this study, OMC/SiO₂ nanoparticles were prepared via sol-gel emulsion method. Tetraethoxy silane (TEOS) was used as the silica source to encapsulate OMC. Modification of experimental parameters such as stirring speed of condensation reaction and emulsion condition, pH value of acid-catalyzed, surfactant and different percentage of TEOS and OMC, adding of OMC and surfactant to different phase may affect the particle size, and yield and entrapment efficiency in preparation process of OMC/SiO₂ nanoparticles. Concluding all the parameter, we found that when condensation reaction and emulsion conditions are at 1000 rpm, pH 1.5, Span 80/Tween 20, TEOS/OMC ratios 1:1, OMC and surfactants added in oil phase, resulting in smaller particle sizes 476.5 nm, higher yield 95.8%, and higher entrapment efficiency 61.09%. Fourier transform infrared (FTIR) analysis demonstrated that OMC/SiO₂ nanoparticles were successfully prepared. In vitro release profile supposed that OMC/SiO₂ nanoparticles can delay OMC releasing and had 60.83% decreasing of cumulative amount. Therefore, the OMC/SiO₂ nanoparticles have the potential to develop as new sunscreen materials in the use for cosmetics field in the future.

  19. International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Ghana. Draft

    International Nuclear Information System (INIS)

    Guelpa, Jean-Paul; Vogel, Wolfram

    1982-12-01

    The Republic of Ghana has no claimed uranium resources in the categories Reasonably Assured and Estimated Additional. The only occurrences known are within pegmatites and are of no economic importance. The IUREP Orientation Phase Mission to Ghana estimates that the Speculative Resources of the country fall between 15,000 and 40,000 tonnes uranium. The IUREP Orientation Phase Mission to Ghana believes that the Panafrican Mobile Belt has the highest uranium potential of all geological units of the country. The Obosum beds are the priority number two target. A three years exploration programme is recommended for a total cost of US $ 5,000,000. The Ghana Atomic Energy Commission and the Ghana Geological Survey provide a basic infrastructure for uranium exploration. Any future uranium development in Ghana should be embedded in a well defined national uranium policy. It is recommended that such a policy be draw, up by the Ghanaian authorities

  20. PHYSICAL AND CHEMICAL STABILITY ANALYSIS OF COSMETIC MULTI- PLE EMULSIONS LOADED WITH ASCORBYL PALMITATE AND SODIUM ASCORBYL PHOSPHATE SALTS.

    Science.gov (United States)

    Khan, Hira; Akhtar, Naveed; Ali, Atif; Khan, Haji M Shoaib; Sohail, Muhammad; Naeem, Muhammad; Nawaz, Zarqa

    2016-09-01

    Stability of hydrophilic and lipophilic vitamin C derivatives for quenching synergistic antioxidant activities and to treat oxidative related diseases is a major issue. This study was aimed to encapsulate hydrophilic and lipophilic vitamin C derivatives (ascorbyl palmitate and sodium ascorbyl phosphate) as functional ingredients in a newly formulated multiple emulsion of the W//W type to attain the synergistic antioxidant effects and the resultant system's long term physical and chemical stability. Several multiple emulsions using the same concentration of emulsifiers but different concentrations of ascorbyl palmitate and sodium ascorbyl phosphate were developed. Three finally selected multiple emulsions (ME₁, ME₂ and ME₃) were evaluated for physical stability in terms of rheology, microscopy, conductivity, pH, and organoleptic characteristics under different storage conditions for 3 months. Chemical stability was determined by HPLC on Sykam GmbH HPLC system (Germany), equipped with a variable UV detector. Results showed that at accelerated storage conditions all the three multiple emulsions had shear thinning behavior of varying shear stress with no influence of location of functional ingredients in a carrier system. Conductivity values increased and pH values remained within the skin pH range for 3 months. Microscopic analysis showed an increase in globule size with the passage of time, especially at higher temperatures while decreased at low temperatures. Centrifugation test did not cause phase separation till the 45th day, but little effects after 2 months. Chemical stability analysis by HPLC at the end of 3 months showed that ascorbyl palmitate and sodium ascorbyl phosphate were almost stable in all multiple emulsions with no influence of their location in a carrier system. Multiple emulsions were found a stable carrier for hydrophilic and lipophilic vitamin C derivatives to enhance their desired effects. Considering that many topical formulations

  1. Pickering emulsions for food applications: background, trends, and challenges.

    Science.gov (United States)

    Berton-Carabin, Claire C; Schroën, Karin

    2015-01-01

    Particle-stabilized emulsions, also referred to as Pickering emulsions, have garnered exponentially increasing interest in recent years. This has also led to the first food applications, although the number of related publications is still rather low. The involved stabilization mechanisms are fundamentally different as compared to conventional emulsifiers, which can be an asset in terms of emulsion stability. Even though most of the research on Pickering emulsions has been conducted on model systems, with inorganic solid particles, recent progress has been made on the utilization of food-grade or food-compatible organic particles for this purpose. This review reports the latest advances in that respect, including technical challenges, and discusses the potential benefits and drawbacks of using Pickering emulsions for food applications, as an alternative to conventional emulsifier-based systems.

  2. Electrochemical-thermal modeling and microscale phase change for passive internal thermal management of lithium ion batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Thomas F. (Georgia Institute of Technology, Atlanta, GA); Bandhauer, Todd (Georgia Institute of Technology, Atlanta, GA); Garimella, Srinivas (Georgia Institute of Technology, Atlanta, GA)

    2012-01-01

    A fully coupled electrochemical and thermal model for lithium-ion batteries is developed to investigate the impact of different thermal management strategies on battery performance. In contrast to previous modeling efforts focused either exclusively on particle electrochemistry on the one hand or overall vehicle simulations on the other, the present work predicts local electrochemical reaction rates using temperature-dependent data on commercially available batteries designed for high rates (C/LiFePO{sub 4}) in a computationally efficient manner. Simulation results show that conventional external cooling systems for these batteries, which have a low composite thermal conductivity ({approx}1 W/m-K), cause either large temperature rises or internal temperature gradients. Thus, a novel, passive internal cooling system that uses heat removal through liquid-vapor phase change is developed. Although there have been prior investigations of phase change at the microscales, fluid flow at the conditions expected here is not well understood. A first-principles based cooling system performance model is developed and validated experimentally, and is integrated into the coupled electrochemical-thermal model for assessment of performance improvement relative to conventional thermal management strategies. The proposed cooling system passively removes heat almost isothermally with negligible thermal resistances between the heat source and cooling fluid. Thus, the minimization of peak temperatures and gradients within batteries allow increased power and energy densities unencumbered by thermal limitations.

  3. The International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three: a global synthesis.

    Science.gov (United States)

    Mallol, J; Crane, J; von Mutius, E; Odhiambo, J; Keil, U; Stewart, A

    2013-01-01

    This ISAAC Phase Three synthesis provides summarised information on the main findings of the study, regional tables and figures related to the prevalence and severity of current symptoms of asthma, rhinoconjunctivitis and eczema in the main regions of the world. The large number of surveyed children (≈1,200,000), the large number of centres (233) and countries (98) that participated in ISAAC Phase Three makes this study the most comprehensive survey of these diseases ever undertaken. Globally, the prevalence for current asthma, rhinoconjunctivitis and eczema in the 13-14-year age group was 14.1%, 14.6% and 7.3%, respectively. In the 6-7-year age group the prevalence for current asthma, rhinoconjunctivitis and eczema was 11.7%, 8.5% and 7.9%, respectively. The study shows a wide variability in the prevalence and severity of asthma, rhinoconjunctivitis and eczema which occurs not just between regions and countries but between centres in the same country and centres in the same city. This study definitively establishes that the prevalence of those diseases can be very high in non-affluent centres with low socioeconomic conditions. The large variability also suggests a crucial role of local environment characteristics to determine the differences in prevalence between one place and another. Thus, ISAAC Phase Three has provided a large body of epidemiological information on asthma, rhinoconjunctivitis and eczema in childhood from contrasting environments which is expected to yield new clues about the aetiology of those conditions and reasons for their marked global variability. Copyright © 2012 SEICAP. Published by Elsevier Espana. All rights reserved.

  4. Rutting performance of cold bituminous emulsion mixtures

    Science.gov (United States)

    Arshad, Ahmad Kamil; Ali, Noor Azilatom; Shaffie, Ekarizan; Hashim, Wardati; Rahman, Zanariah Abd

    2017-10-01

    Cold Bituminous Emulsion Mixture (CBEM) is an environmentally friendly alternative to hot mix asphalt (HMA) for road surfacing, due to its low energy requirements. However, CBEM has generally been perceived to be less superior in performance, compared to HMA. This paper details a laboratory study on the rutting performance of CBEM. The main objective of this study is to determine the Marshall properties of CBEM and to evaluate the rutting performance. The effect of cement in CBEM was also evaluated in this study. The specimens were prepared using Marshall Mix Design Method and rutting performance was evaluated using the Asphalt Pavement Analyzer (APA). Marshall Properties were analysed to confirm compliance with the PWD Malaysia's specification requirements. The rutting performance for specimens with cement was also found to perform better than specimens without cement. It can be concluded that Cold Bituminous Emulsion Mixtures (CBEM) with cement is a viable alternative to Hot Mix Asphalt (HMA) as their Marshall Properties and performance obtained from this study meets the requirements of the specifications. It is recommended that further study be conducted on CBEM for other performance criteria such as moisture susceptibility and fatigue.

  5. Selection of an Alternate Biocide for the ISS Internal Thermal Control System Coolant, Phase 2

    Science.gov (United States)

    Wilson, Mark E.; Cole, Harold; Weir, Natalee; Oehler, Bill; Steele, John; Varsik, Jerry; Lukens, Clark

    2004-01-01

    The ISS (International Space Station) ITCS (Internal Thermal Control System) includes two internal coolant loops that utilize an aqueous based coolant for heat transfer. A silver salt biocide had previously been utilized as an additive in the coolant formulation to control the growth and proliferation of microorganisms within the coolant loops. Ground-based and in-flight testing demonstrated that the silver salt was rapidly depleted, and did not act as an effective long-term biocide. Efforts to select an optimal alternate biocide for the ITCS coolant application have been underway and are now in the final stages. An extensive evaluation of biocides was conducted to down-select to several candidates for test trials and was reported on previously. Criteria for that down-select included: the need for safe, non-intrusive implementation and operation in a functioning system; the ability to control existing planktonic and biofilm residing microorganisms; a negligible impact on system-wetted materials of construction; and a negligible reactivity with existing coolant additives. Candidate testing to provide data for the selection of an optimal alternate biocide is now in the final stages. That testing has included rapid biocide effectiveness screening using Biolog MT2 plates to determine minimum inhibitory concentration (amount that will inhibit visible growth of microorganisms), time kill studies to determine the exposure time required to completely eliminate organism growth, materials compatibility exposure evaluations, coolant compatibility studies, and bench-top simulated coolant testing. This paper reports the current status of the effort to select an alternate biocide for the ISS ITCS coolant. The results of various test results to select the optimal candidate are presented.

  6. Shedding light on the different behavior of ionic and nonionic surfactants in emulsion polymerization: from atomistic simulations to experimental observations.

    Science.gov (United States)

    Magi Meconi, Giulia; Ballard, Nicholas; Asua, José M; Zangi, Ronen

    2017-12-06

    Although surfactants are known to play a vital role in polymerization reactions carried out in dispersed media, many aspects of their use are poorly understood, perhaps none more so than the vastly different action of ionic and nonionic surfactants in emulsion polymerization. In this work, we combine experimental measurements of emulsion polymerization of styrene with atomistic molecular dynamics simulations to better understand the behavior of surfactants at monomer/polymer-water interfaces. In a batch emulsion polymerization of styrene, the nonionic surfactant Disponil AFX 1080 leads to two nucleation periods, in contrast to the behavior observed for the ionic surfactant SDS. This can be explained by the absorption of the nonionic surfactant into the organic phase at the early stages of the polymerization reaction which is then released as the reaction progresses. Indeed, we find that the partition coefficient of the surfactant between the organic phase and water increases with the amount of monomer in the former, and preferential partitioning is detected to organic phases containing at least 55% styrene. Results from molecular dynamics simulations confirm that spontaneous dissolution of the non-ionic surfactant into a styrene-rich organic phase occurs above a critical concentration of the surfactant adsorbed at the interface. Above this critical concentration, a linear correlation between the amount of surfactant adsorbed at the interface and that absorbed inside the organic phase is observed. To facilitate this absorption into a completely hydrophobic medium, water molecules accompany the intruding surfactants. Similar simulations but with the ionic surfactant instead did not result in any absorption of the surfactant into a neat styrene phase, likely because of its strongly hydrophilic head group. The unusual partitioning behavior of nonionic surfactants explains a number of observable features of emulsion polymerization reactions which use nonionic

  7. Nozzleless Fabrication of Oil-Core Biopolymeric Microcapsules by the Interfacial Gelation of Pickering Emulsion Templates.

    Science.gov (United States)

    Leong, Jun-Yee; Tey, Beng-Ti; Tan, Chin-Ping; Chan, Eng-Seng

    2015-08-05

    Ionotropic gelation has been an attractive method for the fabrication of biopolymeric oil-core microcapsules due to its safe and mild processing conditions. However, the mandatory use of a nozzle system to form the microcapsules restricts the process scalability and the production of small microcapsules (microcapsules through ionotropic gelation at the interface of an O/W Pickering emulsion. This approach involves the self-assembly of calcium carbonate (CaCO3) nanoparticles at the interface of O/W emulsion droplets followed by the addition of a polyanionic biopolymer into the aqueous phase. Subsequently, CaCO3 nanoparticles are dissolved by pH reduction, thus liberating Ca(2+) ions to cross-link the surrounding polyanionic biopolymer to form a shell that encapsulates the oil droplet. We demonstrate the versatility of this method by fabricating microcapsules from different types of polyanionic biopolymers (i.e., alginate, pectin, and gellan gum) and water-immiscible liquid cores (i.e., palm olein, cyclohexane, dichloromethane, and toluene). In addition, small microcapsules with a mean size smaller than 100 μm can be produced by selecting the appropriate conventional emulsification methods available to prepare the Pickering emulsion. The simplicity and versatility of this method allows biopolymeric microcapsules to be fabricated with ease by ionotropic gelation for numerous applications.

  8. Platinum nanoparticles from size adjusted functional colloidal particles generated by a seeded emulsion polymerization process

    Directory of Open Access Journals (Sweden)

    Nicolas Vogel

    2011-08-01

    Full Text Available The benefits of miniemulsion and emulsion polymerization are combined in a seeded emulsion polymerization process with functional seed particles synthesized by miniemulsion polymerization. A systematic study on the influence of different reaction parameters on the reaction pathway is conducted, including variations of the amount of monomer fed, the ratio of initiator to monomer and the choice of surfactant and composition of the continuous phase. Critical parameters affecting the control of the reaction are determined. If carefully controlled, the seeded emulsion polymerization with functional seed particles yields monodisperse particles with adjustable size and functionalities. Size-adjusted platinum-acetylacetonate containing latex particles with identical seed particles and varied shell thicknesses are used to produce arrays of highly ordered platinum nanoparticles with different interparticle distances but identical particle sizes. For that, a self-assembled monolayer of functional colloids is prepared on a solid substrate and subsequently treated by oxygen plasma processing in order to remove the organic constituents. This step, however, leads to a saturated state of a residual mix of materials. In order to determine parameters influencing this saturation state, the type of surfactant, the amount of precursor loading and the size of the colloids are varied. By short annealing at high temperatures platinum nanoparticles are generated from the saturated state particles. Typically, the present fabrication method delivers a maximum interparticle distance of about 260 nm for well-defined crystalline platinum nanoparticles limited by deformation processes due to softening of the organic material during the plasma applications.

  9. Thermal hazard assessment of oxidizer solutions and emulsion explosives utilizing accelerating rate and Dewar calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.E.G.; Lightfoot, P.D.; Fouchard, R.C. [Natural Resources Canada, CANMET, Canadian Explosives Research Laboratory, Ottawa, ON (Canada)

    2002-07-01

    Accelerating rate calorimetry (ARC) and adiabatic Dewar calorimetric experiments were carried out on oxidizers used in the manufacture of emulsion explosives, their aqueous solutions, a bulk explosive matrix and a detonator-sensitive packaged explosive. The experiments were carried out in both closed and vented experimental configurations. The effects of water levels on the oxidizer solutions were investigated and the results obtained by using the two different techniques were compared. The Dewar experiments were found to yield a better direct estimation of bulk onset temperatures due to their greater sensitivity and lower 'phi factor'. Onset temperatures of oxidizer solutions measured using the Dewar calorimeter were found to be about 15 degrees C lower than those measured by ARC. Onset temperatures for the same oxidizer solution are lower for open systems than for closed systems. Results for emulsion explosives appeared complex, but indications are that oxidation of the oil phase in air is the first exothermic step in the runaway reaction. Whether this oxidation reaction can generate enough heat to drive the reaction to runaway, is not clear. Further elucidation of the complex exothermic reactions of emulsion explosives and their constituents, using both ARC and Dewar calorimetric techniques is recommended. 8 refs., 1 tab., 9 figs.

  10. EVALUATION OF STABILITY OF EMULSION OIL / WATER FRONT OF THE USE OF DIFFERENT SURFACTANTS

    Directory of Open Access Journals (Sweden)

    Fernanda Cristina Wiedusch Sindelar

    2013-05-01

    Full Text Available The reuse of waste generated by various industrial sectors is a practice that has been increasingly used due to impairment of industries with their social responsibility (environmental protection or the requirements of the protection of the environment, since many residues do not have proper disposal. In the processing industry in the reuse of stones is no different. This study aims to evaluate the reuse of the oil used as a lubricant in the stone processing industry, along with water, surfactants and corrosion. To prepare the emulsions samples were used of diesel oil as a lubricant used in the cutting industry this type of industry, plus the following surfactants: Tween 20, Tween 80, sodium lauryl ether sulphate and Cetiol HE. After completing the pH, viscosity, density and phase separation in these emulsions, the conclusion was reached that the surfactant Sodium Lauryl Ether Sulfate provided the best formulation. Using this result, new emulsions prepared with the surfactant Sodium Lauryl Ether Sulfate and an anticorrosive, in this case, sodium molybdate. In such solutions containing sodium molybdate were analyzed power anticorrosive this substance, using the SAE 1020 steel plates. After these analyzes, it was found that the addition of an anticorrosive may reduce or inhibit oxidation, but in other cases, as in this study, can promote oxidation even greater.

  11. Pickering Interfacial Catalysts for solvent-free biomass transformation: physicochemical behavior of non-aqueous emulsions.

    Science.gov (United States)

    Fan, Zhaoyu; Tay, Astrid; Pera-Titus, Marc; Zhou, Wen-Juan; Benhabbari, Samy; Feng, Xiaoshuang; Malcouronne, Guillaume; Bonneviot, Laurent; De Campo, Floryan; Wang, Limin; Clacens, Jean-Marc

    2014-08-01

    A key challenge in biomass conversion is how to achieve valuable molecules with optimal reactivity in the presence of immiscible reactants. This issue is usually tackled using either organic solvents or surfactants to promote emulsification, making industrial processes expensive and not environmentally friendly. As an alternative, Pickering emulsions using solid particles with tailored designed surface properties can promote phase contact within intrinsically biphasic systems. Here we show that amphiphilic silica nanoparticles bearing a proper combination of alkyl and strong acidic surface groups can generate stable Pickering emulsions of the glycerol/dodecanol system in the temperature range of 35-130°C. We also show that such particles can perform as Pickering Interfacial Catalysts for the acid-catalyzed etherification of glycerol with dodecanol at 150°C. Our findings shed light on some key parameters governing emulsion stability and catalytic activity of Pickering interfacial catalytic systems. This understanding is critical to pave the way toward technological solutions for biomass upgrading able to promote eco-efficient reactions between immiscible organic reagents with neither use of solvents nor surfactants. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Contrast enhancement by simultaneous ultrasound/laser pulse probing of gold nanosphere encapsulated emulsion beads

    Science.gov (United States)

    Wei, Chen-wei; Larson-Smith, Kjersta; Pelivanov, Ivan M.; Perez, Camilo; Xia, Jinjun; Pozzo, Danilo; Matula, Thomas J.; O'Donnell, Matthew

    2013-03-01

    A new technique using pulsed laser heating of a nanocomposite contrast agent resulting in local bubble formation and concomitant harmonic generation in a scattered probe ultrasound (US) beam is proposed to increase specific contrast in both US imaging and laser-induced photoacoustic (PA) imaging. The composite combines an emulsion bead core with amphiphilic gold nanospheres (GNSs) assembled at the interface. Clustered GNSs result in a broadened absorption spectrum in the near infrared range (700-1000 nm) compared to the typical 520 nm peak of distributed GNSs, enabling their use at depth in tissue. Illuminating the composite with a pulsed laser with appropriately chosen parameters heats the composite through optical absorption by the GNSs and results in a phase transition of the emulsion bead to form a transient bubble. By delivering a probe US pulse simultaneously, or immediately after the laser pulse is delivered, harmonic signals are produced in the scattered US beam. The results show that a residual signal created by subtracting a US signal from the simultaneous US/laser probing signal of the emulsion bead sample is 1.7 dB higher than the laser alone generated PA signal and 20 dB higher than the PA signal of a control homogeneous GNSs dispersion with the same optical absorption, indicating the nonlinear contrast enhancement from bubble dynamics. The proposed technique of local activation of this designed contrast agent can be used to dramatically enhance both the specificity and sensitivity of integrated US/PA molecular imaging.

  13. Determination of haplotypes at structurally complex regions using emulsion haplotype fusion PCR

    Directory of Open Access Journals (Sweden)

    Tyson Jess

    2012-12-01

    Full Text Available Abstract Background Genotyping and massively-parallel sequencing projects result in a vast amount of diploid data that is only rarely resolved into its constituent haplotypes. It is nevertheless this phased information that is transmitted from one generation to the next and is most directly associated with biological function and the genetic causes of biological effects. Despite progress made in genome-wide sequencing and phasing algorithms and methods, problems assembling (and reconstructing linear haplotypes in regions of repetitive DNA and structural variation remain. These dynamic and structurally complex regions are often poorly understood from a sequence point of view. Regions such as these that are highly similar in their sequence tend to be collapsed onto the genome assembly. This is turn means downstream determination of the true sequence haplotype in these regions poses a particular challenge. For structurally complex regions, a more focussed approach to assembling haplotypes may be required. Results In order to investigate reconstruction of spatial information at structurally complex regions, we have used an emulsion haplotype fusion PCR approach to reproducibly link sequences of up to 1kb in length to allow phasing of multiple variants from neighbouring loci, using allele-specific PCR and sequencing to detect the phase. By using emulsion systems linking flanking regions to amplicons within the CNV, this led to the reconstruction of a 59kb haplotype across the DEFA1A3 CNV in HapMap individuals. Conclusion This study has demonstrated a novel use for emulsion haplotype fusion PCR in addressing the issue of reconstructing structural haplotypes at multiallelic copy variable regions, using the DEFA1A3 locus as an example.

  14. Determination of haplotypes at structurally complex regions using emulsion haplotype fusion PCR.

    Science.gov (United States)

    Tyson, Jess; Armour, John A L

    2012-12-11

    Genotyping and massively-parallel sequencing projects result in a vast amount of diploid data that is only rarely resolved into its constituent haplotypes. It is nevertheless this phased information that is transmitted from one generation to the next and is most directly associated with biological function and the genetic causes of biological effects. Despite progress made in genome-wide sequencing and phasing algorithms and methods, problems assembling (and reconstructing linear haplotypes in) regions of repetitive DNA and structural variation remain. These dynamic and structurally complex regions are often poorly understood from a sequence point of view. Regions such as these that are highly similar in their sequence tend to be collapsed onto the genome assembly. This is turn means downstream determination of the true sequence haplotype in these regions poses a particular challenge. For structurally complex regions, a more focussed approach to assembling haplotypes may be required. In order to investigate reconstruction of spatial information at structurally complex regions, we have used an emulsion haplotype fusion PCR approach to reproducibly link sequences of up to 1kb in length to allow phasing of multiple variants from neighbouring loci, using allele-specific PCR and sequencing to detect the phase. By using emulsion systems linking flanking regions to amplicons within the CNV, this led to the reconstruction of a 59kb haplotype across the DEFA1A3 CNV in HapMap individuals. This study has demonstrated a novel use for emulsion haplotype fusion PCR in addressing the issue of reconstructing structural haplotypes at multiallelic copy variable regions, using the DEFA1A3 locus as an example.

  15. Internal noise in channelized Hotelling observer (CHO) study of detectability index-differential phase contrast CT vs. conventional CT

    Science.gov (United States)

    Tang, Xiangyang; Yang, Yi

    2014-03-01

    The channelized Hotelling observer (CHO) model, wherein internal noise plays an important role to account for the psychophysiological uncertainty in human's visual perception, has found extensive applications in the assessment of image quality in nuclear medicine, mammography and conventional CT. Recently, we extended its application to investigating the detectability index of differential phase contrast (DPC) CT-an emerging CT technology with the potential of increasing the capability in soft tissue differentiation. We found that the quantitative determination of internal noise in the CHO study of DPC-CT's detectability index should differ from that in the conventional CT. It is believed that the root cause of such a difference lies in the distinct noise spectra between the DPC-CT and conventional CT. In this paper, we present the preliminary results and investigate the adequate strategies to quantitatively determine the internal noise of CHO model for its application in the assessment of image quality in DPC-CT and its comparison with that of the conventional CT.

  16. Further progress for a fast scanning of nuclear emulsions with Large Angle Scanning System

    Science.gov (United States)

    Alexandrov, A.; Tioukov, V.; Vladymyrov, M.

    2014-02-01

    The LASSO (Large Angle Scanning System for OPERA) is a scanning system designed in the framework of the OPERA experiment as a result of several R&Ds aimed to improve the performance of the European Scanning System (ESS) by increasing the scanning speed, the angular acceptance and the efficiency in microtrack reconstruction. The novel Continuous Motion (CM) scanning approach allows to double the ESS nominal speed without any changes in the hardware set-up. The LASSO modular design makes the system easily adaptable to new hardware. The novel microtrack reconstruction algorithm has been developed to be efficient in both standard Stop&Go (SG) and CM modes, performing a number of corrections during the processing like corrections for vibrations, optical distortions, field of view curvature. As an intermediate step it reconstructs silver grains positions inside emulsion layer to make a transition from 2D images to real 3D traces of a charged particle. This allows the algorithm to have no internal limits on the slope of microtracks being equally efficient on all angles. The LASSO has been used for about one year for mass production scanning of emulsion films of OPERA, Muon Radiography and also of films employed to study nuclear fragmentation of ion beams used in medical physics. More than 50000 cm2 of the emulsion surface have been analyzed during this period.

  17. International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Sudan. February-March 1981

    International Nuclear Information System (INIS)

    Kneupper, G.; Scivetti, N.

    1981-01-01

    The IUREP Orientation Phase Mission to the Democratic Republic of the Sudan believes that the Speculative Resources of the country might fall between 20,000 and 40,000 tonnes uranium and more. This indicates that the Speculative Resources of the Sudan could be significantly higher than previously estimated (7,500 tonnes uranium) by the NEA/IAEA Steering Group on the Uranium Resources - IUREP Phase I. The Government is willing to consider valid exploration programmes presented by prospective partners as long as they serve the interests of both parties. Within the general six-year (1977/78-1982/83) plan for development of the country's mineral resources, the Ministry of Energy and Mining has set up certain priorities which it would like to see expeditiously implemented: uranium exploration and production stands high on the list of priorities. On the basis of very limited information on regional geology and on previous exploration which was available to the Mission, it is estimated that the greatest potential for the Speculative Resources of possible economic significance will prove to occur in the following geological environments of the Sudan (Red Sea Hills area is not included): precambrian basement complex, palaeozoic-mesozoic-tertiary sedimentary basins and the tertiary to recent calcretes. The IUREP Orientation Phase Mission believes that some 20 Million US$ (very rough estimate) will be needed to (1) check the validity of the basic geological concepts formulated on the uranium potential of the selected areas, (2) accumulate diagnostic geological, geophysical, geochemical data indicative of a true uranium potential there, (3) study the basement complex rocks and the sedimentary formations at least on a broad structural-stratigraphic reconnaissance basis (a tremendous amount of valuable water drilling data has accumulated over the last years for some of the selected sedimentary basins) and (4) determine the most appropriate investigation techniques to be utilized

  18. "Vitamin E" fortified parenteral lipid emulsions: Plackett-Burman screening of primary process and composition parameters.

    Science.gov (United States)

    Alayoubi, Alaadin; Nazzal, Mahmoud; Sylvester, Paul W; Nazzal, Sami

    2013-02-01

    The objective of this study was to screen the effect of eight formulations and process parameters on the physical attributes and stability of "Vitamin E"-rich parenteral lipid emulsions. Screening was performed using a 12-run, 8-factor, 2-level Plackett-Burman design. This design was employed to construct polynomial equations that identified the magnitude and direction of the linear effect of homogenization pressure, number of homogenization cycles, primary and secondary emulsifiers, pre-homogenization temperature, oil loading, and ratio of vitamin E to medium-chain triglycerides (MCT) in the oil phase on particle size, polydispersity index, short-term stability, and outlet temperature of manufactured emulsions. The viscosity of vitamin E was reduced from 3700 (100%) to 64 mPa.s (30%) by MCT addition. As viscosity is critical for efficient emulsification, vitamin/MCT ratio was the most significant contributor for the stability of emulsions. Particle size increased from 236 to 388 nm, and percentage vitamin remaining emulsified after 48 h dropped from 100 to 73% with increase in vitamin/MCT ratio from 30/70 to 70/30. Significant decrease in particle size and PI, and an increase in outlet temperature were also observed with increase in homogenization pressure and number of homogenization cycles. Emulsifiers and oil loading, however, had insignificant effect on the responses. Overall, stable submicron emulsions at vitamin/MCT ratio of 30/70 could be prepared at 25,000 psi and 25 cycles in ambient conditions. The identification of these parameters by a well-constructed design demonstrated the utility of screening studies in the "Quality by Design" approach to pharmaceutical product development.

  19. Attachment of Alcanivorax borkumensis to Hexadecane-in-Artificial Sea Water Emulsion Droplets.

    Science.gov (United States)

    Abbasi, Akram; Bothun, Geoffrey D; Bose, Arijit

    2018-04-16

    Alcanivorax borkumensis (AB) is a marine bacterium that dominates bacterial communities around many oil spills because it enzymatically degrades the oil while using it as a nutrient source. Several dispersants have been used to produce oil-in-water emulsions following a spill. Compared to surface slicks, the additional oil-water surface area produced by emulsification provides greater access to the oil, and accelerates its degradation. We deliberately cultured AB cells using hexadecane as the only nutrient source. We then examined the first critical step of the biodegradation process, the attachment of these AB cells to hexadecane-water interfaces, using fluorescence microscopy and cryogenic scanning electron microscopy. The hexadecane-in-artificial sea water (ASW) emulsions were produced by gentle shaking, and were stabilized either by AB alone, by Corexit 9500, by Tween 20, or by carbon black particles. When no dispersants were used, AB stabilizes the emulsion, and bacterial cells attach to the hexadecane droplets within the first 3 days. When Corexit 9500 was used as the dispersant, AB did not attach to the hexadecane droplets over 3 days, and many AB cells in the aqueous phase appeared dead. Only limited attachment was observed after 7 days. No AB attachment was observed over 3 days when Tween 20 was used as the dispersant. However, the bacteria used Tween 20 in the ASW as a nutrient. Large amounts of AB attached to carbon black stabilized hexadecane droplets within 3 days. An analysis that accounts for van der Waals and electrostatic interactions is unable to predict all of these observations, indicating that the attachment of AB to the hexadecane is a complex phenomenon that goes beyond simple physiochemical effects. While these experiments do not mimic conditions in the open ocean where the large amount of water dilutes any emulsion stabilizer, they provide important insights on bacteria adhesion to oil, a critical step in the oil degradation process

  20. Discourse of the form and concentration of surfactants to ensure the sustainability foam-emulsive products

    Directory of Open Access Journals (Sweden)

    Oleg

    2015-05-01

    Full Text Available Introduction. Development of dry mixes for making spumy and emulsion products are topical, because nowadays there is a tendency to minimize the time spent on the process of cooking, which is achieved by the use of semi finished products high degree of readiness. Materials and methods. Foaming ability was determined by the method of multiplicity of the foam, the stability of unstable foam-by the half-life method of foam, highly resistant foam - as a ratio of the height of the column of foam after exposure for 24 hours. Results. Was determined the influence of sunflower oil on the foaming ability and half-life foam of systems «sodium caseinate-oil». It was found that getting systems with high index of foaming capacity and foam stability in the presence of oil in the system is impossible without the use of low molecular weight surfactants. Substantiated recommendations regarding the feasibility of using two surfactants in systems «sodium caseinate-surfactants-oil», which provide the necessary kinship surfaces air, fat and water phases. it has been found that the use of 2,5...3,5% mono-and diglycerides of fatty acid sand Lecithin’s 0.15...0.25% in the content of sodium caseinate about 0.5% allows to receive the stable foam-emulsive systems containing sunflower oil 7...8% and foaming ability about 640±1%. Conclusions. It is established that for ensuring high indicators foaming capacity and stability of foam-emulsive systems required the use of low-molecular surfactants. The research results, is recommended to use when developing technology of foam-emulsive products.