A new reactor with integrated conventional slurry stirred reactor and ceramic external membrane emulsification system, was introduced in this paper. Toluene and toluene containing surfactant was separately used as dis...A new reactor with integrated conventional slurry stirred reactor and ceramic external membrane emulsification system, was introduced in this paper. Toluene and toluene containing surfactant was separately used as dispersed phase for preparation of emulsions. Two kinds of emulsions were prepared and compared. The volume average sizes of prepared emulsions were 3.53μm and 3.6μm respectively. The results showed that the droplet sizes of two kinds of emulsions were similar, but the monodispersed emulsion was only obtained with addition of surfactant into the dispersed phase.展开更多
Microcapsules (or microspheres) with small size and narrow size distribution have potential applications as carriers of proteins and polypeptides. However the conventional preparation methods severely limit their real...Microcapsules (or microspheres) with small size and narrow size distribution have potential applications as carriers of proteins and polypeptides. However the conventional preparation methods severely limit their real applications. Membrane emulsification technology may become a new preparation method of microcapsules with monodisperse droplets, mild conditions, good stability, low energy consumption and easy to realize mass production. In this paper, studies on membrane emulsification systems and the possible existing problems are summarized, and primary attempts on preparing alginate/chitosan microcapsules are conducted.展开更多
Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant...Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant sodium alkyl glucosyl hydroxypropyl sulfonate(APGSHS) and zwitterionic surfactant octadecyl betaine(BS-18) is proposed. The performance of APGSHS/BS-18 mixed surfactant system was evaluated in terms of interfacial tension, emulsification capability, emulsion size and distribution, wettability alteration, temperature-resistance and salt-resistance. The emulsification speed was used to evaluate the emulsification ability of surfactant systems, and the results show that mixed surfactant systems can completely emulsify the crude oil into emulsions droplets even under low energy conditions. Meanwhile,the system exhibits good temperature and salt resistance. Finally, the best oil recovery of 25.45% is achieved for low permeability core by the mixed surfactant system with a total concentration of 0.3 wt%while the molar ratio of APGSHS:BS-18 is 4:6. The current study indicates that the anionic/zwitterionic mixed surfactant system can improve the oil flooding efficiency and is potential candidate for application in low permeability reservoirs.展开更多
The separation of phases after the stability composition at a plait point is exceeded has significant effect on the reactions during spontaneous emulsification, but experimental efforts to obtain accurate information ...The separation of phases after the stability composition at a plait point is exceeded has significant effect on the reactions during spontaneous emulsification, but experimental efforts to obtain accurate information are extremely difficult, because even the smallest scattering of the numbers has a large effect on the result. In the present contribution a model system was applied that closely mirrored experimental values and the mass ratio of the two phases could be calculated with high accuracy. Extrapolation of the ratio between phase masses towards the critical composition showed the two phase masses each close to 0.5, while a composition with a miniscule difference from this composition extrapolated to 1.0. The results showed spontaneous emulsification between solutions at the plait point and water to consist of two processes;an initial extremely fast reaction and a slower process between the aqueous phase formed in the primary emulsification and water.展开更多
Solvent extraction is the main method used to separate and purify rare earth elements.In the process of rare earths extraction,emulsification often generated due to the instability of the aqueous and organic phases or...Solvent extraction is the main method used to separate and purify rare earth elements.In the process of rare earths extraction,emulsification often generated due to the instability of the aqueous and organic phases or improper operating conditions.Once emulsification occurs,it would not only lead to low rare earths recovery efficiency,small product quantities,high production costs and the losing of extractant and rare earth resources,but also result in serious environmental pollution.Therefore,it is very important to study the micro-mechanisms of emulsification and establish new methods to prevent emulsification at the source.In this paper,possible factors resulting in emulsification,such as the compositions and properties of the organic and aqueous phases,the operating conditions of the rare earths extraction are reviewed.The micro-mechanisms of emulsification are summarized basing on the microscopic structures in the bulk phase,aggregations of the extractants at the organic-aqueous interface,spectral characterizations and computational simulations.On this basis,new formation mechanisms are proposed for emulsification.Preliminary explorations are employed to verify the correctness of these new viewpoints.Finally,future directions for studies of the emulsification micro-mechanism are proposed.This study provides a theoretical basis for further understanding the micro-mechanisms of interfacial instability resulting in emulsification in the process of rare earths extraction.展开更多
Emulsions are widely used across various industries but often require surfactants for stabilization,leading to complex product formulations and environmental concerns.Continuous preparation of stable emulsions without...Emulsions are widely used across various industries but often require surfactants for stabilization,leading to complex product formulations and environmental concerns.Continuous preparation of stable emulsions without surfactants is still a significant challenge.Herein,a secondary membrane emulsification system was developed to produce stable oil-in-water emulsions under surfactant-free conditions,where the first membrane module employed the cross-flow membrane emulsification to generate the primary emulsion,while the second membrane module employed the premix membrane emulsification to further reduce the droplet size,thereby improving the emulsion stability.The morphology and droplet size of the secondary emulsion significantly depend on the membrane pore size,membrane surface wettability,primary emulsion flow,and primary emulsion quality.The secondary membrane emulsification system demonstrates excellent operational stability over 12 h,with no obvious changes in the emulsion characteristics.The prepared secondary emulsion remains relatively stable up to 10 min without surfactants,significantly superior to the primary emulsion.Furthermore,the developed system successfully produces the Janus emulsion with homogeneous internal phase morphology.This research provides an effective approach for the continuous preparation of stable emulsions without surfactants.展开更多
AIM:To elucidate the manifestations and associated complications observed in patients with intraocular silicone oil(SO)emulsification through multiple imaging modalities.METHODS:This single-center,observational,retros...AIM:To elucidate the manifestations and associated complications observed in patients with intraocular silicone oil(SO)emulsification through multiple imaging modalities.METHODS:This single-center,observational,retrospective study included 116 patients who underwent pars plana vitrectomy(PPV)with SO injection for retinal detachment(RD),followed by subsequent SO removal at the Second Hospital of Hebei Medical University from January 2013 to January 2023.Comprehensive records of ophthalmic examinations utilizing multiple imaging techniques were maintained.RESULTS:The study comprised 56 females and 60 males,with a mean age of 52.75±13.6y.The mean follow-up duration for SO tamponade was 9.04±11.33mo(range:1-84mo).Among the participants,59 patients were diagnosed with SO emulsification,while 57 patients were in the SO unemulsified group.Patients with SO emulsification had a significantly prolonged SO tamponade duration(P<0.01).Multiple imaging techniques revealed notable signs of SO emulsification and its complications,such as 4 cases(3.4%)with posterior corneal SO-like keratic precipitates(KP)observed by anterior segment photography,23 cases(19.8%)exhibiting spherical high-reflection signals in the inter-retina,retinal pigment epithelium,or choroid detected by Spectralis spectral domain optical coherence tomography(SD-OCT),4 cases(3.4%)showing slow movement of emulsified SO droplets within retinal vessels during fluorescein angiography(FFA),plain and enhanced head magnetic resonance imaging(MRI)images of these four patients did not detect emulsified SO in the lateral ventricles,suprasellar cistern,subarachnoid space,third ventricle,fourth ventricle,or other intracranial locations.CONCLUSION:Intraocular emulsified SO can lead to damage in both anterior and posterior segment tissues,encompassing corneal degeneration,cataracts,glaucoma,retinal and choroid inflammation.Objective multiple imaging techniques such as anterior segment photography,SD-OCT,FFA,and MRI offer comprehensive evaluation and diagnosis of SO emulsification and its associated complications.展开更多
In the present study,an extended-release(ER)suspension of guanfacine hydrochloride(GFN)was successfully formulated using a self-synthesized cation-exchange resin characterized by a narrow particle size distribution.Th...In the present study,an extended-release(ER)suspension of guanfacine hydrochloride(GFN)was successfully formulated using a self-synthesized cation-exchange resin characterized by a narrow particle size distribution.The drug-resin complex was prepared through a static adsorption method,employing the resin as a pharmaceutical carrier.Subsequently,guanfacine hydrochloride-coated microcapsules(GFN-CM)were fabricated via an emulsion solvent evaporation technique to achieve sustained-release functionality.Characterization revealed that the in-house resin exhibited a smoother surface and a narrower size distribution(Span value:0.74)compared to the commercial counterpart,Amberlite®IRP69.In vitro release studies demonstrated that the GFN-CM followed a zero-order kinetic model over 10 h,with a cumulative drug release of 81.88%observed at 12 h.Furthermore,pharmacokinetic evaluation in New Zealand rabbits showed that the mean residence time(MRT0–24)of the GFN suspension extended from 7.619 to 8.336 h,displaying a more stable plasma concentration-time profile and an average relative bioavailability(Fr)of 111.36% compared to marketed ER GFN tablets.These findings highlighted the successful development of a novel cation exchange resin-based delivery system,offering a promising strategy for enhancing the performance of ER pharmaceutical formulations.展开更多
Emulsification troubled normal extraction process of rare earths due to the existence of non-rare earth impurities, especially Si, Al and Fe. Against this background, the effect of emulsification caused by Si, Al and ...Emulsification troubled normal extraction process of rare earths due to the existence of non-rare earth impurities, especially Si, Al and Fe. Against this background, the effect of emulsification caused by Si, Al and Fe on the La extraction with saponification P507 (2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester) in chloride medium was systematically investigated. A series of experiments were carried out to study the relationship of the extraction capacity of La and the concentration of impurities. ZPM-203 polarizing microscope was applied to investigate the morphology of emulsification, and the cation exchange extraction mechanism of Fe and Al as well as La was clarified by IR spectra. The results showed that a low concentration of Si in organic phase would aggravate the emulsification with Al, and the formation of ME (micro emulsion) and club-shaped polymer would result in emulsification in the extraction of mixtures of Si and Al, single Fe, respectively. Furthermore, the accumulation of impurity such as Si, Al and Fe in the organic phase would severely reduce the extraction capacity of La simultaneously.展开更多
In this review, our recent work in phase inversion emulsification (PIE) for polymer (especially epoxy resin) waterborne dispersions is summarized. Based on experimental results about PIE process, the physical mode...In this review, our recent work in phase inversion emulsification (PIE) for polymer (especially epoxy resin) waterborne dispersions is summarized. Based on experimental results about PIE process, the physical model is proposed which can guide the synthesis of the waterborne dispersions such as polymer/nanoparticle composite dispersion. In the presence of a latent curing catalyst, PIE can give a crosslinkable epoxy resin waterborne dispersion. The dispersions can form cured transparent coatings with some unique properties such as UV shielding. They are promising in functional coatings, waterborne resin matrices for composites, and sizing for high performance fibers.展开更多
The aim of this study is to report and analyze the factors related with earlier occurrence of silicone oil(SO) emulsification in patients underwent pars plana vitrectomy and SO injection in our hospital. We retrospect...The aim of this study is to report and analyze the factors related with earlier occurrence of silicone oil(SO) emulsification in patients underwent pars plana vitrectomy and SO injection in our hospital. We retrospectively reviewed consecutive case series undergone both SO injection and removal in our hospital, and 182 ones were eligible. Possible related independent factors included: macula status(on/off), concomitant phacoemulsification with the surgery of SO tamponading, concomitant status of proliferative vitreoretinopathy, combined surgery of retinotomy, time to have emulsification(<6 mo/≥6 mo after primary SO injection), route of SO injection(anterior/posterior), lens status(aphakic/pseudophakic/phakic), anesthesia(local/general), brands and type of SO, with/without episcleral cryotherapy, with/without hypertension, with/without diabetes, with/without intraoperative use of triamcinolone acetonide. The study revealed that brand and type of SO was the significant factor related with earlier emulsification of SO. Further study was warranted to find out the underlying causes.展开更多
Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)process.However,field trials have shown that low concentration surfactant fl...Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)process.However,field trials have shown that low concentration surfactant flooding can also improve oil recovery without ultra-low IFT.To clarify the mechanism behind,the currently-used surfactant,naphthenic arylsulfonate(NAS),was used to unravel its function during surfactant flooding from the horizon of micron-and nano-scale.The solubilization capacity of NAS micelle to petroleum fractions was evaluated through light absorbance strategy,smallangle neutron scattering,dynamic light scattering and transmission electron microscopy.It was found that micellar solubilization plays a significant role during the surfactant flooding.In-situ emulsification was visualized in microfluidics with three types of microchips,respectively.A series of displacement tests were carried out with NAS solution pumping into oil-saturated chip.The results show that in-situ emulsification improve oil recovery mainly through blocking and entrainment effects.Results from this work aid in understanding the interaction between surfactant solution and petroleum fractions at low surfactant concentration,which is helpful for design surfactant-based displacing system for EOR process.展开更多
P507 solvent extraction is the main method to separate and purify the rare earth products.The emulsification may be caused by the impurities in process of extracting rare earths,and these result in huge economic loss ...P507 solvent extraction is the main method to separate and purify the rare earth products.The emulsification may be caused by the impurities in process of extracting rare earths,and these result in huge economic loss and decrease the quality of rare earth products.In recent researches,the extractant was prone to emulsification,and aluminum content of rare earth products also increased,while aluminum concentration of feed was higher.Pointing to this problem,the structural change of saponification P507 extracting aluminum and lanthanum was investigated by infrared spectroscopy,and the results showed that Al ions exchanged with H of P-O-H to become P-O-Al.Because aluminum held the characteristic of hydrophilic after extracted in the form of hydroxyl polymer ions and this provided conditions for the formation of micro emulsion.The organic phase and aqueous phase were investigated by polarizing microscope after aluminum was extracted.The results showed that the organic phase was clear when the extraction capacity of Al was less than 5 g/L.If the extraction capacity of Al exceeded 5 g/L,it formed W/O of ME(micro emulsion),leading to form emulsion of the organic phase.When Al concentration of feed was less than 1 g/L,the aqueous phase would form O/W of ME.If aluminum was extracted by saponification P507 firstly,then the the organic phase loading aluminum extracted rare earth continually,the organic and aqueous phase formed emulsification easily.展开更多
AIM:To investigate the rates of emulsification in silicone oil(SO)tamponades of differing viscosities used during pars plana vitrectomy(PPV)in the treatment of complicated vitreoretinal diseases.METHODS:This study was...AIM:To investigate the rates of emulsification in silicone oil(SO)tamponades of differing viscosities used during pars plana vitrectomy(PPV)in the treatment of complicated vitreoretinal diseases.METHODS:This study was a prospective randomized clinical trial.Totally 290 cases with greater likelihoods of secondary detachment were included and randomly grouped into either Siluron 2000(n=143)or Siluron 5000(n=147)SO tamponades with 23-gauge PPV.Patient followups and data analyses were conducted 1,3,6,and 12 mo post-surgery.RESULTS:The time of the SO emulsification ranged from 1 to 17 mo,with a mean of 7.3±4.2 mo.The Siluron 5000 group showed a slower emulsification rate in comparison to the Siluron 2000 group.The Siluron 2000 group took a shorter time to show signs of emulsification,necessitating earlier SO removal.However,there were no significant differences in the occurrence of complications,including secondary retinal detachment,cataract,corneal abnormality,high intraocular pressure and hypotony.CONCLUSION:The Siluron 2000 SO tamponade shows a faster rate of emulsification than the Siluron 5000 SO,necessitating earlier removal.Both groups show similar results in terms of anatomical success and visual acuity outcome,and there is no significant difference between the SOs regarding the occurrence of complications.展开更多
The emulsification of crude oil is caused by the oil flowing into the water,resulting in the increase of oil film tension,viscosity,water content,and volume,which brings great harm to the marine ecological environment...The emulsification of crude oil is caused by the oil flowing into the water,resulting in the increase of oil film tension,viscosity,water content,and volume,which brings great harm to the marine ecological environment and difficulties for the cleanup of marine emergency equipment.The realization observation of emulsification crude oil will increase the response speed of marine emergency response.Therefore,we set up crude oil emulsification samples to study the physical property in laboratory and conducted radar measurements at different incidence angles in outdoor.The radar is C band in resolution of 0.7 m by 0.7 m.A fully polarimetric scatterometer(HH,VV,and VH/HV)is mounted at 1.66 m(minimum altitude)height at an incidence angle between 35°and 60°.An asphalt content of less than 3%crude oil and the filtered seawater were used to the outdoor emulsification scattering experiment.The measurement results are as follows.The water content can be used to describe the process of emulsification and it is easy to measure.Wind speed,asphalt content,seawater temperature,and photo-oxidation affect the emulsifying process of crude oil,and affects the normalized radar cross section(NRCS)of oil film but wind is not the dominant factor.It is the first time to find that the emulsification of crude oil results in an increase of NRCS.展开更多
As reported in this paper, a strain of oil-degrading bacterium Sp - 5 - 3 was determined to belong to Enterobacteriaceae, which would be useful for microbial enhanced oil recovery (MEOR). The aim of our study was to g...As reported in this paper, a strain of oil-degrading bacterium Sp - 5 - 3 was determined to belong to Enterobacteriaceae, which would be useful for microbial enhanced oil recovery (MEOR). The aim of our study was to generate a mutant using low energy N+ beam implantation. With 10 keV of energy and 5.2× 1014 N+/cm2 of dose - the optimum condition, a mutant, S-34, was obtained, which had nearly a 5-fold higher surface and a 13-fold higher of emulsifica-tion activity than the wild type. The surface activity was measured by two methods, namely, a surface tension measuring instrument and a recording of the repulsive circle of the oil film; the emulsification activity was scaled through measuring the separating time of the oil-fermentation mixture. The metabolic acid was determined as methane by means of gas chromatography.展开更多
Surface active ionic liquids (SAILs) are considered as prominent materials in enhanced oil recovery thanks to their high interfacial activity. This study reports the preparation and applications of a nanostructure Tri...Surface active ionic liquids (SAILs) are considered as prominent materials in enhanced oil recovery thanks to their high interfacial activity. This study reports the preparation and applications of a nanostructure Tripodal imidazolium SAIL as an environmentally-friendly substitute to the conventional surfactants. The product has a star-like molecular structure centered by a triazine spacer, namely [(C_(4)im)_(3)TA][Cl_(3)], prepared by a one-step synthesis method and characterized with FT-IR, NMR, XRD, and SEM analysis methods. The interfacial tension of the system was decreased to about 78% at critical micelle concentration of less than 0.08 mol·dm^(−3). Increasing temperature, from 298.2 to 323.2 K, improved this capability. The solid surface wettability was changed from oil-wet to water-wet and 80% and 77% stable emulsions of crude oil–aqueous solutions were created after one day and one week, respectively. Compared to the Gemini kind homologous SAILs, the superior effects of the Tripodal SAIL were revealed and attributed to the strong hydrophobic branches in the molecule. The Frumkin adsorption isotherm precisely reproduced the generated IFT data, and accordingly, the adsorption and thermodynamic parameters were determined.展开更多
A novel method to prepare macroporous TiO2 ceramic, based on membrane emulsification was reported.To solve the paradox between the instability of nonaqueous emulsion and long emulsification time required by themembran...A novel method to prepare macroporous TiO2 ceramic, based on membrane emulsification was reported.To solve the paradox between the instability of nonaqueous emulsion and long emulsification time required by themembrane emulsification, a two-stage ceramic membrane jet-flow emulsification .was. proposed. Discussion wasconducted on the evolution of droplet size with time, which followed the Ostwalcl npemng theory. And a monodispersed nonaqueous emulsion with an average droplet size of 1.6μm could beprepared. Using the emulsion, as atemplate, TiO2 ceramics with an average pore size ot 1.1 μm were obtaineed. Tne material could be prospectivelyused for preparation of catalysts, adsorbents, and membranes.展开更多
This research studied the initiator efficiency for producing polymeric particles of poly(styrene-co-methyl methacrylate)copolymers by a Shirasu porous glass membrane(SPG)emulsification technique followed by suspension...This research studied the initiator efficiency for producing polymeric particles of poly(styrene-co-methyl methacrylate)copolymers by a Shirasu porous glass membrane(SPG)emulsification technique followed by suspension copolymerization.BPO,ADVN,and AIBN were used as initiators and we found that BPO is the most suitable initiator.Copolymers for various feed ratios of styrene/methyl methacrylate were thus synthesized by benzoyl peroxide,and their copolymer particle size,molecular weight distribution and pat-ride size distribution were characterized.Then n-BMA or 2-EHMA was added as the third monomer to decrease the terpolymer glass transition temperature.This article describes the preparation technique,recipes and polymerization conditions for producing both copolymer and terpolymer particles,particle size changes,the corresponding particle morphologies and glass transition temperatures.展开更多
The mechanism of phase inversion emulsification process (PIE) was studied for waterborne dispersion of highly viscous epoxy resin using non-ionic polymeric surfactants. Drop deformation and breakup, rheological prop...The mechanism of phase inversion emulsification process (PIE) was studied for waterborne dispersion of highly viscous epoxy resin using non-ionic polymeric surfactants. Drop deformation and breakup, rheological properties, conductivity, and particle size measurements reveal the micro-structural transition amid emulsification. It is revealed that strong flow causes water drop to burst with the formation of droplets and huge interface. Phase inversion corresponds to an abrupt rheological transition from a type of viscous melt with weak elasticity to a highly elastic type of aqueous gel. This implies that the phase inversion equivalent to a curvature inversion. Based on this, a geometric model is postulated to correlate process variables to the particle size. The coverage and conformation of the surfactant plays key role for the particle size of the final emulsion. The interactions of thermodynamic and hydrodynamic effects are also discussed. It is concluded that the thermodynamics control the PIE while the hydrodynamics drives the creation of interface and involves every step of PIE.展开更多
基金the National Basic Research Program of China (No. 2003CB615700) the National Natural Science Foundation of China (No. 20125618).
文摘A new reactor with integrated conventional slurry stirred reactor and ceramic external membrane emulsification system, was introduced in this paper. Toluene and toluene containing surfactant was separately used as dispersed phase for preparation of emulsions. Two kinds of emulsions were prepared and compared. The volume average sizes of prepared emulsions were 3.53μm and 3.6μm respectively. The results showed that the droplet sizes of two kinds of emulsions were similar, but the monodispersed emulsion was only obtained with addition of surfactant into the dispersed phase.
基金Sponsored by the National Natural Science Foundation of China (No.29906011)
文摘Microcapsules (or microspheres) with small size and narrow size distribution have potential applications as carriers of proteins and polypeptides. However the conventional preparation methods severely limit their real applications. Membrane emulsification technology may become a new preparation method of microcapsules with monodisperse droplets, mild conditions, good stability, low energy consumption and easy to realize mass production. In this paper, studies on membrane emulsification systems and the possible existing problems are summarized, and primary attempts on preparing alginate/chitosan microcapsules are conducted.
基金financially supported by National Natural Science Foundation of China(No.22302229)Beijing Municipal Excellent Talent Training Funds Youth Advanced Individual Project(No.2018000020124G163)。
文摘Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant sodium alkyl glucosyl hydroxypropyl sulfonate(APGSHS) and zwitterionic surfactant octadecyl betaine(BS-18) is proposed. The performance of APGSHS/BS-18 mixed surfactant system was evaluated in terms of interfacial tension, emulsification capability, emulsion size and distribution, wettability alteration, temperature-resistance and salt-resistance. The emulsification speed was used to evaluate the emulsification ability of surfactant systems, and the results show that mixed surfactant systems can completely emulsify the crude oil into emulsions droplets even under low energy conditions. Meanwhile,the system exhibits good temperature and salt resistance. Finally, the best oil recovery of 25.45% is achieved for low permeability core by the mixed surfactant system with a total concentration of 0.3 wt%while the molar ratio of APGSHS:BS-18 is 4:6. The current study indicates that the anionic/zwitterionic mixed surfactant system can improve the oil flooding efficiency and is potential candidate for application in low permeability reservoirs.
文摘The separation of phases after the stability composition at a plait point is exceeded has significant effect on the reactions during spontaneous emulsification, but experimental efforts to obtain accurate information are extremely difficult, because even the smallest scattering of the numbers has a large effect on the result. In the present contribution a model system was applied that closely mirrored experimental values and the mass ratio of the two phases could be calculated with high accuracy. Extrapolation of the ratio between phase masses towards the critical composition showed the two phase masses each close to 0.5, while a composition with a miniscule difference from this composition extrapolated to 1.0. The results showed spontaneous emulsification between solutions at the plait point and water to consist of two processes;an initial extremely fast reaction and a slower process between the aqueous phase formed in the primary emulsification and water.
基金Project supported by the National Natural Science Foundation of China(52074031)the Key Research and Development Program of Shandong Province(ZR2021MB051,ZR2020ME256)the Open Project of Key Laboratory of Green Chemical Engineering Process of Ministry of Education(GCP202117)。
文摘Solvent extraction is the main method used to separate and purify rare earth elements.In the process of rare earths extraction,emulsification often generated due to the instability of the aqueous and organic phases or improper operating conditions.Once emulsification occurs,it would not only lead to low rare earths recovery efficiency,small product quantities,high production costs and the losing of extractant and rare earth resources,but also result in serious environmental pollution.Therefore,it is very important to study the micro-mechanisms of emulsification and establish new methods to prevent emulsification at the source.In this paper,possible factors resulting in emulsification,such as the compositions and properties of the organic and aqueous phases,the operating conditions of the rare earths extraction are reviewed.The micro-mechanisms of emulsification are summarized basing on the microscopic structures in the bulk phase,aggregations of the extractants at the organic-aqueous interface,spectral characterizations and computational simulations.On this basis,new formation mechanisms are proposed for emulsification.Preliminary explorations are employed to verify the correctness of these new viewpoints.Finally,future directions for studies of the emulsification micro-mechanism are proposed.This study provides a theoretical basis for further understanding the micro-mechanisms of interfacial instability resulting in emulsification in the process of rare earths extraction.
基金Financial support from the National Key Research and Development Program (2024YFA1510003)the National Natural Science Foundation (U24B20197,22278209,U23A20117,22178165,22208149)+1 种基金the Jiangsu Province Natural Science Foundation(BK20220354)the State Key Laboratory of Materials-Oriented Chemical Engineering (SKL-MCE-23A11) of China are gratefully acknowledged。
文摘Emulsions are widely used across various industries but often require surfactants for stabilization,leading to complex product formulations and environmental concerns.Continuous preparation of stable emulsions without surfactants is still a significant challenge.Herein,a secondary membrane emulsification system was developed to produce stable oil-in-water emulsions under surfactant-free conditions,where the first membrane module employed the cross-flow membrane emulsification to generate the primary emulsion,while the second membrane module employed the premix membrane emulsification to further reduce the droplet size,thereby improving the emulsion stability.The morphology and droplet size of the secondary emulsion significantly depend on the membrane pore size,membrane surface wettability,primary emulsion flow,and primary emulsion quality.The secondary membrane emulsification system demonstrates excellent operational stability over 12 h,with no obvious changes in the emulsion characteristics.The prepared secondary emulsion remains relatively stable up to 10 min without surfactants,significantly superior to the primary emulsion.Furthermore,the developed system successfully produces the Janus emulsion with homogeneous internal phase morphology.This research provides an effective approach for the continuous preparation of stable emulsions without surfactants.
基金Supported by the Natural Science Foundation of Hebei Province(No.H2023206907).
文摘AIM:To elucidate the manifestations and associated complications observed in patients with intraocular silicone oil(SO)emulsification through multiple imaging modalities.METHODS:This single-center,observational,retrospective study included 116 patients who underwent pars plana vitrectomy(PPV)with SO injection for retinal detachment(RD),followed by subsequent SO removal at the Second Hospital of Hebei Medical University from January 2013 to January 2023.Comprehensive records of ophthalmic examinations utilizing multiple imaging techniques were maintained.RESULTS:The study comprised 56 females and 60 males,with a mean age of 52.75±13.6y.The mean follow-up duration for SO tamponade was 9.04±11.33mo(range:1-84mo).Among the participants,59 patients were diagnosed with SO emulsification,while 57 patients were in the SO unemulsified group.Patients with SO emulsification had a significantly prolonged SO tamponade duration(P<0.01).Multiple imaging techniques revealed notable signs of SO emulsification and its complications,such as 4 cases(3.4%)with posterior corneal SO-like keratic precipitates(KP)observed by anterior segment photography,23 cases(19.8%)exhibiting spherical high-reflection signals in the inter-retina,retinal pigment epithelium,or choroid detected by Spectralis spectral domain optical coherence tomography(SD-OCT),4 cases(3.4%)showing slow movement of emulsified SO droplets within retinal vessels during fluorescein angiography(FFA),plain and enhanced head magnetic resonance imaging(MRI)images of these four patients did not detect emulsified SO in the lateral ventricles,suprasellar cistern,subarachnoid space,third ventricle,fourth ventricle,or other intracranial locations.CONCLUSION:Intraocular emulsified SO can lead to damage in both anterior and posterior segment tissues,encompassing corneal degeneration,cataracts,glaucoma,retinal and choroid inflammation.Objective multiple imaging techniques such as anterior segment photography,SD-OCT,FFA,and MRI offer comprehensive evaluation and diagnosis of SO emulsification and its associated complications.
基金The Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.SJCX24-2440)the 2021 Zhenjiang sixth“169 project”scientific research projectthe 2023 Qinglan Project of Jiangsu Province,China。
文摘In the present study,an extended-release(ER)suspension of guanfacine hydrochloride(GFN)was successfully formulated using a self-synthesized cation-exchange resin characterized by a narrow particle size distribution.The drug-resin complex was prepared through a static adsorption method,employing the resin as a pharmaceutical carrier.Subsequently,guanfacine hydrochloride-coated microcapsules(GFN-CM)were fabricated via an emulsion solvent evaporation technique to achieve sustained-release functionality.Characterization revealed that the in-house resin exhibited a smoother surface and a narrower size distribution(Span value:0.74)compared to the commercial counterpart,Amberlite®IRP69.In vitro release studies demonstrated that the GFN-CM followed a zero-order kinetic model over 10 h,with a cumulative drug release of 81.88%observed at 12 h.Furthermore,pharmacokinetic evaluation in New Zealand rabbits showed that the mean residence time(MRT0–24)of the GFN suspension extended from 7.619 to 8.336 h,displaying a more stable plasma concentration-time profile and an average relative bioavailability(Fr)of 111.36% compared to marketed ER GFN tablets.These findings highlighted the successful development of a novel cation exchange resin-based delivery system,offering a promising strategy for enhancing the performance of ER pharmaceutical formulations.
基金Project supported by National Natural Science Foundation of China(50974042,51104040,51274060)the National Program on Key Basic Research Project of China(973 Program,2012CBA01205)+1 种基金the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2012BAE01B00)the Scientific Research Special Foundation of Doctor Subject of Chinese Universities(20100042110008)
文摘Emulsification troubled normal extraction process of rare earths due to the existence of non-rare earth impurities, especially Si, Al and Fe. Against this background, the effect of emulsification caused by Si, Al and Fe on the La extraction with saponification P507 (2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester) in chloride medium was systematically investigated. A series of experiments were carried out to study the relationship of the extraction capacity of La and the concentration of impurities. ZPM-203 polarizing microscope was applied to investigate the morphology of emulsification, and the cation exchange extraction mechanism of Fe and Al as well as La was clarified by IR spectra. The results showed that a low concentration of Si in organic phase would aggravate the emulsification with Al, and the formation of ME (micro emulsion) and club-shaped polymer would result in emulsification in the extraction of mixtures of Si and Al, single Fe, respectively. Furthermore, the accumulation of impurity such as Si, Al and Fe in the organic phase would severely reduce the extraction capacity of La simultaneously.
基金This project is supported by NSF of China(Nos. 20104008 and 29774038)State Key Laboratory of Polymer Physics and Chemistry.
文摘In this review, our recent work in phase inversion emulsification (PIE) for polymer (especially epoxy resin) waterborne dispersions is summarized. Based on experimental results about PIE process, the physical model is proposed which can guide the synthesis of the waterborne dispersions such as polymer/nanoparticle composite dispersion. In the presence of a latent curing catalyst, PIE can give a crosslinkable epoxy resin waterborne dispersion. The dispersions can form cured transparent coatings with some unique properties such as UV shielding. They are promising in functional coatings, waterborne resin matrices for composites, and sizing for high performance fibers.
文摘The aim of this study is to report and analyze the factors related with earlier occurrence of silicone oil(SO) emulsification in patients underwent pars plana vitrectomy and SO injection in our hospital. We retrospectively reviewed consecutive case series undergone both SO injection and removal in our hospital, and 182 ones were eligible. Possible related independent factors included: macula status(on/off), concomitant phacoemulsification with the surgery of SO tamponading, concomitant status of proliferative vitreoretinopathy, combined surgery of retinotomy, time to have emulsification(<6 mo/≥6 mo after primary SO injection), route of SO injection(anterior/posterior), lens status(aphakic/pseudophakic/phakic), anesthesia(local/general), brands and type of SO, with/without episcleral cryotherapy, with/without hypertension, with/without diabetes, with/without intraoperative use of triamcinolone acetonide. The study revealed that brand and type of SO was the significant factor related with earlier emulsification of SO. Further study was warranted to find out the underlying causes.
基金Natural Science Foundation of China for its financial support(grant number:U1762218)
文摘Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)process.However,field trials have shown that low concentration surfactant flooding can also improve oil recovery without ultra-low IFT.To clarify the mechanism behind,the currently-used surfactant,naphthenic arylsulfonate(NAS),was used to unravel its function during surfactant flooding from the horizon of micron-and nano-scale.The solubilization capacity of NAS micelle to petroleum fractions was evaluated through light absorbance strategy,smallangle neutron scattering,dynamic light scattering and transmission electron microscopy.It was found that micellar solubilization plays a significant role during the surfactant flooding.In-situ emulsification was visualized in microfluidics with three types of microchips,respectively.A series of displacement tests were carried out with NAS solution pumping into oil-saturated chip.The results show that in-situ emulsification improve oil recovery mainly through blocking and entrainment effects.Results from this work aid in understanding the interaction between surfactant solution and petroleum fractions at low surfactant concentration,which is helpful for design surfactant-based displacing system for EOR process.
基金Project supported by the National Natural Science Foundation of China (50974042)Scientific Research Special Foundation of Doctor Subject of Chinese Universities (20090042120015)the Fundamental Research Funds for the Central Universities (N090302007)
文摘P507 solvent extraction is the main method to separate and purify the rare earth products.The emulsification may be caused by the impurities in process of extracting rare earths,and these result in huge economic loss and decrease the quality of rare earth products.In recent researches,the extractant was prone to emulsification,and aluminum content of rare earth products also increased,while aluminum concentration of feed was higher.Pointing to this problem,the structural change of saponification P507 extracting aluminum and lanthanum was investigated by infrared spectroscopy,and the results showed that Al ions exchanged with H of P-O-H to become P-O-Al.Because aluminum held the characteristic of hydrophilic after extracted in the form of hydroxyl polymer ions and this provided conditions for the formation of micro emulsion.The organic phase and aqueous phase were investigated by polarizing microscope after aluminum was extracted.The results showed that the organic phase was clear when the extraction capacity of Al was less than 5 g/L.If the extraction capacity of Al exceeded 5 g/L,it formed W/O of ME(micro emulsion),leading to form emulsion of the organic phase.When Al concentration of feed was less than 1 g/L,the aqueous phase would form O/W of ME.If aluminum was extracted by saponification P507 firstly,then the the organic phase loading aluminum extracted rare earth continually,the organic and aqueous phase formed emulsification easily.
基金Supported by the Natural Science Foundation of Guangdong Province of China(No.2018A030310232,18zxxt72).
文摘AIM:To investigate the rates of emulsification in silicone oil(SO)tamponades of differing viscosities used during pars plana vitrectomy(PPV)in the treatment of complicated vitreoretinal diseases.METHODS:This study was a prospective randomized clinical trial.Totally 290 cases with greater likelihoods of secondary detachment were included and randomly grouped into either Siluron 2000(n=143)or Siluron 5000(n=147)SO tamponades with 23-gauge PPV.Patient followups and data analyses were conducted 1,3,6,and 12 mo post-surgery.RESULTS:The time of the SO emulsification ranged from 1 to 17 mo,with a mean of 7.3±4.2 mo.The Siluron 5000 group showed a slower emulsification rate in comparison to the Siluron 2000 group.The Siluron 2000 group took a shorter time to show signs of emulsification,necessitating earlier SO removal.However,there were no significant differences in the occurrence of complications,including secondary retinal detachment,cataract,corneal abnormality,high intraocular pressure and hypotony.CONCLUSION:The Siluron 2000 SO tamponade shows a faster rate of emulsification than the Siluron 5000 SO,necessitating earlier removal.Both groups show similar results in terms of anatomical success and visual acuity outcome,and there is no significant difference between the SOs regarding the occurrence of complications.
基金Supported by the National Natural Science Foundation of China(No.41576032)the Major Program for the International Cooperation of the Chinese Academy of Sciences,China(No.133337KYSB20160002)partially supported by the National Natural Science Foundation of China(Nos.41576170,61371189)
文摘The emulsification of crude oil is caused by the oil flowing into the water,resulting in the increase of oil film tension,viscosity,water content,and volume,which brings great harm to the marine ecological environment and difficulties for the cleanup of marine emergency equipment.The realization observation of emulsification crude oil will increase the response speed of marine emergency response.Therefore,we set up crude oil emulsification samples to study the physical property in laboratory and conducted radar measurements at different incidence angles in outdoor.The radar is C band in resolution of 0.7 m by 0.7 m.A fully polarimetric scatterometer(HH,VV,and VH/HV)is mounted at 1.66 m(minimum altitude)height at an incidence angle between 35°and 60°.An asphalt content of less than 3%crude oil and the filtered seawater were used to the outdoor emulsification scattering experiment.The measurement results are as follows.The water content can be used to describe the process of emulsification and it is easy to measure.Wind speed,asphalt content,seawater temperature,and photo-oxidation affect the emulsifying process of crude oil,and affects the normalized radar cross section(NRCS)of oil film but wind is not the dominant factor.It is the first time to find that the emulsification of crude oil results in an increase of NRCS.
基金The project supported by the Knowledge Innovation Project of the Chinese Academy of Sciences(No. KSCX2-SW-324)
文摘As reported in this paper, a strain of oil-degrading bacterium Sp - 5 - 3 was determined to belong to Enterobacteriaceae, which would be useful for microbial enhanced oil recovery (MEOR). The aim of our study was to generate a mutant using low energy N+ beam implantation. With 10 keV of energy and 5.2× 1014 N+/cm2 of dose - the optimum condition, a mutant, S-34, was obtained, which had nearly a 5-fold higher surface and a 13-fold higher of emulsifica-tion activity than the wild type. The surface activity was measured by two methods, namely, a surface tension measuring instrument and a recording of the repulsive circle of the oil film; the emulsification activity was scaled through measuring the separating time of the oil-fermentation mixture. The metabolic acid was determined as methane by means of gas chromatography.
基金The authors would like to acknowledge the Bu Ali Sina University and the Iran National Science Foundation:INSF,under Grant number of 99031559,for their financial supports.
文摘Surface active ionic liquids (SAILs) are considered as prominent materials in enhanced oil recovery thanks to their high interfacial activity. This study reports the preparation and applications of a nanostructure Tripodal imidazolium SAIL as an environmentally-friendly substitute to the conventional surfactants. The product has a star-like molecular structure centered by a triazine spacer, namely [(C_(4)im)_(3)TA][Cl_(3)], prepared by a one-step synthesis method and characterized with FT-IR, NMR, XRD, and SEM analysis methods. The interfacial tension of the system was decreased to about 78% at critical micelle concentration of less than 0.08 mol·dm^(−3). Increasing temperature, from 298.2 to 323.2 K, improved this capability. The solid surface wettability was changed from oil-wet to water-wet and 80% and 77% stable emulsions of crude oil–aqueous solutions were created after one day and one week, respectively. Compared to the Gemini kind homologous SAILs, the superior effects of the Tripodal SAIL were revealed and attributed to the strong hydrophobic branches in the molecule. The Frumkin adsorption isotherm precisely reproduced the generated IFT data, and accordingly, the adsorption and thermodynamic parameters were determined.
基金Supported by the National High Technology Research and Development Program of China (863 program, No.2006AA03Z534), the Postdoctoral Science Foundation of China (No.20060400927), the National Basic Research Program of China (No.2003CB6157070), the National Natural Science Foundation of China (No.20436030), Natural Science Foundation of Jiangsu Province (No.BK2006566), and Jiangsu Planned Projects for Postdoctoral Research Funds (No.0601023B).
文摘A novel method to prepare macroporous TiO2 ceramic, based on membrane emulsification was reported.To solve the paradox between the instability of nonaqueous emulsion and long emulsification time required by themembrane emulsification, a two-stage ceramic membrane jet-flow emulsification .was. proposed. Discussion wasconducted on the evolution of droplet size with time, which followed the Ostwalcl npemng theory. And a monodispersed nonaqueous emulsion with an average droplet size of 1.6μm could beprepared. Using the emulsion, as atemplate, TiO2 ceramics with an average pore size ot 1.1 μm were obtaineed. Tne material could be prospectivelyused for preparation of catalysts, adsorbents, and membranes.
文摘This research studied the initiator efficiency for producing polymeric particles of poly(styrene-co-methyl methacrylate)copolymers by a Shirasu porous glass membrane(SPG)emulsification technique followed by suspension copolymerization.BPO,ADVN,and AIBN were used as initiators and we found that BPO is the most suitable initiator.Copolymers for various feed ratios of styrene/methyl methacrylate were thus synthesized by benzoyl peroxide,and their copolymer particle size,molecular weight distribution and pat-ride size distribution were characterized.Then n-BMA or 2-EHMA was added as the third monomer to decrease the terpolymer glass transition temperature.This article describes the preparation technique,recipes and polymerization conditions for producing both copolymer and terpolymer particles,particle size changes,the corresponding particle morphologies and glass transition temperatures.
基金This project was supported by the National Natural Science Foundation of China (No. 20490220)Major State Basic Research Projects (No. 2003CB615604), Shengli Oilfield, SINOPEC.
文摘The mechanism of phase inversion emulsification process (PIE) was studied for waterborne dispersion of highly viscous epoxy resin using non-ionic polymeric surfactants. Drop deformation and breakup, rheological properties, conductivity, and particle size measurements reveal the micro-structural transition amid emulsification. It is revealed that strong flow causes water drop to burst with the formation of droplets and huge interface. Phase inversion corresponds to an abrupt rheological transition from a type of viscous melt with weak elasticity to a highly elastic type of aqueous gel. This implies that the phase inversion equivalent to a curvature inversion. Based on this, a geometric model is postulated to correlate process variables to the particle size. The coverage and conformation of the surfactant plays key role for the particle size of the final emulsion. The interactions of thermodynamic and hydrodynamic effects are also discussed. It is concluded that the thermodynamics control the PIE while the hydrodynamics drives the creation of interface and involves every step of PIE.