Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protectio...Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protection of marine environments.However,the spectrum of oil emulsions changes due to different water content.Hyperspectral remote sensing and deep learning can use spectral and spatial information to identify different types of oil emulsions.Nonetheless,hyperspectral data can also cause information redundancy,reducing classification accuracy and efficiency,and even overfitting in machine learning models.To address these problems,an oil emulsion deep-learning identification model with spatial-spectral feature fusion is established,and feature bands that can distinguish between crude oil,seawater,water-in-oil emulsion(WO),and oil-in-water emulsion(OW)are filtered based on a standard deviation threshold–mutual information method.Using oil spill airborne hyperspectral data,we conducted identification experiments on oil emulsions in different background waters and under different spatial and temporal conditions,analyzed the transferability of the model,and explored the effects of feature band selection and spectral resolution on the identification of oil emulsions.The results show the following.(1)The standard deviation–mutual information feature selection method is able to effectively extract feature bands that can distinguish between WO,OW,oil slick,and seawater.The number of bands was reduced from 224 to 134 after feature selection on the Airborne Visible Infrared Imaging Spectrometer(AVIRIS)data and from 126 to 100 on the S185 data.(2)With feature selection,the overall accuracy and Kappa of the identification results for the training area are 91.80%and 0.86,respectively,improved by 2.62%and 0.04,and the overall accuracy and Kappa of the identification results for the migration area are 86.53%and 0.80,respectively,improved by 3.45%and 0.05.(3)The oil emulsion identification model has a certain degree of transferability and can effectively identify oil spill emulsions for AVIRIS data at different times and locations,with an overall accuracy of more than 80%,Kappa coefficient of more than 0.7,and F1 score of 0.75 or more for each category.(4)As the spectral resolution decreasing,the model yields different degrees of misclassification for areas with a mixed distribution of oil slick and seawater or mixed distribution of WO and OW.Based on the above experimental results,we demonstrate that the oil emulsion identification model with spatial–spectral feature fusion achieves a high accuracy rate in identifying oil emulsion using airborne hyperspectral data,and can be applied to images under different spatial and temporal conditions.Furthermore,we also elucidate the impact of factors such as spectral resolution and background water bodies on the identification process.These findings provide new reference for future endeavors in automated marine oil spill detection.展开更多
Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present si...Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant challenges.In this study,we report a CFM@UiO-66-NH_(2)membrane with high separation flux,efficiency and stability,through utilizing a robust anti-abrasion collagen fiber membrane(CFM)as the multifunctional support and UiO-66-NH_(2)by an in-situ growth as the separation layer.The high mechanical strength of the CFM compensated for the weakness of the separation layer,while the charge-breaking effect of UiO-66-NH_(2),along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers,contributed to the potential for efficient separation.Additionally,the CFM@UiO-66-NH_(2)membrane exhibited superhydrophilic properties,making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic surfactants.The membrane demonstrated remarkable separation efficiencies of up to 99.960%and a separation flux of370.05 L·m^(-2)·h^(-1).Moreover,it exhibits stability,durability,and abrasion resistance,maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and performance.After six cycles of reuse,it achieved a separation flux of 417.97 L·m^(-2)·h^(-1)and a separation efficiency of 99.747%.Furthermore,after undergoing 500 cycles of strong abrasion,the separation flux remained at 124.39 L·m^(-2)·h^(-1),with a separation efficiency of 99.992%.These properties make it suitable for the long-term use in harsh operating environments.We attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH_(2)and its in-situ growth on the CFM,which forms a size-screening separation layer.Our work highlights the potential of the CFM@UiO-66-NH_(2)membrane as an environmentally friendly size-screening material for the efficient emulsion wastewater separation.展开更多
Although hydrophilic membranes are desired for reducing resistance to water permeation, hydrophilic surfaces are not used in the water-in-oil(W/O) membrane emulsification process because water spreads on the hydrophil...Although hydrophilic membranes are desired for reducing resistance to water permeation, hydrophilic surfaces are not used in the water-in-oil(W/O) membrane emulsification process because water spreads on the hydrophilic surface without forming droplets. Here, we report that a hydrophilic ceramic membrane can form a hydrophobic interface in diesel at a higher temperature;interestingly, the experiments show that the contact angle increases when the temperature rises. The hydrophilic membrane surface evolves into a hydrophobic interface, particularly near the boiling point of water, resulting in a water contact angle of 147.5° ± 1.2°. This work established a method for preparing W/O monodispersed emulsions by direct emulsification of hydrophilic ceramic membranes at a temperature close to the boiling point of water.Additionally, it made high flux of membrane emulsification of monodispersed W/O emulsions possible,which satisfied the industrial requirements of fluidized catalytic cracking in the petrochemical industry.展开更多
An improved rheo-optic in situ synchronous measurement system was employed to investigate the gelation behaviour and mechanism of waxy crude oil emulsions. By combining transmitted natural light and reflected polarize...An improved rheo-optic in situ synchronous measurement system was employed to investigate the gelation behaviour and mechanism of waxy crude oil emulsions. By combining transmitted natural light and reflected polarized light microscopy, a multiangle composite light source was built to achieve the simultaneous observation of wax crystals and emulsified water droplets, as well as their dynamic aggregation process. Main outcomes on the microscopic mechanism were obtained by developed microscopic image processing method. It was found that the microstructure of W/O waxy crude oil emulsion has the evolution of “individual structure--homogeneous aggregate structure--heterogeneous coaggregate structure--floc structure” during the static cooling, which results in the four stages during gelation process. Different from previous studies, the aggregation of emulsified water droplets was found to be more significant and contributes to the formation and development of the wax crystals-emulsified water droplets coaggregate, which plays a decisive role in the further evolution of the gelled microstructure. Time series microscopic images show the dynamic aggregation of emulsified water droplets and wax crystals. Two different aggregation behaviours between wax crystals and water droplets were observed. That wax crystals can not only embed in gaps between adjacent water droplets and enhance the structure, but also surround the outside of the water droplets and continue to grow resulting in the interconnection of different coaggregates to form a larger floc structure. In addition, correlation between viscoelasticity and microstructure evolution of waxy crude oil emulsions of different water contents was discussed. With increasing water contents, the microstructure is changed from wax crystal flocculation structure as the main skeleton and the emulsified water droplets embedded in it, into the aggregation of emulsified water droplets occupying the main position. When the number of wax crystals and water droplets reaches a certain ratio, did wax crystals form coaggregates with emulsified water droplets, and the remaining wax crystals formed an overall flocculation structure, the viscoelasticity of the waxy crude oil emulsion is the highest.展开更多
In recent years,Pickering emulsions and their applications have attracted a great deal of attention due to their special features,which include easy preparation and enhanced stability.In contrast to classical emulsion...In recent years,Pickering emulsions and their applications have attracted a great deal of attention due to their special features,which include easy preparation and enhanced stability.In contrast to classical emulsions,in Pickering emulsions,solid microparticles or nanoparticles that localize at the interface between liquids are used as stabilizers,instead of surfactants,to enhance the droplet lifetime.Furthermore,Pickering emulsions show higher stability,lower toxicity,and stimuli-responsiveness,compared with emulsions that are stabilized by surfactants.Therefore,they can be considered attractive components for various uses,such as photocatalysis and the preparation of new materials.Moreover,the nanoparticle morphology strongly influences Pickering emulsion stability as well as the potential utilization of such emulsions.Here,we review recent findings concerning Pickering emulsions,with a particular focus on how the nanoparticles morphology(i.e.,cube,ellipsoid,nanosheet,sphere,cylinder,rod,peanut)influences the type and stability of such emulsions,and their current applications in different fields such as antibacterial activity,protein recognition,catalysis,photocatalysis,and water purification.展开更多
The aim of this study was to investigate the effect of high-pressure homogenization on the droplet size and physical stability of different formulations of pectin–zein stabilized rice bran oil emulsions. The obtained...The aim of this study was to investigate the effect of high-pressure homogenization on the droplet size and physical stability of different formulations of pectin–zein stabilized rice bran oil emulsions. The obtained emulsions, both before and after passing through highpressure homogenizer, were subjected to stability test under environmental stress conditions,that is, temperature cycling at 4 °C/40 °C for 6 cycles and centrifugal test at 3000 rpm for 10 min. Applying high-pressure homogenization after mechanical homogenization caused only a small additional decrease in emulsion droplet size. The droplet size of emulsions was influenced by the type of pectin used;emulsions using high methoxy pectin(HMP) were smaller than that using low methoxy pectin(LMP). This is due to a greater emulsifying property of HMP than LMP. The emulsions stabilized by HMP–zein showed good physical stability with lower percent creaming index than those using LMP, both before and after passing through high-pressure homogenizer. The stability of emulsions after passing through high-pressure homogenizer was slightly higher when using higher zein concentration, resulting from stronger pectin–zein complexes that could rearrange and adsorb onto the emulsion droplets.展开更多
Macromolecules of polysaccharides, proteins and poloxamers have a hydrophobic portion and a hydrophilic one that can be used as emulsifiers. Parts of these emulsifiers are safe pharmaceutical excipients, which can rep...Macromolecules of polysaccharides, proteins and poloxamers have a hydrophobic portion and a hydrophilic one that can be used as emulsifiers. Parts of these emulsifiers are safe pharmaceutical excipients, which can replace the irritant low molecular weight surfactants to formulate emulsions for the pharmaceutical field. This project focused on preparing O/W emulsions stabilized with polymers for pharmaceuticals such as polysaccharides, proteins and poloxamers, including hydroxypropyl methylcellulose (HPMC), methylcellulose (MC),gelatin, poloxamer 407 (F127) and poloxamer 188 (F68). Emulsion physical stability was assessed by centrifugation, autoclaving sterilization and droplet size measurements. The stabilization mechanisms of emulsions were determined by interfacial tension and rheological measurements. Results stated that the efficacy of these polymers for pharmaceuticals stabilized emulsions was sorted in the order: F127 > F68 > HPMC > MC > Gelatin.展开更多
Responsive emulsions are the emulsions that can be reversibly switched on-demand between“stable”and“unstable”by environmental stimulus or trigger,which allows a simple and effective adjustment approach to achieve ...Responsive emulsions are the emulsions that can be reversibly switched on-demand between“stable”and“unstable”by environmental stimulus or trigger,which allows a simple and effective adjustment approach to achieve emulsification and demulsification.In recent years,stimuli-responsive emulsions acting as smart soft material are received considerable attention with the advantages of simple manipulation,good reversibility,low cost,easy treatment,and little effect on the system.In this paper,the recent research progress of emulsions that can respond to external stimuli,including pH,light,magnetic field,CO_(2)/N_(2) and dual responsive are reviewed.Also,the potential applications based on responsive emulsion are discussed,such as catalytic reactions,heavy oil recovery,polymer particles synthesis and optical sensor,aiming to summarize the latest achievements and put forward the possible development trends of responsive emulsions.展开更多
A novel and high-efficiency coalescence membrane enhanced by nano-sized polyvinylidene fluoride(PVDF)nanofibers based on polyester(PET)substrate was fabricated using electrospinning method.The properties of the electr...A novel and high-efficiency coalescence membrane enhanced by nano-sized polyvinylidene fluoride(PVDF)nanofibers based on polyester(PET)substrate was fabricated using electrospinning method.The properties of the electrospun nanofibers such as roughness and surface morphology greatly affected the oil droplet interception efficiency and surface wettability of the membrane.A series of coalescence units were prepared with different layers of nanofibrous membrane and the separation efficiencies at different initial concentrations,flow rates,and oil types were tested.It is very interesting that the obtained nanofibrous membrane exhibited superoleophilicity in air but poor oleophilicity under water,which was beneficial to the coalescence process.The coalescence unit with four membrane layers had excellent performances under different initial concentrations and flow rates.The separation efficiency of the 4-layers unit remained above 98.2%when the initial concentration reached up to 2000 mg·L-1.Furthermore,the unit also exhibited good performance with the increasing oil density and viscosity,which is promising for large-scale oil wastewater treatment.展开更多
In well stimulation treatments using hydrochloric acid,undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development.The processes intensify in the presence...In well stimulation treatments using hydrochloric acid,undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development.The processes intensify in the presence of Fe(Ⅲ),which are from the corroded surfaces of field equipment and/or iron-bearing minerals of the oil reservoir.In order to understand the reasons of the stability of acid emulsions,acid emulsions were prepared by mixing crude oil emulsion with 15% hydrochloric acid solutions with and without Fe(Ⅲ) and then separated into free and upper(water free) and intermediate(with water) layers.It is assumed that the oil phase of the free and upper layers contains the compounds which do not participate in the formation of acid emulsions,and the oil phase of the intermediate layers contains components involved in the formation of oil/acid interface.The composition of the oil phase of each layer of the emulsions was studied.It is found that the asphaltenes with a high content of sulfur,oxygen and metals as well the flocculated material of protonated non-polar oil components are concentrated at the oil/acid interface.In addition to the above,in the presence of Fe(Ⅲ) the Fe(Ⅲ)-based complexes with polar groups of asphaltenes are formed at the acid/oil interface,contributing to the formation of armor films which enhance the emulsion stability.展开更多
Pharmaceutical delivery systems are developed to improve the physicochemical properties of therapeutic compounds. Emulsions are one of these drug delivering systems formulated using water, oils and lipids as main ingr...Pharmaceutical delivery systems are developed to improve the physicochemical properties of therapeutic compounds. Emulsions are one of these drug delivering systems formulated using water, oils and lipids as main ingredients. Extensive data are usually generated on the physical and chemical characteristics of these oil-in-water and lipid emulsions. However, the oxidative tendency of emulsions is often overlooked. Oxidation impacts the overall quality and safety of these pharmaceutical emulsions. Additionally, introducing oxidatively unstable emulsions into biological systems further promotes oxidation in situ. Products of these reactions then continue to pose serious harm to cells and fuel other physiological oxidation reactions. Consequently, the increase of oxidation products leads to oxidative damage to biological systems. Thus, emulsions with lower lipid peroxidation are more stable and will reduce the negative effects of oxidation in situ. Preventive measures during the formulation of emulsions are important. Many naturally occurring and cost effective substances possess low oxidation tendencies and confer oxidative protection when used in emulsions. Additionally,certain preparatory methods should be employed to reduce or better control lipid peroxidation.Finally, emulsions must be evaluated for their oxidation susceptibility using the various techniques available. Careful attention to the preparation of emulsions and assessment of their oxidative stability will help produce safer emulsions without compromising efficacy.展开更多
The effect of silica nanoparticles on the rheological characteristics of water-in-heavy oil emulsions has been investigated.Enhanced oil recovery methods for heavy oil production(most especially,thermal fluid injectio...The effect of silica nanoparticles on the rheological characteristics of water-in-heavy oil emulsions has been investigated.Enhanced oil recovery methods for heavy oil production(most especially,thermal fluid injection)usually result in the formation of water-in-oil(W/O)emulsion.In reality,the emulsion produced also contains some fine solid mineral particles such as silica,which,depending on its quantity,may alter the viscosity and/or rheological properties of the fluid.A series of binary-component emulsions were separately prepared by dispersing silica nanoparticles[phase fraction,βs,=0.5%–5.75%(wt/v)]in heavy oil(S/O suspension)and by dispersing water[water cut,θw=10%–53%(v/v)]in heavy oil(W/O emulsion).Ternary-component emulsions comprising heavy oil,water droplets and suspended silica nanoparticles(S/W/O)were also prepared with similar ranges ofθw andβs.The viscosity was measured at different shear rates(5.1–1021.4 s-1)and temperatures(30–70°C).Both binary-component and ternary-component emulsion systems were observed to exhibit nonNewtonian shear thinning behaviour.The viscosity of the heavy oil and W/O emulsions increased in the presence of silica nanoparticles.The effect was,however,less signifi cant belowβs=2%(wt/v).Moreover,a generalized correlation has been proposed to predict the viscosity of both binary-component and ternary-component emulsions.展开更多
Interfacial properties rhamnolipids from an extract produced by a strain of Pseudomonas aeruginosa were analyzed in this study. The extract of rhamnolipid was characterized by surface tension in different conditions;i...Interfacial properties rhamnolipids from an extract produced by a strain of Pseudomonas aeruginosa were analyzed in this study. The extract of rhamnolipid was characterized by surface tension in different conditions;interfacial tension with different hydrocarbons;critical micelle concentration under different pH and temperatures;particle size and emulsification capacity using laser light profiling. It was observed that the rhamnolipids extract are sensitive to variations in pH, thermostable and function as good emulsificant for emulsification of methyl methacrylate. The emulsion stability order in function of the oil phase was methyl methacrylate > emulsions of castor oil > emulsion n-heptane > emulsion toluene > emulsion hexadecane > octane emulsion. The data presented show that rhamnolipid extracts may be used to formulate stable emulsions of methyl methacrylate. This process can be used to do nano/microsphere of polymethyl methacrylate.展开更多
Alkenyl succinic anhydride(ASA) is a popular paper-sizing agent that is generally added to papermaking systems as an aqueous emulsion. Herein, we reviewed the recent work focusing on ASA emulsions stabilized by solid ...Alkenyl succinic anhydride(ASA) is a popular paper-sizing agent that is generally added to papermaking systems as an aqueous emulsion. Herein, we reviewed the recent work focusing on ASA emulsions stabilized by solid particles. Solid particle-stabilized ASA emulsions generally possess high ASA content and exhibit good sizing performance. The particles that have been used to stabilize ASA emulsions typically include montmorillonite, laponite, alumina, TiO_2, Fe_3O_4, polyaluminum sulfate(PAS), and cellulose nanocrystals(CNCs). Montmorillonite is the first extensively studied particle stabilizer for ASA emulsions. Laponite is undoubtedly the most competent particle stabilizer for preparing ASA emulsions with high sizing efficiency. Montmorillonite and laponite can be used individually as stabilizers after modification or as co-stabilizers with other particles or polymers. TiO_2, alumina, PAS, and CNCs are commonly used as stabilizers either individually or with other particles.展开更多
Enhancement of oxidative stability of canola oil extracted from seed subjected to prior heat-treatment has been attributed to heat-induced generation of antioxidants from phenolic precursors occurring in canola seed. ...Enhancement of oxidative stability of canola oil extracted from seed subjected to prior heat-treatment has been attributed to heat-induced generation of antioxidants from phenolic precursors occurring in canola seed. Dispersion of aqueous extracts of intact seed oil bodies (OBs) in water is a novel and interesting way of producing natural and oxidatively stable food emulsions with minimal use of synthetic antioxidants and emulsifiers. As there is growing interest in natural food emulsions containing unsaturated oils, we investigated whether the oxidative stability of canola OB emulsions could be further improved by subjecting canola seed to heat-treatment prior to oil body extraction. Oil-in-water (5%, w/w) emulsions of OBs extracted from canola seed before and after heat-treatment were considerably more resistant to oxidation than emulsions prepared from refined canola oil and Tween? 40 emulsifier. However, only small amounts (0.9% - 4.5% by weight) of the phenolic compounds present in canola seed were transferred to the OBs after aqueous extraction, and consequently there was no discernible effect on oxidative stability as a result of prior heat-treatment of the seed. Thus, in contrast to oil, there is no oxidative stability benefit to be gained by subjecting canola seed to heat-treatment prior to extraction of OBs.展开更多
With the advent of new, particularly mixed-oil lipid emulsions approved by the United States Food & Drug Administration (FDA), clinicians have more options when choosing one as part of the parenteral nutrition sup...With the advent of new, particularly mixed-oil lipid emulsions approved by the United States Food & Drug Administration (FDA), clinicians have more options when choosing one as part of the parenteral nutrition support of patients. Lipid products long-standing availability in Europe and other parts of the world has certainly facilitated the process in the United States, where there was little evolution before 2014. These newer oil-based emulsions are finding their way to be used in pediatrics, as studies are being carried out that will result in pediatric labeling. Pediatric clinicians may find themselves wondering how these lipid emulsions are different from those that have come before;whether the same dosing or administration practices apply as with the traditional soybean-oil lipid emulsion, and if they can be used for other more emergent interventions. We present this review of the current lipid emulsions available in the U.S. market, highlighting the differences among them, as well as, providing some practical information for clinicians that can assist them in their day-to-day duties.展开更多
In order to study the profile control characteristics of emulsions in porous medium, the heterogeneous experimental model was established, by which the experimental scheme was designed with different permeabilities, m...In order to study the profile control characteristics of emulsions in porous medium, the heterogeneous experimental model was established, by which the experimental scheme was designed with different permeabilities, matching degree of particle size and concentration of emulsions. Based on experimental results of physical simulation, the concept of distributing rate and changing coefficient was introduced to quantitatively evaluate the profile control characteristics of emulsions. The results of the study show that, as the permeability ratio and emulsion concentration increase, the profile control characteristics of emulsions will enhance. The profile control characteristics of emulsions will be the best. The profile control scheme with emulsions was implemented in Bohai X oil field, The research results can be used for reference to design the profile control scheme in Bohai heterogeneous reservoir.展开更多
Objective:The aim of this study was to discover the potential biomarkers changes on a rat model of isoproterenol (ISO) induced myocardial ischaemia before and after treatment with a Xiangdan submicron emulsion and to ...Objective:The aim of this study was to discover the potential biomarkers changes on a rat model of isoproterenol (ISO) induced myocardial ischaemia before and after treatment with a Xiangdan submicron emulsion and to explore the unclearing mechanisms by urinary metabolomics.Methods:Three active traditional Chinese medicine (TCM) ingredients were formulated into a lyophilized submicron emulsion powder with hydroxypropyl-β-cyclodextrin encapsulation by high pressure homogenization technology.The three ingredients were given both separately and combined,and the corresponding effects of the three drugs were compared.Principal component analysis (PCA) and the HPLC-UV analytical method was applied to explore the change of composition of urine metabolites in a rat model of isoproterenol induced myocardial ischaemia.Results:Analytical methods measuring the three active ingredients in urine samples were established.PCA score plots revealed that the therapeutic effect of the Xiangdan submicron emulsion was more significant than that of the Xiangdan injection.There was a synergistic effect among the three active ingredients.Furthermore,studies of rat metabolism changes and structure analysis of biological markers indicated that the mechanism of Xiangdan formulations was related to the inhibition of abnormal tryptophan metabolism.Conclusion:Xiangdan preparations had a confirmed effect in the treatment of coronary heart disease,especially with the novel Xiangdan submicron emulsion formulation.Urinary metabolomics methods to monitor special biomarker changes is an excellent method to reveal the mechanism of action of TCM drugs.展开更多
Cosmetic emulsions, as all macro emulsions, are inherently unstable systems, from a thermodynamic viewpoint. More specific eco-friendly oil/water (O/W) cosmetic emulsions are usually less stable than conventional ones...Cosmetic emulsions, as all macro emulsions, are inherently unstable systems, from a thermodynamic viewpoint. More specific eco-friendly oil/water (O/W) cosmetic emulsions are usually less stable than conventional ones as milder chemicals or less intense (energy consuming) production processes are involved. In this context, two traditional techniques an optical technique and a volumetric one have been used for the assessment of the stability of cosmetic emulsions and compared to each other. Eco-friendly cosmetic emulsions were produced with different olive oil/water extracts (Rosmarinus officinalis and Calendula officinalis extracts) and emulsifier (Glycerol monostearate, GMS) concentrations. Emulsions’ stability was registered simultaneously by 1) Microscopy photos of samples withdrawn at regular intervals from the test vessel;2) global volumetric measurements of the different phases (water/oil/emulsion) inside the test vessel made at regular intervals for determining the evolution of the location of the phases separation interface. Analysis of the results of each technique and comparisons among them are presented and discussed in detail.展开更多
Multiple emulsions are of great therapeutic interest especially in the administration of medicines which can be inactivated by digestive enzymes;moreover the researches of formulation not being often easy, a control o...Multiple emulsions are of great therapeutic interest especially in the administration of medicines which can be inactivated by digestive enzymes;moreover the researches of formulation not being often easy, a control of the different phases physicochemical parameters would be of great interest in rapid formulations and at low cost. When formulating emulsions, the preliminary tests, also known as formulation tests, constitute a step which can be long and expensive because of the quantity of reagents that can be used. A rigorous methodology could thus be of great interest, which is at the aim of our study which consists of evaluating the physico-chemical parameters of different phases used to make thus multiple emulsions. In our study, physico-chemical parameters such as conductivity, pH, density, viscosity, and surface tension have been studied by direct measurement using equipment and also by means of suitable mounting. The results showed that the pH and the surface tension have an important role in the prediction of the stability of emulsions, these latter must be of the same order of magnitude. For all phases conductivity does not have too much interest apart from helping to determine the type of the emulsion.展开更多
基金The National Natural Science Foundation of China under contract Nos 61890964 and 42206177the Joint Funds of the National Natural Science Foundation of China under contract No.U1906217.
文摘Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protection of marine environments.However,the spectrum of oil emulsions changes due to different water content.Hyperspectral remote sensing and deep learning can use spectral and spatial information to identify different types of oil emulsions.Nonetheless,hyperspectral data can also cause information redundancy,reducing classification accuracy and efficiency,and even overfitting in machine learning models.To address these problems,an oil emulsion deep-learning identification model with spatial-spectral feature fusion is established,and feature bands that can distinguish between crude oil,seawater,water-in-oil emulsion(WO),and oil-in-water emulsion(OW)are filtered based on a standard deviation threshold–mutual information method.Using oil spill airborne hyperspectral data,we conducted identification experiments on oil emulsions in different background waters and under different spatial and temporal conditions,analyzed the transferability of the model,and explored the effects of feature band selection and spectral resolution on the identification of oil emulsions.The results show the following.(1)The standard deviation–mutual information feature selection method is able to effectively extract feature bands that can distinguish between WO,OW,oil slick,and seawater.The number of bands was reduced from 224 to 134 after feature selection on the Airborne Visible Infrared Imaging Spectrometer(AVIRIS)data and from 126 to 100 on the S185 data.(2)With feature selection,the overall accuracy and Kappa of the identification results for the training area are 91.80%and 0.86,respectively,improved by 2.62%and 0.04,and the overall accuracy and Kappa of the identification results for the migration area are 86.53%and 0.80,respectively,improved by 3.45%and 0.05.(3)The oil emulsion identification model has a certain degree of transferability and can effectively identify oil spill emulsions for AVIRIS data at different times and locations,with an overall accuracy of more than 80%,Kappa coefficient of more than 0.7,and F1 score of 0.75 or more for each category.(4)As the spectral resolution decreasing,the model yields different degrees of misclassification for areas with a mixed distribution of oil slick and seawater or mixed distribution of WO and OW.Based on the above experimental results,we demonstrate that the oil emulsion identification model with spatial–spectral feature fusion achieves a high accuracy rate in identifying oil emulsion using airborne hyperspectral data,and can be applied to images under different spatial and temporal conditions.Furthermore,we also elucidate the impact of factors such as spectral resolution and background water bodies on the identification process.These findings provide new reference for future endeavors in automated marine oil spill detection.
基金supported by National Natural Science Foundation of China(22008035,22108040,22378066)Science and Technology Project of Environmental Protection in Fujian(2022R026)Natural Science Foundation of Fujian Province(2020J05131,2020J05130)。
文摘Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant challenges.In this study,we report a CFM@UiO-66-NH_(2)membrane with high separation flux,efficiency and stability,through utilizing a robust anti-abrasion collagen fiber membrane(CFM)as the multifunctional support and UiO-66-NH_(2)by an in-situ growth as the separation layer.The high mechanical strength of the CFM compensated for the weakness of the separation layer,while the charge-breaking effect of UiO-66-NH_(2),along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers,contributed to the potential for efficient separation.Additionally,the CFM@UiO-66-NH_(2)membrane exhibited superhydrophilic properties,making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic surfactants.The membrane demonstrated remarkable separation efficiencies of up to 99.960%and a separation flux of370.05 L·m^(-2)·h^(-1).Moreover,it exhibits stability,durability,and abrasion resistance,maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and performance.After six cycles of reuse,it achieved a separation flux of 417.97 L·m^(-2)·h^(-1)and a separation efficiency of 99.747%.Furthermore,after undergoing 500 cycles of strong abrasion,the separation flux remained at 124.39 L·m^(-2)·h^(-1),with a separation efficiency of 99.992%.These properties make it suitable for the long-term use in harsh operating environments.We attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH_(2)and its in-situ growth on the CFM,which forms a size-screening separation layer.Our work highlights the potential of the CFM@UiO-66-NH_(2)membrane as an environmentally friendly size-screening material for the efficient emulsion wastewater separation.
基金the support from the National Key Research and Development Program of China (2021YFB3801303)the National Natural Science Foundation of China (21838005, 21921006)the Key Scientific Research and Development Projects of Jiangsu Province (BE201800901)。
文摘Although hydrophilic membranes are desired for reducing resistance to water permeation, hydrophilic surfaces are not used in the water-in-oil(W/O) membrane emulsification process because water spreads on the hydrophilic surface without forming droplets. Here, we report that a hydrophilic ceramic membrane can form a hydrophobic interface in diesel at a higher temperature;interestingly, the experiments show that the contact angle increases when the temperature rises. The hydrophilic membrane surface evolves into a hydrophobic interface, particularly near the boiling point of water, resulting in a water contact angle of 147.5° ± 1.2°. This work established a method for preparing W/O monodispersed emulsions by direct emulsification of hydrophilic ceramic membranes at a temperature close to the boiling point of water.Additionally, it made high flux of membrane emulsification of monodispersed W/O emulsions possible,which satisfied the industrial requirements of fluidized catalytic cracking in the petrochemical industry.
文摘An improved rheo-optic in situ synchronous measurement system was employed to investigate the gelation behaviour and mechanism of waxy crude oil emulsions. By combining transmitted natural light and reflected polarized light microscopy, a multiangle composite light source was built to achieve the simultaneous observation of wax crystals and emulsified water droplets, as well as their dynamic aggregation process. Main outcomes on the microscopic mechanism were obtained by developed microscopic image processing method. It was found that the microstructure of W/O waxy crude oil emulsion has the evolution of “individual structure--homogeneous aggregate structure--heterogeneous coaggregate structure--floc structure” during the static cooling, which results in the four stages during gelation process. Different from previous studies, the aggregation of emulsified water droplets was found to be more significant and contributes to the formation and development of the wax crystals-emulsified water droplets coaggregate, which plays a decisive role in the further evolution of the gelled microstructure. Time series microscopic images show the dynamic aggregation of emulsified water droplets and wax crystals. Two different aggregation behaviours between wax crystals and water droplets were observed. That wax crystals can not only embed in gaps between adjacent water droplets and enhance the structure, but also surround the outside of the water droplets and continue to grow resulting in the interconnection of different coaggregates to form a larger floc structure. In addition, correlation between viscoelasticity and microstructure evolution of waxy crude oil emulsions of different water contents was discussed. With increasing water contents, the microstructure is changed from wax crystal flocculation structure as the main skeleton and the emulsified water droplets embedded in it, into the aggregation of emulsified water droplets occupying the main position. When the number of wax crystals and water droplets reaches a certain ratio, did wax crystals form coaggregates with emulsified water droplets, and the remaining wax crystals formed an overall flocculation structure, the viscoelasticity of the waxy crude oil emulsion is the highest.
文摘In recent years,Pickering emulsions and their applications have attracted a great deal of attention due to their special features,which include easy preparation and enhanced stability.In contrast to classical emulsions,in Pickering emulsions,solid microparticles or nanoparticles that localize at the interface between liquids are used as stabilizers,instead of surfactants,to enhance the droplet lifetime.Furthermore,Pickering emulsions show higher stability,lower toxicity,and stimuli-responsiveness,compared with emulsions that are stabilized by surfactants.Therefore,they can be considered attractive components for various uses,such as photocatalysis and the preparation of new materials.Moreover,the nanoparticle morphology strongly influences Pickering emulsion stability as well as the potential utilization of such emulsions.Here,we review recent findings concerning Pickering emulsions,with a particular focus on how the nanoparticles morphology(i.e.,cube,ellipsoid,nanosheet,sphere,cylinder,rod,peanut)influences the type and stability of such emulsions,and their current applications in different fields such as antibacterial activity,protein recognition,catalysis,photocatalysis,and water purification.
基金financially supported by the Research and Development Institute, Silpakorn University
文摘The aim of this study was to investigate the effect of high-pressure homogenization on the droplet size and physical stability of different formulations of pectin–zein stabilized rice bran oil emulsions. The obtained emulsions, both before and after passing through highpressure homogenizer, were subjected to stability test under environmental stress conditions,that is, temperature cycling at 4 °C/40 °C for 6 cycles and centrifugal test at 3000 rpm for 10 min. Applying high-pressure homogenization after mechanical homogenization caused only a small additional decrease in emulsion droplet size. The droplet size of emulsions was influenced by the type of pectin used;emulsions using high methoxy pectin(HMP) were smaller than that using low methoxy pectin(LMP). This is due to a greater emulsifying property of HMP than LMP. The emulsions stabilized by HMP–zein showed good physical stability with lower percent creaming index than those using LMP, both before and after passing through high-pressure homogenizer. The stability of emulsions after passing through high-pressure homogenizer was slightly higher when using higher zein concentration, resulting from stronger pectin–zein complexes that could rearrange and adsorb onto the emulsion droplets.
基金supported by the National Natural Science Foundation of China (No.81273445 and No.81473161)
文摘Macromolecules of polysaccharides, proteins and poloxamers have a hydrophobic portion and a hydrophilic one that can be used as emulsifiers. Parts of these emulsifiers are safe pharmaceutical excipients, which can replace the irritant low molecular weight surfactants to formulate emulsions for the pharmaceutical field. This project focused on preparing O/W emulsions stabilized with polymers for pharmaceuticals such as polysaccharides, proteins and poloxamers, including hydroxypropyl methylcellulose (HPMC), methylcellulose (MC),gelatin, poloxamer 407 (F127) and poloxamer 188 (F68). Emulsion physical stability was assessed by centrifugation, autoclaving sterilization and droplet size measurements. The stabilization mechanisms of emulsions were determined by interfacial tension and rheological measurements. Results stated that the efficacy of these polymers for pharmaceuticals stabilized emulsions was sorted in the order: F127 > F68 > HPMC > MC > Gelatin.
基金supported by the National Natural Science Foun-dation of China(21908026)the Fujian Province science and tech-nology guidance project(2021Y0007)Key Program of Qingyuan Innovation Laboratory(00221004).
文摘Responsive emulsions are the emulsions that can be reversibly switched on-demand between“stable”and“unstable”by environmental stimulus or trigger,which allows a simple and effective adjustment approach to achieve emulsification and demulsification.In recent years,stimuli-responsive emulsions acting as smart soft material are received considerable attention with the advantages of simple manipulation,good reversibility,low cost,easy treatment,and little effect on the system.In this paper,the recent research progress of emulsions that can respond to external stimuli,including pH,light,magnetic field,CO_(2)/N_(2) and dual responsive are reviewed.Also,the potential applications based on responsive emulsion are discussed,such as catalytic reactions,heavy oil recovery,polymer particles synthesis and optical sensor,aiming to summarize the latest achievements and put forward the possible development trends of responsive emulsions.
基金supported by the National Key Research and Development Program of China(No.2017YFB0308000)the National Natural Science Foundation of China(No.21706259)+3 种基金the State Key Laboratory of Heavy Oil Processing(SKLOP201903001)Guizhou Science Technology Support Program([2019]2839)the Natural Science Youth Foundation of Shanxi Province(No.201701D221033)Program of Innovation Academy for Green Manufacture,CAS(IAGM2020C04)。
文摘A novel and high-efficiency coalescence membrane enhanced by nano-sized polyvinylidene fluoride(PVDF)nanofibers based on polyester(PET)substrate was fabricated using electrospinning method.The properties of the electrospun nanofibers such as roughness and surface morphology greatly affected the oil droplet interception efficiency and surface wettability of the membrane.A series of coalescence units were prepared with different layers of nanofibrous membrane and the separation efficiencies at different initial concentrations,flow rates,and oil types were tested.It is very interesting that the obtained nanofibrous membrane exhibited superoleophilicity in air but poor oleophilicity under water,which was beneficial to the coalescence process.The coalescence unit with four membrane layers had excellent performances under different initial concentrations and flow rates.The separation efficiency of the 4-layers unit remained above 98.2%when the initial concentration reached up to 2000 mg·L-1.Furthermore,the unit also exhibited good performance with the increasing oil density and viscosity,which is promising for large-scale oil wastewater treatment.
文摘In well stimulation treatments using hydrochloric acid,undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development.The processes intensify in the presence of Fe(Ⅲ),which are from the corroded surfaces of field equipment and/or iron-bearing minerals of the oil reservoir.In order to understand the reasons of the stability of acid emulsions,acid emulsions were prepared by mixing crude oil emulsion with 15% hydrochloric acid solutions with and without Fe(Ⅲ) and then separated into free and upper(water free) and intermediate(with water) layers.It is assumed that the oil phase of the free and upper layers contains the compounds which do not participate in the formation of acid emulsions,and the oil phase of the intermediate layers contains components involved in the formation of oil/acid interface.The composition of the oil phase of each layer of the emulsions was studied.It is found that the asphaltenes with a high content of sulfur,oxygen and metals as well the flocculated material of protonated non-polar oil components are concentrated at the oil/acid interface.In addition to the above,in the presence of Fe(Ⅲ) the Fe(Ⅲ)-based complexes with polar groups of asphaltenes are formed at the acid/oil interface,contributing to the formation of armor films which enhance the emulsion stability.
文摘Pharmaceutical delivery systems are developed to improve the physicochemical properties of therapeutic compounds. Emulsions are one of these drug delivering systems formulated using water, oils and lipids as main ingredients. Extensive data are usually generated on the physical and chemical characteristics of these oil-in-water and lipid emulsions. However, the oxidative tendency of emulsions is often overlooked. Oxidation impacts the overall quality and safety of these pharmaceutical emulsions. Additionally, introducing oxidatively unstable emulsions into biological systems further promotes oxidation in situ. Products of these reactions then continue to pose serious harm to cells and fuel other physiological oxidation reactions. Consequently, the increase of oxidation products leads to oxidative damage to biological systems. Thus, emulsions with lower lipid peroxidation are more stable and will reduce the negative effects of oxidation in situ. Preventive measures during the formulation of emulsions are important. Many naturally occurring and cost effective substances possess low oxidation tendencies and confer oxidative protection when used in emulsions. Additionally,certain preparatory methods should be employed to reduce or better control lipid peroxidation.Finally, emulsions must be evaluated for their oxidation susceptibility using the various techniques available. Careful attention to the preparation of emulsions and assessment of their oxidative stability will help produce safer emulsions without compromising efficacy.
文摘The effect of silica nanoparticles on the rheological characteristics of water-in-heavy oil emulsions has been investigated.Enhanced oil recovery methods for heavy oil production(most especially,thermal fluid injection)usually result in the formation of water-in-oil(W/O)emulsion.In reality,the emulsion produced also contains some fine solid mineral particles such as silica,which,depending on its quantity,may alter the viscosity and/or rheological properties of the fluid.A series of binary-component emulsions were separately prepared by dispersing silica nanoparticles[phase fraction,βs,=0.5%–5.75%(wt/v)]in heavy oil(S/O suspension)and by dispersing water[water cut,θw=10%–53%(v/v)]in heavy oil(W/O emulsion).Ternary-component emulsions comprising heavy oil,water droplets and suspended silica nanoparticles(S/W/O)were also prepared with similar ranges ofθw andβs.The viscosity was measured at different shear rates(5.1–1021.4 s-1)and temperatures(30–70°C).Both binary-component and ternary-component emulsion systems were observed to exhibit nonNewtonian shear thinning behaviour.The viscosity of the heavy oil and W/O emulsions increased in the presence of silica nanoparticles.The effect was,however,less signifi cant belowβs=2%(wt/v).Moreover,a generalized correlation has been proposed to predict the viscosity of both binary-component and ternary-component emulsions.
文摘Interfacial properties rhamnolipids from an extract produced by a strain of Pseudomonas aeruginosa were analyzed in this study. The extract of rhamnolipid was characterized by surface tension in different conditions;interfacial tension with different hydrocarbons;critical micelle concentration under different pH and temperatures;particle size and emulsification capacity using laser light profiling. It was observed that the rhamnolipids extract are sensitive to variations in pH, thermostable and function as good emulsificant for emulsification of methyl methacrylate. The emulsion stability order in function of the oil phase was methyl methacrylate > emulsions of castor oil > emulsion n-heptane > emulsion toluene > emulsion hexadecane > octane emulsion. The data presented show that rhamnolipid extracts may be used to formulate stable emulsions of methyl methacrylate. This process can be used to do nano/microsphere of polymethyl methacrylate.
基金funded by the National Natural Science Foundation of China(Grant Nos.31270625 and 21406122)
文摘Alkenyl succinic anhydride(ASA) is a popular paper-sizing agent that is generally added to papermaking systems as an aqueous emulsion. Herein, we reviewed the recent work focusing on ASA emulsions stabilized by solid particles. Solid particle-stabilized ASA emulsions generally possess high ASA content and exhibit good sizing performance. The particles that have been used to stabilize ASA emulsions typically include montmorillonite, laponite, alumina, TiO_2, Fe_3O_4, polyaluminum sulfate(PAS), and cellulose nanocrystals(CNCs). Montmorillonite is the first extensively studied particle stabilizer for ASA emulsions. Laponite is undoubtedly the most competent particle stabilizer for preparing ASA emulsions with high sizing efficiency. Montmorillonite and laponite can be used individually as stabilizers after modification or as co-stabilizers with other particles or polymers. TiO_2, alumina, PAS, and CNCs are commonly used as stabilizers either individually or with other particles.
文摘Enhancement of oxidative stability of canola oil extracted from seed subjected to prior heat-treatment has been attributed to heat-induced generation of antioxidants from phenolic precursors occurring in canola seed. Dispersion of aqueous extracts of intact seed oil bodies (OBs) in water is a novel and interesting way of producing natural and oxidatively stable food emulsions with minimal use of synthetic antioxidants and emulsifiers. As there is growing interest in natural food emulsions containing unsaturated oils, we investigated whether the oxidative stability of canola OB emulsions could be further improved by subjecting canola seed to heat-treatment prior to oil body extraction. Oil-in-water (5%, w/w) emulsions of OBs extracted from canola seed before and after heat-treatment were considerably more resistant to oxidation than emulsions prepared from refined canola oil and Tween? 40 emulsifier. However, only small amounts (0.9% - 4.5% by weight) of the phenolic compounds present in canola seed were transferred to the OBs after aqueous extraction, and consequently there was no discernible effect on oxidative stability as a result of prior heat-treatment of the seed. Thus, in contrast to oil, there is no oxidative stability benefit to be gained by subjecting canola seed to heat-treatment prior to extraction of OBs.
文摘With the advent of new, particularly mixed-oil lipid emulsions approved by the United States Food & Drug Administration (FDA), clinicians have more options when choosing one as part of the parenteral nutrition support of patients. Lipid products long-standing availability in Europe and other parts of the world has certainly facilitated the process in the United States, where there was little evolution before 2014. These newer oil-based emulsions are finding their way to be used in pediatrics, as studies are being carried out that will result in pediatric labeling. Pediatric clinicians may find themselves wondering how these lipid emulsions are different from those that have come before;whether the same dosing or administration practices apply as with the traditional soybean-oil lipid emulsion, and if they can be used for other more emergent interventions. We present this review of the current lipid emulsions available in the U.S. market, highlighting the differences among them, as well as, providing some practical information for clinicians that can assist them in their day-to-day duties.
文摘In order to study the profile control characteristics of emulsions in porous medium, the heterogeneous experimental model was established, by which the experimental scheme was designed with different permeabilities, matching degree of particle size and concentration of emulsions. Based on experimental results of physical simulation, the concept of distributing rate and changing coefficient was introduced to quantitatively evaluate the profile control characteristics of emulsions. The results of the study show that, as the permeability ratio and emulsion concentration increase, the profile control characteristics of emulsions will enhance. The profile control characteristics of emulsions will be the best. The profile control scheme with emulsions was implemented in Bohai X oil field, The research results can be used for reference to design the profile control scheme in Bohai heterogeneous reservoir.
文摘Objective:The aim of this study was to discover the potential biomarkers changes on a rat model of isoproterenol (ISO) induced myocardial ischaemia before and after treatment with a Xiangdan submicron emulsion and to explore the unclearing mechanisms by urinary metabolomics.Methods:Three active traditional Chinese medicine (TCM) ingredients were formulated into a lyophilized submicron emulsion powder with hydroxypropyl-β-cyclodextrin encapsulation by high pressure homogenization technology.The three ingredients were given both separately and combined,and the corresponding effects of the three drugs were compared.Principal component analysis (PCA) and the HPLC-UV analytical method was applied to explore the change of composition of urine metabolites in a rat model of isoproterenol induced myocardial ischaemia.Results:Analytical methods measuring the three active ingredients in urine samples were established.PCA score plots revealed that the therapeutic effect of the Xiangdan submicron emulsion was more significant than that of the Xiangdan injection.There was a synergistic effect among the three active ingredients.Furthermore,studies of rat metabolism changes and structure analysis of biological markers indicated that the mechanism of Xiangdan formulations was related to the inhibition of abnormal tryptophan metabolism.Conclusion:Xiangdan preparations had a confirmed effect in the treatment of coronary heart disease,especially with the novel Xiangdan submicron emulsion formulation.Urinary metabolomics methods to monitor special biomarker changes is an excellent method to reveal the mechanism of action of TCM drugs.
文摘Cosmetic emulsions, as all macro emulsions, are inherently unstable systems, from a thermodynamic viewpoint. More specific eco-friendly oil/water (O/W) cosmetic emulsions are usually less stable than conventional ones as milder chemicals or less intense (energy consuming) production processes are involved. In this context, two traditional techniques an optical technique and a volumetric one have been used for the assessment of the stability of cosmetic emulsions and compared to each other. Eco-friendly cosmetic emulsions were produced with different olive oil/water extracts (Rosmarinus officinalis and Calendula officinalis extracts) and emulsifier (Glycerol monostearate, GMS) concentrations. Emulsions’ stability was registered simultaneously by 1) Microscopy photos of samples withdrawn at regular intervals from the test vessel;2) global volumetric measurements of the different phases (water/oil/emulsion) inside the test vessel made at regular intervals for determining the evolution of the location of the phases separation interface. Analysis of the results of each technique and comparisons among them are presented and discussed in detail.
文摘Multiple emulsions are of great therapeutic interest especially in the administration of medicines which can be inactivated by digestive enzymes;moreover the researches of formulation not being often easy, a control of the different phases physicochemical parameters would be of great interest in rapid formulations and at low cost. When formulating emulsions, the preliminary tests, also known as formulation tests, constitute a step which can be long and expensive because of the quantity of reagents that can be used. A rigorous methodology could thus be of great interest, which is at the aim of our study which consists of evaluating the physico-chemical parameters of different phases used to make thus multiple emulsions. In our study, physico-chemical parameters such as conductivity, pH, density, viscosity, and surface tension have been studied by direct measurement using equipment and also by means of suitable mounting. The results showed that the pH and the surface tension have an important role in the prediction of the stability of emulsions, these latter must be of the same order of magnitude. For all phases conductivity does not have too much interest apart from helping to determine the type of the emulsion.
