A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles...A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles were investigated.The whiteness,water-holding capacity,storage modulus(G')and texture properties of the MPGs were significantly improved by adding 1%-2%Pickering emulsion(P<0.05).Meanwhile,Raman spectral analysis demonstrated that Pickering emulsion promoted the transformation of secondary structure,enhanced hydrogen bonds and hydrophobic interactions,and promoted the transition of disulfide bond conformation from g-g-g to g-g-t and t-g-t.At an emulsion concentration of 2%,theα-helix content decreased by 10.37%,while theβ-sheet content increased by 7.94%,compared to the control.After F-T cycles,the structure of the MPGs was destroyed,with an increase in hardness and a decrease in whiteness and water-holding capacity,however,the quality degradation of MPGs was reduced with 1%-2%Pickering emulsion.These findings demonstrated that SSOS-Pickering emulsions,as potential fat substitutes,can enhance the gel properties and the F-T stability of MPGs.展开更多
The core drivers of the modern food industry are meeting consumer demand for tasty and healthy foods.The application of food flavor perception enhancement can help to achieve the goals of salt-and sugar-reduction,with...The core drivers of the modern food industry are meeting consumer demand for tasty and healthy foods.The application of food flavor perception enhancement can help to achieve the goals of salt-and sugar-reduction,without compromising the sensory quality of the original food,and this has attracted increasing research attention.The analysis of bibliometric results from 2002 to 2022 reveals that present flavor perception enhancement strategies(changing ingredient formulations,adding salt/sugar substitutes,emulsion delivery systems)are mainly carry out based on sweetness,saltiness and umami.Emulsion systems is becoming a novel research foci and development trends of international food flavor perception-enhancement research.The structured design of food emulsions,by using interface engineering technology,can effectively control,or enhance the release of flavor substances.Thus,this review systematically summarizes strategies,the application of emulsion systems and the mechanisms of action of food flavor perception-enhancement technologies,based on odor-taste cross-modal interaction(OTCMI),to provide insights into the further structural design and application of emulsion systems in this field.展开更多
Inadequate strength and stability of active crude oil emulsions stabilized by conventional surfactants always lead to a limited plugging rate of plugging agents.Thus,to address this issue,the synthesis of amphiphilic ...Inadequate strength and stability of active crude oil emulsions stabilized by conventional surfactants always lead to a limited plugging rate of plugging agents.Thus,to address this issue,the synthesis of amphiphilic Janus nanosheets was effectively carried out for enhancing the system performances and subsequently characterized.Based on the outcomes of orthogonal tests,an assessment was conducted on the nanosheet and surfactant formulations to optimize the enhancement of emulsion properties.The experimental demonstration of the complex system has revealed its remarkable emulsifying capability,ability to decrease interfacial tension and improve rheological behavior at high temperature(80℃)and high salinity(35,000 ppm)conditions.Involving probable mechanism of the system performance enhancement is elucidated by considering the synergistic effect between surfactants and nanosheets.Furthermore,variables including water-to-oil ratio,salinity,temperature and stirring intensity during operation,which affect the properties of prepared emulsions,were investigated in detail.The efficacy and stability of the complex system in obstructing medium and high permeability cores were demonstrated.Notably,the core with a high permeability of 913.58 mD exhibited a plugging rate of 98.55%.This study establishes the foundations of medium and high permeability reservoirs plugging with novel active crude oil plugging agents in severe environments.展开更多
During heavy oil recovery in the Bohai Oilfield,substantial emulsification of oil and water occurred,primarily forming water-in-oil emulsions.This phenomenon could alter fluid dynamics within the subsurface porous med...During heavy oil recovery in the Bohai Oilfield,substantial emulsification of oil and water occurred,primarily forming water-in-oil emulsions.This phenomenon could alter fluid dynamics within the subsurface porous media,potentially impacting well production performance.To elucidate the properties of water-in-oil emulsions and their associated liquid resistance effects,this study conducted a series of rheological tests,microscopic examinations,and injection experiments.The results show that the droplet size and distribution of water-in-oil emulsions were primarily influenced by shear rate and water content,which in turn modified emulsion viscosity.The stability of water-in-oil emulsions was reduced when they flowed through porous media.The increase in emulsion viscosity and the liquid resistance effect collectively enhanced the seepage resistance of water-in-oil emulsions flowing through porous media.Notably,when the emulsion droplet size exceeded the pore throat size,over 90%of the total seepage resistance was attributable to the liquid resistance effect.Conversely,when the majority of the emulsion droplets were smaller than the pore throat,the viscosity accounted for more than 60%of the seepage resistance.Water-in-oil emulsions flowed through cores with permeabilities ranging from 50 to 100 mD,exhibiting threshold pressure gradients between 35 and 43 MPa/m.At a core permeability of 300 mD,the threshold pressure gradient was significantly reduced to 1 MPa/m.The presence of a waterin-oil emulsion in the reservoir could result in a production pressure differential falling below the threshold pressure,thereby reducing reservoir productivity.展开更多
CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility reduction.However,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fractio...CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility reduction.However,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely researched.In this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil recovery.Firstly,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT cell.Subsequently,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary tube.Furthermore,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were analyzed.The results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) emulsion.An inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was confirmed.CO_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water cut.Eventually,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,respectively.This work may provide guidelines for EOR using CO_(2) emulsions with high water cut.展开更多
The functional fractions (acid, basic, amphoteric and neutral fractions) are isolated from the Liaohe Du-84 heavy crude oil and Shengli Gudao Kenxi heavy crude oil by ion-exchange chromatography, but the conventional...The functional fractions (acid, basic, amphoteric and neutral fractions) are isolated from the Liaohe Du-84 heavy crude oil and Shengli Gudao Kenxi heavy crude oil by ion-exchange chromatography, but the conventional fractions (saturates, aromatics, resins and asphaltenes) are also isolated from the heavy crude oil. These components have been characterized by spectroscopic methods (FT-IR), namely acid number, basic nitrogen number, ultimate analysis and molecular weight measurements using vapor pressure osmometry (VPO). The ion-exchange chromatography method based on separation by a functional group induces a little change on the nature of the crudes and reasonable mass balances can be easily obtained.展开更多
The influences of an anionic-nonionic composite surfactant and petroleum sulfonate, used in surfactant-polymer flooding in Shengli Gudong oilfield, East China, on the interfacial properties of Gudong crude model oil a...The influences of an anionic-nonionic composite surfactant and petroleum sulfonate, used in surfactant-polymer flooding in Shengli Gudong oilfield, East China, on the interfacial properties of Gudong crude model oil and synthetic formation water was studied by measuring interfacial tension, interfacial viscoelasticity and Zeta potential. The in？ uence of the surfactants on the stability of Gudong water-in-oil （W/O） and oil-in-water （O/W） emulsions was evaluated by separating water from the W/O emulsion and residual oil in the aqueous phase of the O/W emulsion respectively. The results showed that the two kinds of surfactants, namely anionic-nonionic composite surfactant and petroleum sulfonate, are both able to decrease the interfacial tension between the oil phase and the aqueous phase and increase the surface potential of the oil droplets dispersed in the O/W emulsion, which can enhance the stability of the W/O and O/W crude oil emulsions. Compared with petroleum sulfonate, the anionic-nonionic composite surfactant is more interfacially active and able to enhance the strength of the interfacial film between oil and water, hence enhance the stability of the W/O and O/W emulsions more effectively.展开更多
The influence of different types and concentrations of polymers on the stability of Gudao crude oil emulsion was investigated by measuring the volume of water separated from the emulsions and the interfacial shear vis...The influence of different types and concentrations of polymers on the stability of Gudao crude oil emulsion was investigated by measuring the volume of water separated from the emulsions and the interfacial shear viscosity of the oil/water interfacial film. Experimental results indicate that the simulated water-in-oil emulsion with 40 mg/L of partially hydrolyzed polyacrylamide （HPAM） 3530S could be easily broken by adding demulsifier C and was readily separated into two layers. However, HPAM AX-74H and hydrophobically associating water-soluble polymer （HAP） could stabilize the crude oil emulsion. With increasing concentration of AX-74H and HAP, crude oil emulsions became more stable. Water droplets were loosely packed in the water-in model oil emulsion containing HPAM 3530S, but water droplets were smaller and more closely packed in the emulsion containing AX-74H or HAP. The polymers could be adsorbed on the oil/water interface, thereby increasing the strength of the interracial film and enhancing the emulsion stability.展开更多
An oil-based drilling fluid should be stable and tolerant to high temperatures for use in deep drilling. An invert emulsion of water in oil is a good choice as an oil- based drilling fluid which is a mixture of a soli...An oil-based drilling fluid should be stable and tolerant to high temperatures for use in deep drilling. An invert emulsion of water in oil is a good choice as an oil- based drilling fluid which is a mixture of a solid phase and two immiscible liquid phases stabilized by a polymeric surfactant. In deep drilling, due to high temperatures, the polymeric surfactant degrades and a phase separation occurs. Here, octadecyltrimethoxysilane-modified silica nanoparticles were used to form a stable invert emulsion of water in oil for the drilling fluid model which resulted in a milky fluid with the formation of 60 gm water droplets. In addition, rheological study showed that using hydrophobic silica nanoparticles resulted in a stable water in oil invert emulsion with desired properties for a drilling fluid that can be modified by adjusting the nanoparticle nature and content. Aging experiments at 120 ℃ indicated that they also have good stability at high temperatures for challenging drilling operations.展开更多
A detailed study of the mechanisms of the emissions of pions and protons in the forward and backward hemispheres in 4.5 A GeV/c oxygen-emulsion interactions has been carried out. The correlations between the multiplic...A detailed study of the mechanisms of the emissions of pions and protons in the forward and backward hemispheres in 4.5 A GeV/c oxygen-emulsion interactions has been carried out. The correlations between the multiplicities of secondary charged particles in the backward and forward hemispheres are investigated.展开更多
This study aims to develop a paraffin-based phase change material(PCM) emulsion with a low extent of supercooling for thermal energy storage(TES) systems to improve the cooling efficiency.Hexadecane-water emulsions we...This study aims to develop a paraffin-based phase change material(PCM) emulsion with a low extent of supercooling for thermal energy storage(TES) systems to improve the cooling efficiency.Hexadecane-water emulsions were prepared and characterized. Multi-wall carbon nanotubes(MWCNTs) were dispersed in the emulsion as a nucleating agent to reduce the supercooling. The MWCNTs were chemically modified with carboxyl groups to improve the dispersion of the tubular particles in the organic liquid. Thermal analyses of the emulsions by differential scanning calorimeter(DSC) indicated that the extent of supercooling was significantly reduced. The concentration of the nucleating agent for an effective supercooling suppression as found to be very low, in agreement with previous findings, and there appeared to be a minimum concentration for the supercooling reduction.展开更多
The effects of water content, shear rate, temperature, and solid particle concentration on viscosity reduction （VR） caused by forming stable emulsions were investigated using Omani heavy crude oil. The viscosity of ...The effects of water content, shear rate, temperature, and solid particle concentration on viscosity reduction （VR） caused by forming stable emulsions were investigated using Omani heavy crude oil. The viscosity of the crude oil was initially measured with respect to shear rates at different temperatures from 20 to 70℃. The crude oil exhibited a shear thinning behavior at all the temperatures. The strongest shear thinning was observed at 20℃. A non-ionic water soluble surfactant （Triton X-100） was used to form and stabilize crude oil emulsions. The emulsification process has significantly reduced the crude oil viscosity. The degree of VR was found to increase with an increase in water content and reach its maximum value at 50 % water content. The phase inversion from oil- oil emulsion occurred at 30 in-water emulsion to water-in- % water content. The results indicated that the VR was inversely proportional to temperature and concentration of silica nanoparticles. For water-in-oil emulsions, VR increased with shear rate and eventually reached a plateau at a shear rate of around 350 s^-1. This was attributed to the thinning behavior of the continuous phase. The VR of oil-in-water emulsions remained almost constant as the shear rate increased due to the Newtonian behavior of water, the continuous phase.展开更多
A new kind of emulsion containing nano TiO_2 was developed through the dispersion experiment. A commercial emulsion and a prepared by our lab emulsion without nano particles were chosen as controls to test the tribolo...A new kind of emulsion containing nano TiO_2 was developed through the dispersion experiment. A commercial emulsion and a prepared by our lab emulsion without nano particles were chosen as controls to test the tribological and antibacterial properties of this new emulsion. The load carrying capacity, friction coefficient and average diameter of wear scars were tested by a four-ball machine and the comprehensive antifriction parameter ω was calculated. The wetting angle was also tested using a JC200C1 wetting angle tester. The micro surface and roughness of rolled strips were analyzed to investigate the tribological performance of the recommended new emulsion in strip production. It is shown that the new nano-emulsion possesses a higher load carrying capacity and wetting ability. Therefore the abrasive/plowing wear is reduced more efficiently with the addition of nano particles, and the micro surface is improved. The density of bacteria in the emulsions was tested after the cold rolling experiment. The emulsion breaking ratio and bacteria density were also tested in different time intervals after the cold rolling experiment. The final p H values and bacteria density of different layers of emulsions were measured and the sediment was analyzed by TEM to evaluate the antibacterial behavior of this new emulsion. It is shown that the density of microbial colonies which led to a corruption of emulsions was decreased about 90% and the effective antibacterial period was prolonged.展开更多
Formation and flow of emulsions in porous media are common in all enhanced oil recovery tech- niques. In most cases, oil-in-water （O/W） emulsions are formed in porous media due to oil-water interaction. Even now, de...Formation and flow of emulsions in porous media are common in all enhanced oil recovery tech- niques. In most cases, oil-in-water （O/W） emulsions are formed in porous media due to oil-water interaction. Even now, detailed flow mechanisms of emulsions through porous media are not well understood. In this study, variation of rate of flow of O/W emulsions with pressure drop was studied experimentally, and rheological pa- rameters were calculated. The pressure drop increases with an increase in oil concentration in the O/W emulsion due to high viscosity. The effective viscosity of the emulsion was calculated from the derived model and expressed as a function of shear rate while flowing through porous media. Flow of O/W emulsions of different concentrations was evaluated in sand packs of different sand sizes. Emulsions were characterized by analyzing their stability, rheological properties, and tem- perature effects on rheological properties.展开更多
Total disintegration events produced by 4.5 A GeV/c ^16O-AgBr interactions are analysed to investigate the characteristics of secondary charged particles produced in such collisions. The multiplicity distributions of ...Total disintegration events produced by 4.5 A GeV/c ^16O-AgBr interactions are analysed to investigate the characteristics of secondary charged particles produced in such collisions. The multiplicity distributions of grey, black, and relativistic charged particles can be well represented by Gaussian distribution. The average multiplicity of grey particles is found to increase with the mass of projectile increasing, while that of black particles is found to decrease with the mass of projectile increasing. This result is in good agreement with the prediction of fireball model. Finally, the linear dependence between grey and black particles is observed, but there is no distinct dependence between the production of relativistic charged particles and the target excitation.展开更多
Structure of emulsifiers or functionality and molecular weight determines its rheology, emulsification and stability of emulsion explosives. Rheology of typical emulsifiers was studied by automatic rheometer. Relation...Structure of emulsifiers or functionality and molecular weight determines its rheology, emulsification and stability of emulsion explosives. Rheology of typical emulsifiers was studied by automatic rheometer. Relations between rheology and structural properties of typical emulsifiers were analyzed. Experimental results show that viscosity of emulsifiers didn＇ t change with shear rate at room temperature and appeared properties of Newtonian fluid. Viscosity of different component emulsifiers declines with temperature in different modes. The change of strain doesn＇ t affect modu- lus of emulsifiers. Loss modulus increases linearly with the increase of frequency in oscillation and storage modulus does non-linearly. The higher the temperature is, the lower change amplitude of loss modulus with frequency will be. The emulsifiers with imide and amide functionality for emulsion explosives have better shear properties at high temperature and better shapingness and stability at room temperature than other emulsifiers with ester and Sorbin Monoleate （SMO） functionality.展开更多
Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their pertormances tor methanol synthesis from syngas have been investigated. The influences of preparation ...Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their pertormances tor methanol synthesis from syngas have been investigated. The influences of preparation methods of aluminum emulsions on physicochemical and catalytic properties of catalysts were studied by XRD, SEM, XPS,N2 adsorption-desorption techniques and methanol synthesis from syngas. The preparation methods of aluminum emulsions were found to influence the catalytic activity, CuO crystallite size, surface area and Cu0 surface area and reduction process. The results show that the catalyst CN using the aluminum source prepared by addition the ammonia into the aluminum nitrate （NP） exhibited the best catalytic performance for methanol synthesis from syngas.展开更多
In the study,the two-color pyrometer technique was used to measure the transient temperature field of emulsion explosives with different contents of TiH_(2)powders.The experimental results showed that the introduction...In the study,the two-color pyrometer technique was used to measure the transient temperature field of emulsion explosives with different contents of TiH_(2)powders.The experimental results showed that the introduction of TiH_(2)powders could significantly increase the explosion temperature and fireball duration of emulsion explosive.When emulsion explosives were ignited,the average explosion temperature of pure emulsion explosive continuously decreased while emulsion explosives added with TiH_(2)powders increased at first and then decreased.When the content of TiH_(2)powders was 6 mass%,the explosion average temperature reached its maximum value of 3095 K,increasing by 43.7%as compared with that of pure emulsion explosive.In addition,the results of air blast experiment and explosion heat test showed that the variation trends of shock wave parameters,explosion heat and theoretical explosion temperature of emulsion explosives with different contents of TiH_(2)powders were basically consistent with that of explosion temperature measured by the two-color pyrometer technique.In conclusion,the two-color pyrometer technique would be conducive to the formula design of emulsion explosive by understanding the explosion temperature characteristics.展开更多
Waxy crude oil emulsion has thixotropic properties at the temperature near gel point,which is a macromechanical characterization of the structure failure and recovery of waxy crude oil emulsion.In this paper,the thixo...Waxy crude oil emulsion has thixotropic properties at the temperature near gel point,which is a macromechanical characterization of the structure failure and recovery of waxy crude oil emulsion.In this paper,the thixotropic behaviors of waxy crude oil emulsion near gel point were studied using hysteresis loop formed by stress linear increase and decrease,as well as the structural recovery characteristics.The influence of the loading conditions and water content on the thixotropy of waxy crude oil emulsion were analyzed with hysteresis loop area.The concept of"structural recovery"was introduced to study the degree of structural recovery after different stewing,and influencing factors were taken into account.Results have shown that for waxy crude oil emulsion,the failure to fully restore of the structure after lysis is the cause of the formation of hysteresis loop,and the loading conditions will not affect the strength of thixotropy and the degree of structural recovery.Additionally,the dispersed phase droplets weaken the thixotropy and structure recovery characteristics of waxy crude oil emulsion,and the greater the water content,the weaker the thixotropy.The findings can help to better understand the safe and economic operation of waxy crude oil-water pipeline transportation.展开更多
In this study,hydrogen-storage glass microballoons were introduced into emulsion explosives to improve the detonation performance of the explosives.The effect of hydrogen-storage pressure on the detonation characteris...In this study,hydrogen-storage glass microballoons were introduced into emulsion explosives to improve the detonation performance of the explosives.The effect of hydrogen-storage pressure on the detonation characteristics of emulsion explosives was systematically investigated.Detonation velocity experiments shows that the change of sensitizing gas and the increase of hydrogen pressure have different effects on the detonation velocity.The experimental parameters of underwater explosion increase first and then decreases with the increase of hydrogen pressure.The decrease of these parameters indicates that the strength of glass microballoons is the limiting factor to improve the detonation performance of hydrogen-storage emulsion explosives.Compared with the traditional emulsion explosives,the maximum peak pressure of shock wave of hydrogen-storage emulsion explosives increases by 10.6%at 1.0 m and 10.2%at 1.2 m,the maximum values of shock impulse increase by 5.7%at 1.0 m and 19.4%at 1.2 m.The stored hydrogen has dual effects of sensitizers and energetic additives,which can improve the energy output of emulsion explosives.展开更多
基金supported by the National Natural Science Foundation of China(U20A2067,32272360)。
文摘A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles were investigated.The whiteness,water-holding capacity,storage modulus(G')and texture properties of the MPGs were significantly improved by adding 1%-2%Pickering emulsion(P<0.05).Meanwhile,Raman spectral analysis demonstrated that Pickering emulsion promoted the transformation of secondary structure,enhanced hydrogen bonds and hydrophobic interactions,and promoted the transition of disulfide bond conformation from g-g-g to g-g-t and t-g-t.At an emulsion concentration of 2%,theα-helix content decreased by 10.37%,while theβ-sheet content increased by 7.94%,compared to the control.After F-T cycles,the structure of the MPGs was destroyed,with an increase in hardness and a decrease in whiteness and water-holding capacity,however,the quality degradation of MPGs was reduced with 1%-2%Pickering emulsion.These findings demonstrated that SSOS-Pickering emulsions,as potential fat substitutes,can enhance the gel properties and the F-T stability of MPGs.
基金supported by the National Key R&D Program of China(2022YFD2101305).
文摘The core drivers of the modern food industry are meeting consumer demand for tasty and healthy foods.The application of food flavor perception enhancement can help to achieve the goals of salt-and sugar-reduction,without compromising the sensory quality of the original food,and this has attracted increasing research attention.The analysis of bibliometric results from 2002 to 2022 reveals that present flavor perception enhancement strategies(changing ingredient formulations,adding salt/sugar substitutes,emulsion delivery systems)are mainly carry out based on sweetness,saltiness and umami.Emulsion systems is becoming a novel research foci and development trends of international food flavor perception-enhancement research.The structured design of food emulsions,by using interface engineering technology,can effectively control,or enhance the release of flavor substances.Thus,this review systematically summarizes strategies,the application of emulsion systems and the mechanisms of action of food flavor perception-enhancement technologies,based on odor-taste cross-modal interaction(OTCMI),to provide insights into the further structural design and application of emulsion systems in this field.
基金financially supported by National Natural Science Foundation of China(52374053)Beijing Natural Science Foundation(2204092)Beijing Municipal Excellent Talent Training Funds Youth Advanced Individual Project(2018000020124G163)。
文摘Inadequate strength and stability of active crude oil emulsions stabilized by conventional surfactants always lead to a limited plugging rate of plugging agents.Thus,to address this issue,the synthesis of amphiphilic Janus nanosheets was effectively carried out for enhancing the system performances and subsequently characterized.Based on the outcomes of orthogonal tests,an assessment was conducted on the nanosheet and surfactant formulations to optimize the enhancement of emulsion properties.The experimental demonstration of the complex system has revealed its remarkable emulsifying capability,ability to decrease interfacial tension and improve rheological behavior at high temperature(80℃)and high salinity(35,000 ppm)conditions.Involving probable mechanism of the system performance enhancement is elucidated by considering the synergistic effect between surfactants and nanosheets.Furthermore,variables including water-to-oil ratio,salinity,temperature and stirring intensity during operation,which affect the properties of prepared emulsions,were investigated in detail.The efficacy and stability of the complex system in obstructing medium and high permeability cores were demonstrated.Notably,the core with a high permeability of 913.58 mD exhibited a plugging rate of 98.55%.This study establishes the foundations of medium and high permeability reservoirs plugging with novel active crude oil plugging agents in severe environments.
基金financially supported by the National Natural Science Foundation of China(No.ZX20230212)。
文摘During heavy oil recovery in the Bohai Oilfield,substantial emulsification of oil and water occurred,primarily forming water-in-oil emulsions.This phenomenon could alter fluid dynamics within the subsurface porous media,potentially impacting well production performance.To elucidate the properties of water-in-oil emulsions and their associated liquid resistance effects,this study conducted a series of rheological tests,microscopic examinations,and injection experiments.The results show that the droplet size and distribution of water-in-oil emulsions were primarily influenced by shear rate and water content,which in turn modified emulsion viscosity.The stability of water-in-oil emulsions was reduced when they flowed through porous media.The increase in emulsion viscosity and the liquid resistance effect collectively enhanced the seepage resistance of water-in-oil emulsions flowing through porous media.Notably,when the emulsion droplet size exceeded the pore throat size,over 90%of the total seepage resistance was attributable to the liquid resistance effect.Conversely,when the majority of the emulsion droplets were smaller than the pore throat,the viscosity accounted for more than 60%of the seepage resistance.Water-in-oil emulsions flowed through cores with permeabilities ranging from 50 to 100 mD,exhibiting threshold pressure gradients between 35 and 43 MPa/m.At a core permeability of 300 mD,the threshold pressure gradient was significantly reduced to 1 MPa/m.The presence of a waterin-oil emulsion in the reservoir could result in a production pressure differential falling below the threshold pressure,thereby reducing reservoir productivity.
基金The financial supports received from the National Natural Science Foundation of China(Nos.22178378,22127812)。
文摘CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility reduction.However,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely researched.In this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil recovery.Firstly,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT cell.Subsequently,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary tube.Furthermore,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were analyzed.The results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) emulsion.An inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was confirmed.CO_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water cut.Eventually,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,respectively.This work may provide guidelines for EOR using CO_(2) emulsions with high water cut.
文摘The functional fractions (acid, basic, amphoteric and neutral fractions) are isolated from the Liaohe Du-84 heavy crude oil and Shengli Gudao Kenxi heavy crude oil by ion-exchange chromatography, but the conventional fractions (saturates, aromatics, resins and asphaltenes) are also isolated from the heavy crude oil. These components have been characterized by spectroscopic methods (FT-IR), namely acid number, basic nitrogen number, ultimate analysis and molecular weight measurements using vapor pressure osmometry (VPO). The ion-exchange chromatography method based on separation by a functional group induces a little change on the nature of the crudes and reasonable mass balances can be easily obtained.
基金supported by the National Key Scientific and Technological Projects (2008ZX05011)
文摘The influences of an anionic-nonionic composite surfactant and petroleum sulfonate, used in surfactant-polymer flooding in Shengli Gudong oilfield, East China, on the interfacial properties of Gudong crude model oil and synthetic formation water was studied by measuring interfacial tension, interfacial viscoelasticity and Zeta potential. The in？ uence of the surfactants on the stability of Gudong water-in-oil （W/O） and oil-in-water （O/W） emulsions was evaluated by separating water from the W/O emulsion and residual oil in the aqueous phase of the O/W emulsion respectively. The results showed that the two kinds of surfactants, namely anionic-nonionic composite surfactant and petroleum sulfonate, are both able to decrease the interfacial tension between the oil phase and the aqueous phase and increase the surface potential of the oil droplets dispersed in the O/W emulsion, which can enhance the stability of the W/O and O/W crude oil emulsions. Compared with petroleum sulfonate, the anionic-nonionic composite surfactant is more interfacially active and able to enhance the strength of the interfacial film between oil and water, hence enhance the stability of the W/O and O/W emulsions more effectively.
文摘The influence of different types and concentrations of polymers on the stability of Gudao crude oil emulsion was investigated by measuring the volume of water separated from the emulsions and the interfacial shear viscosity of the oil/water interfacial film. Experimental results indicate that the simulated water-in-oil emulsion with 40 mg/L of partially hydrolyzed polyacrylamide （HPAM） 3530S could be easily broken by adding demulsifier C and was readily separated into two layers. However, HPAM AX-74H and hydrophobically associating water-soluble polymer （HAP） could stabilize the crude oil emulsion. With increasing concentration of AX-74H and HAP, crude oil emulsions became more stable. Water droplets were loosely packed in the water-in model oil emulsion containing HPAM 3530S, but water droplets were smaller and more closely packed in the emulsion containing AX-74H or HAP. The polymers could be adsorbed on the oil/water interface, thereby increasing the strength of the interracial film and enhancing the emulsion stability.
文摘An oil-based drilling fluid should be stable and tolerant to high temperatures for use in deep drilling. An invert emulsion of water in oil is a good choice as an oil- based drilling fluid which is a mixture of a solid phase and two immiscible liquid phases stabilized by a polymeric surfactant. In deep drilling, due to high temperatures, the polymeric surfactant degrades and a phase separation occurs. Here, octadecyltrimethoxysilane-modified silica nanoparticles were used to form a stable invert emulsion of water in oil for the drilling fluid model which resulted in a milky fluid with the formation of 60 gm water droplets. In addition, rheological study showed that using hydrophobic silica nanoparticles resulted in a stable water in oil invert emulsion with desired properties for a drilling fluid that can be modified by adjusting the nanoparticle nature and content. Aging experiments at 120 ℃ indicated that they also have good stability at high temperatures for challenging drilling operations.
基金Project supported by the National Natural Science Foundation of China （Grant No 10475054）, the Major Science and Technology Foundation of Ministry of Education of China （Grant No 205026）, the Natural Science Foundation of Shanxi Province, China（Grant No 20021007） and Shanxi Provincial Foundation for Returned Scholars of China（Grant No 20031046）.
文摘A detailed study of the mechanisms of the emissions of pions and protons in the forward and backward hemispheres in 4.5 A GeV/c oxygen-emulsion interactions has been carried out. The correlations between the multiplicities of secondary charged particles in the backward and forward hemispheres are investigated.
基金Supported by the Research Grant Council of the Hong Kong SAR government(GRF PolyU 5241/11E)
文摘This study aims to develop a paraffin-based phase change material(PCM) emulsion with a low extent of supercooling for thermal energy storage(TES) systems to improve the cooling efficiency.Hexadecane-water emulsions were prepared and characterized. Multi-wall carbon nanotubes(MWCNTs) were dispersed in the emulsion as a nucleating agent to reduce the supercooling. The MWCNTs were chemically modified with carboxyl groups to improve the dispersion of the tubular particles in the organic liquid. Thermal analyses of the emulsions by differential scanning calorimeter(DSC) indicated that the extent of supercooling was significantly reduced. The concentration of the nucleating agent for an effective supercooling suppression as found to be very low, in agreement with previous findings, and there appeared to be a minimum concentration for the supercooling reduction.
文摘The effects of water content, shear rate, temperature, and solid particle concentration on viscosity reduction （VR） caused by forming stable emulsions were investigated using Omani heavy crude oil. The viscosity of the crude oil was initially measured with respect to shear rates at different temperatures from 20 to 70℃. The crude oil exhibited a shear thinning behavior at all the temperatures. The strongest shear thinning was observed at 20℃. A non-ionic water soluble surfactant （Triton X-100） was used to form and stabilize crude oil emulsions. The emulsification process has significantly reduced the crude oil viscosity. The degree of VR was found to increase with an increase in water content and reach its maximum value at 50 % water content. The phase inversion from oil- oil emulsion occurred at 30 in-water emulsion to water-in- % water content. The results indicated that the VR was inversely proportional to temperature and concentration of silica nanoparticles. For water-in-oil emulsions, VR increased with shear rate and eventually reached a plateau at a shear rate of around 350 s^-1. This was attributed to the thinning behavior of the continuous phase. The VR of oil-in-water emulsions remained almost constant as the shear rate increased due to the Newtonian behavior of water, the continuous phase.
基金supported by the National Natural Science Foundation of China (contract/grant number: 51274037) affiliated to the project: "The research of lubrication model and interaction between nano-lubricating particles and rolling deformed surface."
文摘A new kind of emulsion containing nano TiO_2 was developed through the dispersion experiment. A commercial emulsion and a prepared by our lab emulsion without nano particles were chosen as controls to test the tribological and antibacterial properties of this new emulsion. The load carrying capacity, friction coefficient and average diameter of wear scars were tested by a four-ball machine and the comprehensive antifriction parameter ω was calculated. The wetting angle was also tested using a JC200C1 wetting angle tester. The micro surface and roughness of rolled strips were analyzed to investigate the tribological performance of the recommended new emulsion in strip production. It is shown that the new nano-emulsion possesses a higher load carrying capacity and wetting ability. Therefore the abrasive/plowing wear is reduced more efficiently with the addition of nano particles, and the micro surface is improved. The density of bacteria in the emulsions was tested after the cold rolling experiment. The emulsion breaking ratio and bacteria density were also tested in different time intervals after the cold rolling experiment. The final p H values and bacteria density of different layers of emulsions were measured and the sediment was analyzed by TEM to evaluate the antibacterial behavior of this new emulsion. It is shown that the density of microbial colonies which led to a corruption of emulsions was decreased about 90% and the effective antibacterial period was prolonged.
文摘Formation and flow of emulsions in porous media are common in all enhanced oil recovery tech- niques. In most cases, oil-in-water （O/W） emulsions are formed in porous media due to oil-water interaction. Even now, detailed flow mechanisms of emulsions through porous media are not well understood. In this study, variation of rate of flow of O/W emulsions with pressure drop was studied experimentally, and rheological pa- rameters were calculated. The pressure drop increases with an increase in oil concentration in the O/W emulsion due to high viscosity. The effective viscosity of the emulsion was calculated from the derived model and expressed as a function of shear rate while flowing through porous media. Flow of O/W emulsions of different concentrations was evaluated in sand packs of different sand sizes. Emulsions were characterized by analyzing their stability, rheological properties, and tem- perature effects on rheological properties.
基金Project supported by the National Natural Science Foundation of China （Grant No 10475054）, the Major Science and Technology Foundation of Ministry of Education of China （Grant No 205026）, the Natural Science Foundation of Shanxi Province, China （Grant No 20021007） and Shanxi Provincial Foundation for Returned Scholars, China （Grant No 20031046）.
文摘Total disintegration events produced by 4.5 A GeV/c ^16O-AgBr interactions are analysed to investigate the characteristics of secondary charged particles produced in such collisions. The multiplicity distributions of grey, black, and relativistic charged particles can be well represented by Gaussian distribution. The average multiplicity of grey particles is found to increase with the mass of projectile increasing, while that of black particles is found to decrease with the mass of projectile increasing. This result is in good agreement with the prediction of fireball model. Finally, the linear dependence between grey and black particles is observed, but there is no distinct dependence between the production of relativistic charged particles and the target excitation.
基金Supported by Independent Research Projects of State Key Laboratory of Explosion Science and Technology(ZDKT08-05)
文摘Structure of emulsifiers or functionality and molecular weight determines its rheology, emulsification and stability of emulsion explosives. Rheology of typical emulsifiers was studied by automatic rheometer. Relations between rheology and structural properties of typical emulsifiers were analyzed. Experimental results show that viscosity of emulsifiers didn＇ t change with shear rate at room temperature and appeared properties of Newtonian fluid. Viscosity of different component emulsifiers declines with temperature in different modes. The change of strain doesn＇ t affect modu- lus of emulsifiers. Loss modulus increases linearly with the increase of frequency in oscillation and storage modulus does non-linearly. The higher the temperature is, the lower change amplitude of loss modulus with frequency will be. The emulsifiers with imide and amide functionality for emulsion explosives have better shear properties at high temperature and better shapingness and stability at room temperature than other emulsifiers with ester and Sorbin Monoleate （SMO） functionality.
文摘Various Cu/ZnO/Al2O3 catalysts have been synthesized by different aluminum emulsions as aluminum sources and their pertormances tor methanol synthesis from syngas have been investigated. The influences of preparation methods of aluminum emulsions on physicochemical and catalytic properties of catalysts were studied by XRD, SEM, XPS,N2 adsorption-desorption techniques and methanol synthesis from syngas. The preparation methods of aluminum emulsions were found to influence the catalytic activity, CuO crystallite size, surface area and Cu0 surface area and reduction process. The results show that the catalyst CN using the aluminum source prepared by addition the ammonia into the aluminum nitrate （NP） exhibited the best catalytic performance for methanol synthesis from syngas.
基金supported by the National Natural Science Foundation of China(No.11972046)Outstanding Youth Project of Natural Science Foundation of Anhui Province(No.2108085Y02)+1 种基金Major Project of Anhui University Natural Science Foundation(No.KJ2020ZD30)Anhui University of Science and Technology Postgraduate Innovation Fund(No.2020CX2066)。
文摘In the study,the two-color pyrometer technique was used to measure the transient temperature field of emulsion explosives with different contents of TiH_(2)powders.The experimental results showed that the introduction of TiH_(2)powders could significantly increase the explosion temperature and fireball duration of emulsion explosive.When emulsion explosives were ignited,the average explosion temperature of pure emulsion explosive continuously decreased while emulsion explosives added with TiH_(2)powders increased at first and then decreased.When the content of TiH_(2)powders was 6 mass%,the explosion average temperature reached its maximum value of 3095 K,increasing by 43.7%as compared with that of pure emulsion explosive.In addition,the results of air blast experiment and explosion heat test showed that the variation trends of shock wave parameters,explosion heat and theoretical explosion temperature of emulsion explosives with different contents of TiH_(2)powders were basically consistent with that of explosion temperature measured by the two-color pyrometer technique.In conclusion,the two-color pyrometer technique would be conducive to the formula design of emulsion explosive by understanding the explosion temperature characteristics.
基金supported by the Natural Science Foundation of Heilongjiang Province(Grant No.LH2020E015)the General Project of Natural Science Research in Jiangsu Universities(Grant No.20KJB440004)+1 种基金the science and technology program of Changzhou University(Grant No.ZMF18020303 and ZMF18020304)the science and technology program of Jiangsu Key Laboratory of Oil and Gas Storage&Transportation Technology(Grant No.CDYQCY201903,CDYQCY201904 and CDYQCY202003)。
文摘Waxy crude oil emulsion has thixotropic properties at the temperature near gel point,which is a macromechanical characterization of the structure failure and recovery of waxy crude oil emulsion.In this paper,the thixotropic behaviors of waxy crude oil emulsion near gel point were studied using hysteresis loop formed by stress linear increase and decrease,as well as the structural recovery characteristics.The influence of the loading conditions and water content on the thixotropy of waxy crude oil emulsion were analyzed with hysteresis loop area.The concept of"structural recovery"was introduced to study the degree of structural recovery after different stewing,and influencing factors were taken into account.Results have shown that for waxy crude oil emulsion,the failure to fully restore of the structure after lysis is the cause of the formation of hysteresis loop,and the loading conditions will not affect the strength of thixotropy and the degree of structural recovery.Additionally,the dispersed phase droplets weaken the thixotropy and structure recovery characteristics of waxy crude oil emulsion,and the greater the water content,the weaker the thixotropy.The findings can help to better understand the safe and economic operation of waxy crude oil-water pipeline transportation.
基金financially supported by the National Natural Science Foundation of China under Project NO. 51874267 and NO. 51674229
文摘In this study,hydrogen-storage glass microballoons were introduced into emulsion explosives to improve the detonation performance of the explosives.The effect of hydrogen-storage pressure on the detonation characteristics of emulsion explosives was systematically investigated.Detonation velocity experiments shows that the change of sensitizing gas and the increase of hydrogen pressure have different effects on the detonation velocity.The experimental parameters of underwater explosion increase first and then decreases with the increase of hydrogen pressure.The decrease of these parameters indicates that the strength of glass microballoons is the limiting factor to improve the detonation performance of hydrogen-storage emulsion explosives.Compared with the traditional emulsion explosives,the maximum peak pressure of shock wave of hydrogen-storage emulsion explosives increases by 10.6%at 1.0 m and 10.2%at 1.2 m,the maximum values of shock impulse increase by 5.7%at 1.0 m and 19.4%at 1.2 m.The stored hydrogen has dual effects of sensitizers and energetic additives,which can improve the energy output of emulsion explosives.
