Emulsion of waxy crude oil is one of the common states in the subsea pipeline. At low temperatures in offshore environment, waxy crude oils with water could form the crude oil emulsion gel of oil-in-water emulsion. Th...Emulsion of waxy crude oil is one of the common states in the subsea pipeline. At low temperatures in offshore environment, waxy crude oils with water could form the crude oil emulsion gel of oil-in-water emulsion. Thus, the waxy crude oil emulsion viscoelastic behavior for deep sea transportation and restarting pipeline safety is particularly important. By means of MASIII HAAKE rheometer which is produced by German company, waxy crude oil emulsion viscoelastic behavior is explored at different volumetric water contents and different shear stresses. By analyzing the rate of change of shear rate in the initial stage, the influence rules of viscoelastic properties were summarized, with the change of volumetric water content and the applied shear stress and based on the experimental results, the law of emulsion is explained from the micro level. It is proposed that brittle fracture exists between wax crystals, and flexible fracture was found in the interaction between water droplets and wax crystals.展开更多
Membrane-based separation is a promising technology to eliminate water impurities from the oil phase.However,it remains a great challenge to separate water from highly emulsified viscous oil owing to the high stabilit...Membrane-based separation is a promising technology to eliminate water impurities from the oil phase.However,it remains a great challenge to separate water from highly emulsified viscous oil owing to the high stability of the water droplets in oil.Herein we report a surface wettability engineering on an alumina ceramic membrane to achieve an efficient separation of a water-in-oil(W/O)emulsion.Silanes with different carbon chain lengths and fluorinated status were introduced to endow the alumina membrane with different surface wettabilities.While all the modified membranes exhibited excellent separation of the W/O without Span 80(surfactant),the one with amphiphobic wettability and lowest surface energy failed to separate the Span 80 stabilized W/O.The presence of Span 80 reduced the interfacial tension of water droplets,making them easier to deform and penetrate the modified membrane with the lowest surface energy.It reveals that engineering proper surface wettability is the key to separating the oil and water phases.Besides,the modified membranes maintained decent separation performance and stability under long-term run separation of the emulsified W/O.展开更多
Salidroside(SAL)is a phenolic substance with high solubility and low permeability,which make it easy to cause the efflux effect of P-glycoprotein and degradation of intestinal flora,resulting in lower bioavailability....Salidroside(SAL)is a phenolic substance with high solubility and low permeability,which make it easy to cause the efflux effect of P-glycoprotein and degradation of intestinal flora,resulting in lower bioavailability.The aim of this study was to develop and optimize a water-in-oil nanoemulsion of SAL(w/o SAL-N)to explore its suitability in oral drug delivery systems.In this work,SAL-N was successfully prepared by water titration method at K_(m)=1 to construct the pseudo-ternary phase diagrams.Physical characterization including the average viscosity,pH,refractive index,particle size,PDI,TEM,DSC,the content of SAL,and stability study were performed.It was evaluated for drug release in vitro and pharmacokinetic studies in vivo.The optimized nanoemulsion formulation consisted of Labrafil M 1944 CS(63%),Span-80/Tween-80/EtOH(27%)and 200 mg·mL^(-1) SAL solution(SAL-SOL)(10%).Low viscosity and suitable pH were expected for the nanoemulsion.The spherical morphology and nanoscale size of SAL-N enhanced the stability of the nanoemulsion system.In vitro drug release showed that SAL-N had a better controlled release property than SAL-SOL at earlier time points.The pharmacokinetic studies exhibited that SAL-N had significantly higher in t_(1/2)(2.11-fold),AUC_(0-48 h)(1.75-fold)and MRT0-48 h(2.63-fold)than SAL-SOL(P<0.01).The w/o SAL-N prepared in this work can be effectively delivered via the oral route.It can be seen w/o nanoemulsion is a strategy for the drug with polyphenols to delay the release,enhance oral absorption and reduce metabolic rate.展开更多
Due to the important role of oil source in our life,the separation of water-in-oil emulsion is urgent and necessary.Membrane seperation technology has been an efficient and widely used method in separating oil-water s...Due to the important role of oil source in our life,the separation of water-in-oil emulsion is urgent and necessary.Membrane seperation technology has been an efficient and widely used method in separating oil-water separation.Herein,we report a versatile approach to fabricate surface carbonized membranes with self-standing property from biomass-derived precursor by synergistic charring of phytic acid,arginine and filter paper.The obtained membrane exhibited superhydrophobicity in oil,excellent fouling resistance,and self-supporting ability.The membrane can be cycle-used at least 12 times with high permeation flux(up to 1380 L·m^(-2)·h^(-1))and separation efficiency(up to 99.4%).展开更多
Mesoporous TiO2 microspheres with flower-like morphology, high specific surface area, and high- crystallinity primary crystalline-phase of anatase have been prepared through a water-in-oil emulsion synthesis route ass...Mesoporous TiO2 microspheres with flower-like morphology, high specific surface area, and high- crystallinity primary crystalline-phase of anatase have been prepared through a water-in-oil emulsion synthesis route assisted by solvothermal treatment. The as-prepared powder microspheres, as well as their precursor, were characterized by various techniques. Thermogravimetry and differential thermal analysis indicated that the optimal sintering temperature of the TiO2 precursor was 550 ℃. Field emission scanning electron microscopy, laser particle size analysis, and X-ray diffractionjointly confirmed that the precursor powder with a spherical structure and main particle sizes ranging from 3 to 20 μm had the same primary crystalline-phase as the TiO2 microspheres obtained from the calcination of the precur- sor at 550 ℃ for 4 h. The specific surface area of the TiO2 microspheres was approximately 123.6 m2/g according to the Brunauer-Emmett-Teller （BET） nitrogen adsorption results. Compared with the com- mercial TiO2 powder （P25）, the resulting TiO2 microspheres exhibited a higher photocatalytic activity. Based on the experimental results, a rational mechanism was proposed to elucidate the formation of the TiO2 microsoheres.展开更多
Hollow calcium silicate microparticles were prepared by mixing a water-in-oil (W/O) emulsion containing silicate ions in aqueous phase with an oil phase containing a calcium/di-2-ethylhexyl phosphoric acid (D2EHPA) co...Hollow calcium silicate microparticles were prepared by mixing a water-in-oil (W/O) emulsion containing silicate ions in aqueous phase with an oil phase containing a calcium/di-2-ethylhexyl phosphoric acid (D2EHPA) complex. The inorganic precipitation reaction at the oil-water interface was accelerated by using a simple W/O emulsion. Hollow microparticles were obtained when the mole ratio of D2EHPA and calcium in the oil phase was nearly 2:1. The shell formation of the par-ticles depended on the acceleration of the precipitation reaction, which could be accomplished by controlling the concentrations of the calcium and silicate ions.展开更多
We have studied synthesis of luminophore-doped silica nanoparticles by method of water-in-oil microemulsion, in which the luminophore are tris(2,2′-bipyridyl)
文摘Emulsion of waxy crude oil is one of the common states in the subsea pipeline. At low temperatures in offshore environment, waxy crude oils with water could form the crude oil emulsion gel of oil-in-water emulsion. Thus, the waxy crude oil emulsion viscoelastic behavior for deep sea transportation and restarting pipeline safety is particularly important. By means of MASIII HAAKE rheometer which is produced by German company, waxy crude oil emulsion viscoelastic behavior is explored at different volumetric water contents and different shear stresses. By analyzing the rate of change of shear rate in the initial stage, the influence rules of viscoelastic properties were summarized, with the change of volumetric water content and the applied shear stress and based on the experimental results, the law of emulsion is explained from the micro level. It is proposed that brittle fracture exists between wax crystals, and flexible fracture was found in the interaction between water droplets and wax crystals.
基金supported by the Guangzhou Science and Technology Plan(No.202102020219)National Natural Science Foundation of China(No.51908565)High-level talent research startup project of Chongqing Technology and Business University(No.2356007)。
文摘Membrane-based separation is a promising technology to eliminate water impurities from the oil phase.However,it remains a great challenge to separate water from highly emulsified viscous oil owing to the high stability of the water droplets in oil.Herein we report a surface wettability engineering on an alumina ceramic membrane to achieve an efficient separation of a water-in-oil(W/O)emulsion.Silanes with different carbon chain lengths and fluorinated status were introduced to endow the alumina membrane with different surface wettabilities.While all the modified membranes exhibited excellent separation of the W/O without Span 80(surfactant),the one with amphiphobic wettability and lowest surface energy failed to separate the Span 80 stabilized W/O.The presence of Span 80 reduced the interfacial tension of water droplets,making them easier to deform and penetrate the modified membrane with the lowest surface energy.It reveals that engineering proper surface wettability is the key to separating the oil and water phases.Besides,the modified membranes maintained decent separation performance and stability under long-term run separation of the emulsified W/O.
基金supported by Tianjin City High School Science Technology Fund Planning Project(No.2017KJ134)。
文摘Salidroside(SAL)is a phenolic substance with high solubility and low permeability,which make it easy to cause the efflux effect of P-glycoprotein and degradation of intestinal flora,resulting in lower bioavailability.The aim of this study was to develop and optimize a water-in-oil nanoemulsion of SAL(w/o SAL-N)to explore its suitability in oral drug delivery systems.In this work,SAL-N was successfully prepared by water titration method at K_(m)=1 to construct the pseudo-ternary phase diagrams.Physical characterization including the average viscosity,pH,refractive index,particle size,PDI,TEM,DSC,the content of SAL,and stability study were performed.It was evaluated for drug release in vitro and pharmacokinetic studies in vivo.The optimized nanoemulsion formulation consisted of Labrafil M 1944 CS(63%),Span-80/Tween-80/EtOH(27%)and 200 mg·mL^(-1) SAL solution(SAL-SOL)(10%).Low viscosity and suitable pH were expected for the nanoemulsion.The spherical morphology and nanoscale size of SAL-N enhanced the stability of the nanoemulsion system.In vitro drug release showed that SAL-N had a better controlled release property than SAL-SOL at earlier time points.The pharmacokinetic studies exhibited that SAL-N had significantly higher in t_(1/2)(2.11-fold),AUC_(0-48 h)(1.75-fold)and MRT0-48 h(2.63-fold)than SAL-SOL(P<0.01).The w/o SAL-N prepared in this work can be effectively delivered via the oral route.It can be seen w/o nanoemulsion is a strategy for the drug with polyphenols to delay the release,enhance oral absorption and reduce metabolic rate.
基金financially supported by the National Natural Science Foundation of China(Nos.21875147 and 51991351)the Fundamental Research Funds for the Central Universities。
文摘Due to the important role of oil source in our life,the separation of water-in-oil emulsion is urgent and necessary.Membrane seperation technology has been an efficient and widely used method in separating oil-water separation.Herein,we report a versatile approach to fabricate surface carbonized membranes with self-standing property from biomass-derived precursor by synergistic charring of phytic acid,arginine and filter paper.The obtained membrane exhibited superhydrophobicity in oil,excellent fouling resistance,and self-supporting ability.The membrane can be cycle-used at least 12 times with high permeation flux(up to 1380 L·m^(-2)·h^(-1))and separation efficiency(up to 99.4%).
基金The authors gratefully acknowledge the financial support for this work from State Key Development Program for Basic Research of China （No. 2010CB635107）, The National Natural Science Foundation of China （Nos. 51004046, 51202064, 51302073）, The National Natural Science Foundation of Hubei Province of China （No. 2010CDB05806）, Wuhan Youth Chenguang Program of Sci- ence and Technology （No. 2013070104010016）, and Middle-aged and Young Program of Educational Commission of Hubei Province （No. Q20101409）.
文摘Mesoporous TiO2 microspheres with flower-like morphology, high specific surface area, and high- crystallinity primary crystalline-phase of anatase have been prepared through a water-in-oil emulsion synthesis route assisted by solvothermal treatment. The as-prepared powder microspheres, as well as their precursor, were characterized by various techniques. Thermogravimetry and differential thermal analysis indicated that the optimal sintering temperature of the TiO2 precursor was 550 ℃. Field emission scanning electron microscopy, laser particle size analysis, and X-ray diffractionjointly confirmed that the precursor powder with a spherical structure and main particle sizes ranging from 3 to 20 μm had the same primary crystalline-phase as the TiO2 microspheres obtained from the calcination of the precur- sor at 550 ℃ for 4 h. The specific surface area of the TiO2 microspheres was approximately 123.6 m2/g according to the Brunauer-Emmett-Teller （BET） nitrogen adsorption results. Compared with the com- mercial TiO2 powder （P25）, the resulting TiO2 microspheres exhibited a higher photocatalytic activity. Based on the experimental results, a rational mechanism was proposed to elucidate the formation of the TiO2 microsoheres.
基金financially supported by the National Natural Science Foundation of China(51773012)Fundamental Research Funds for the Central Universities(buctrc202135)China Scholarship Council Program(201906880031).
文摘Hollow calcium silicate microparticles were prepared by mixing a water-in-oil (W/O) emulsion containing silicate ions in aqueous phase with an oil phase containing a calcium/di-2-ethylhexyl phosphoric acid (D2EHPA) complex. The inorganic precipitation reaction at the oil-water interface was accelerated by using a simple W/O emulsion. Hollow microparticles were obtained when the mole ratio of D2EHPA and calcium in the oil phase was nearly 2:1. The shell formation of the par-ticles depended on the acceleration of the precipitation reaction, which could be accomplished by controlling the concentrations of the calcium and silicate ions.
文摘We have studied synthesis of luminophore-doped silica nanoparticles by method of water-in-oil microemulsion, in which the luminophore are tris(2,2′-bipyridyl)
