While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application...While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application of surfactants in different LIBs extinguishing agents,particularly in terms of patented technologies.The aim of this review paper is to provide an overview of the technological progress of LIBs and LIBs extinguishing agents in terms of patents in Korea,Japan,Europe,the United States,China,etc.The initial part of this review paper is sort out LIBs technology development in different regions.In addition,to compare LIBs extinguishing agent progress and challenges of liquid,solid,combination of multiple,and microencapsulated.The subsequent section of this review focuses on an in-depth analysis dedicated to the efficiency and challenges faced by the surfactants corresponding design principles of LIBs extinguishing agents,such as nonionic and anionic surfactants.A total of 451,760 LIBs-related patent and 20 LIBs-fire-extinguishing agent-related patent were included in the analyses.The extinguishing effect,cooling performance,and anti-recombustion on different agents have been highlighted.After a comprehensive comparison of these agents,this review suggests that temperature-sensitive hydrogel extinguishing agent is ideal for the effective control of LIBs fire.The progress and challenges of surfactants have been extensively examined,focusing on key factors such as surface activity,thermal stability,foaming properties,environmental friendliness,and electrical conductivity.Moreover,it is crucial to emphasize that the selection of a suitable surfactant must align with the extinguishing strategy of the extinguishing agent for optimal firefighting effectiveness.展开更多
Thermoelectrics are a promising solution to the recovery of some of the 60%of the worldwide energy wasted as heat.However,their conversion efficiency is low and the best performing materials are brittle,toxic,and made...Thermoelectrics are a promising solution to the recovery of some of the 60%of the worldwide energy wasted as heat.However,their conversion efficiency is low and the best performing materials are brittle,toxic,and made of expensive ceramics.The challenge in developing better performing materials is in disrupting the electrical vs thermal conductivity correlation,to achieve low thermal conductivity simultaneously with a high electrical conductivity.Carbon nanotubes allow for the decoupling of the electronic density of states from the phonon density of states and this paper shows that flexible,thin films of double-walled carbon nanotube(DWCNT)can form effective n-and p-doped semiconductors that can achieve a combined Seebeck coefficient of 157.6µV K^(−1),the highest reported for a single DWCNT device to date.This is achieved through selected surfactant doping,whose role is correlated with the length of the hydrocarbon chain of the hydrophobic tail group of the surfactant’s molecules.CNTs functionalized with Triton X-405 show the highest output power consisting of a single junction of p-and n-type thermoelectric elements,reaching as high as 67 nW for a 45 K temperature gradient.Thus enabling flexible,cheaper,and more efficient thermoelectric generators through the use of functionalized CNTs.展开更多
A simple, sensitive, and rapid analytical method is reported for the determination of surfactants. This is based on the use of an oppositely charged dye as the ion pair to form an ionic associate with the surfactant i...A simple, sensitive, and rapid analytical method is reported for the determination of surfactants. This is based on the use of an oppositely charged dye as the ion pair to form an ionic associate with the surfactant in a vessel, thus affording ion-associated adhesion on the inner wall of the vessel. After the adhesion, the remaining solution in the vessel is removed, and the ionic associate is dissolved in a suitable solvent. The absorbance of the resulting solution is measured spectrophotometrically to determine the concentration of the surfactant. Further, the mechanism of adhesion is elucidated.展开更多
Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion lumi...Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion luminescence intensities was reported for NaYF_(4)∶Yb/Er nanophosphors by a facile hydrothermal procedure with different surfactants.With the change of the surfactants from polyvinylpyrrolidone(PVP)to sodium citrate(CIT),edetate disodium(EDTA)or sodium dodecyl benzenesulfonate(SDBS),the morphology of NaYF_(4)∶Yb/Er nanophosphors transformed from nanoparticles with a diameter of about 70.0 nm to hexagonal nanoblocks with a thickness of about 125.0 nm and a length of about 240.0 nm,nanorods with a diameter of about 700.0 nm and a length of about 2.6μm,or nanowires with a diameter of 250.0 nm and a length of about 3.2μm.Simultaneously,their up-conversion luminescence intensity went down gradually under laser irradiation at a wavelength of 980 nm due to the increase of photobleaching.PVP-capped NaYF_(4)∶Yb/Er nanoparticles exhibited the smallest size and the strongest up-conversion luminescence intensity.Biological experiment results revealed that NaYF_(4)∶Yb/Er nanophosphors exhibited a high biocompatibility and could be used as biological labels with a perfect signal-to-noise ratio for cancer cell imaging.展开更多
Gemini quaternary ammonium salt surfactants, butane-a, co-bis（dimethyl dodeculammonium bromide） （BDDA） ethane-a, fl-bis（dimethyl dodeculammonium bromide） （EDDA） were adopted to comparatively study the flotatio...Gemini quaternary ammonium salt surfactants, butane-a, co-bis（dimethyl dodeculammonium bromide） （BDDA） ethane-a, fl-bis（dimethyl dodeculammonium bromide） （EDDA） were adopted to comparatively study the flotation behaviors of kaolinite, pyrophyllite and illite. It was found that three silicate minerals all exhibited good floatability with Gemini cationic surfactants as collectors over a wide pH range, while BDDA showed a stronger collecting power than EDDA. FTIR spectra and zeta potential analysis indicated that the mechanism of adsorption of Gemini collector molecules on three silicate minerals surfaces was almost identical for the electronic attraction and hydrogen bonds effect. The theoretically obtained results of density functional theory （DFT） at B3LYP/6-31G （d） level demonstrated the stronger collecting power of BDDA presented in the floatation test and zeta potential measurement.展开更多
Piroctone olamine(OCT) was used as the main bacteriostatic component, the inhibition of OCT in different kinds and mass concentrations of surfactants were studied. Six surfactants commonly used in personal care produc...Piroctone olamine(OCT) was used as the main bacteriostatic component, the inhibition of OCT in different kinds and mass concentrations of surfactants were studied. Six surfactants commonly used in personal care products, i.e. sodium laureth sulfate(AES), cocamidopropyl betaine(CAB 35), sodium lauroyl sarcosinate(LS-30), sodium lauroyl glutamate(ULS-30S), alkyl glycoside(APG), cocamide methyl MEA(CMMEA),were used. The results showed that the bacteriostatic of OCT decreased with the increase of AES, which was suggested ≤ 5%. OCT has good bacteriostatic performance in the systems of amino acid surfactants and high dosage of amphoteric surfactants, 5% LS 30 and ≥ 10% CAB 35 was recommended. High dosage of nonionic surfactant could interfere the bacteriostatic performance of OCT, the recommended dosage was ≤ 2%.In addition, OCT has good bacteriostatic performance against Staphylococcus aureus, Escherichia coli and Candida albicans when pH was controlled less than 5.5.展开更多
A series of heterogemini imidazolium surfactants with two-methylene spacer groups （[Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n） have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effect...A series of heterogemini imidazolium surfactants with two-methylene spacer groups （[Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n） have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effects of various reaction parameters, including stoichiometry, reaction temperature and time, were investigated. In addition, the surface activity study about heterogemini imidazolium surfactants was carried out and the influences of dissymmetric degree on the surface properties were also discussed.展开更多
Biological and synthetic surfactants were compared in terms of their ability to reduce interfacial tension, change the thermodynamic characteristics of a pre-conditioned surface, and to modify the rheological properti...Biological and synthetic surfactants were compared in terms of their ability to reduce interfacial tension, change the thermodynamic characteristics of a pre-conditioned surface, and to modify the rheological properties of their respective formulations at two different temperatures. Both classes of suffactants were able to reduce the inteffacial tension of their formulations to a similar level. However, the biosurfactants were more effective than the synthetics surfactants. Biosurfactants also altered the surface properties of stainless steel, rendering it hydrophilic. Microbial adhesion to stainless steel conditioned with biosurfactants was found to be thermodynamically unfavorable for all microbial strains tested. A linear relationship between shear stress and shear rate was obtained across a range of experimental conditions for all surfactant mixtures, indicating that all formulations behaved as Newtonian fluids.展开更多
Waste cooking oils and non-edible vegetable oils are abundant and renewable resources for bio-based materials which have showed great potential applications in many industries.In this study,five fatty acids commonly f...Waste cooking oils and non-edible vegetable oils are abundant and renewable resources for bio-based materials which have showed great potential applications in many industries.In this study,five fatty acids commonly found in non-edible vegetable oils,including palmitic acid,stearic acid,linoleic acid,linolenic acid,ricinoleic acid,and their mixtures,were used to produce bio-based zwitterionic surfactants through a facile and high-yield chemical modification.These surfactants demonstrated excellent surface/interfacial properties with the minimum surface tensions ranging from 28.4 mN/m to 32.8 mN/m in aqueous solutions.The interfacial tensions between crude oil and surfactant solutions were remarkably reduced to lower values ranging from 0.0028 mN/m to 0.1983 mN/m without the aid of extra alkali,which particularly implied a great potential application in enhanced oil recovery.Meanwhile,these bio-based surfactants also showed good wetting properties(contact angles of~51°comparing with that of double distilled water,92.04°)and appropriate predicted biodegradability(degradation order of“weeks”for bio-based surfactants synthesized from saturated fatty acids,and“months”for those synthesized from unsaturated fatty acids).Bio-based surfactants synthesized from unsaturated fatty acids showed better interfacial properties in reducing interfacial tension between crude oil and formation water.The bio-based surfactants presented in this study are alternative substitutes for traditional petroleum-based surfactants in various surfactant application fields.展开更多
The effect of reducing agents and surfactants on controlling the silver nanoplates was studied. Two reducing agents, trisodium citrate dehydrate (TSC) and potassium tartrate, were used to reduce the AgNO3 solution. In...The effect of reducing agents and surfactants on controlling the silver nanoplates was studied. Two reducing agents, trisodium citrate dehydrate (TSC) and potassium tartrate, were used to reduce the AgNO3 solution. In this redox system, polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS) and arabic gum were served as surfactants. The results showed that reducing agents and surfactants both act as the capping agent adhering to the certain facets of silver seeds to block this surface to grow. The relative intensity of reducing agents also takes an active part in influencing the growth rate and direction of silver seeds. It was also found that halides can accelerate the speed of Ostwald ripening by adding Cl?, Br? and I?into the aqueous and have some effects on the morphology of the nanoplates.展开更多
[Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were ...[Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were studied as well as their distribution in water and soil. Effects of rationing on desorption of PCBs were also analyzed. [Result]The potential of single surfactant to enhance the desorption of PCBs from soil in order was Tween 80 SDBS HTAB. Three surfactants were largely adsorbed on soil and the sorption followed HTABTween 80SDBS. The desorption of PCBs increased significantly and linearly with the increase of aqueous micelle concentration of surfactants. [Conclusion]Enhancing effect of three surfactants on PCBs desorption were obtained,which will provide theoretical basis for further analyzing.展开更多
Fine face-centered cubic (FCC) nickel powders were synthesized by liquid phase reduction with different surfactants. The products were investigated by scanning electron microscopy (SEM), laser particle size analyzer a...Fine face-centered cubic (FCC) nickel powders were synthesized by liquid phase reduction with different surfactants. The products were investigated by scanning electron microscopy (SEM), laser particle size analyzer and X-ray powder diffraction (XRD). The results indicate that the type, dosage and relative molecular mass of surfactants significantly impact the purity, dispersion property, particle size, size distribution and morphology of the products. The nonionic surfactants poly ethylene glycol (PEG) and polyethylene glycol sorbitan monostearate (Tween) showed better dispersing ability in the reaction system than the others. The optimal mass ratios of surfactant to Ni are 100 mg/g and 150 mg/g for PEG-600 and Tween-40, respectively. The products obtained in the optimal conditions have ideal morphology and narrow size distribution. Moreover, study on the relative molecular mass effect revealed that with the increase of the relative molecular mass of Tween, the morphology of nickel powders changed from sphere to spiny ball.展开更多
By using a downward penetration testing device, a large number of experiments were made to investigate the effects of surfactants (sodium succinate, sodium dodecyl sulfonate and dodecyl benzene sulfonic acid sodium sa...By using a downward penetration testing device, a large number of experiments were made to investigate the effects of surfactants (sodium succinate, sodium dodecyl sulfonate and dodecyl benzene sulfonic acid sodium salt) on the penetration ability of the calcium chloride and water glass solutions in four dust samples. The experimental results showed that the surfactants can enhance the penetration ability and decrease the surface tension of the calcium chloride and water glass solutions in great extent. After adding the surfactants in 0.2—0.6 wt.% to the solutions of calcium chloride and water glass in 5—25 wt.% respectively, the largest percent of penetration ability increases to 28% more. Among the three surfactants, the size of their effects on the penetration ability of calcium chloride and water solutions in the dust samples is dodecyl benzene sulfonic acid sodium salt, sodium dodecyl sulfonate and sodium succinate.The achieved conclusions are great significant for calcium chloride and water glass to be applied in the field of soil stabilization and raising dust control.展开更多
Hydraulic fracturing technology can significantly increase oil production from tight oil formations, but performance data show that production declines rapidly. In the long term, it is necessary to increase the develo...Hydraulic fracturing technology can significantly increase oil production from tight oil formations, but performance data show that production declines rapidly. In the long term, it is necessary to increase the development efficiency of block matrix, surfactant-aided imbibition is a potential way. The current work aimed to explain comprehensively how surfactants can enhance the imbibition rate. Laboratory experiments were performed to investigate the effects of wettability, interfacial tension(IFT), and relative permeability as the key parameters underlying surfactant solution imbibition. Two different types of surfactants, sodium dodecyl sulfate and polyethylene glycol octylphenol ether, at varied concentrations were tested on reservoir rocks. Experimental results showed that the oil recovery rate increased with increased wettability alteration and IFT and decreased residual oil saturation. A mechanistic simulator developed in previous studies was used to perform parametric analysis after successful laboratory-scale validation. Results were proven by parametric studies. This study,which examined the mechanism and factors influencing surfactant solution imbibition, can improve understanding of surfactant-aided imbibition and surfactant screening.展开更多
Naturally fractured carbonate reservoirs have very low oil recovery efficiency owing to their wettability and tightness of matrix.However,smart water can enhance oil recovery by changing the wettability of the carbona...Naturally fractured carbonate reservoirs have very low oil recovery efficiency owing to their wettability and tightness of matrix.However,smart water can enhance oil recovery by changing the wettability of the carbonate rock surface from oilwet to water-wet,and the addition of surfactants can also change surface wettability.In the present study,the effects of a solution of modified seawater with some surfactants,namely C12 TAB,SDS,and TritonX-100(TX-100),on the wettability of carbonate rock were investigated through contact angle measurements.Oil recovery was studied using spontaneous imbibition tests at 25,70,and 90°C,followed by thermal gravity analysis to measure the amount of adsorbed material on the carbonate surface.The results indicated that Ca2+,Mg2+,and SO42-.ions may alter the carbonate rock wettability from oil-wet to water-wet,with further water wettability obtained at higher concentrations of the ions in modified seawater.Removal of NaCl from the imbibing fluid resulted in a reduced contact angle and significantly enhanced oil recovery.Low oil recoveries were obtained with modified seawater at 25 and 70°C,but once the temperature was increased to 90°C,the oil recovery in the spontaneous imbibition experiment increased dramatically.Application of smart water with C12 TAB surfactant at 0.1 wt%changed the contact angle from 161°to 52°and enhanced oil recovery to 72%,while the presence of the anionic surfactant SDS at 0.1 wt%in the smart water increased oil recovery to 64.5%.The TGA analysis results indicated that the adsorbed materials on the carbonate surface were minimal for the solution containing seawater with C12 TAB at 0.1 wt%(SW+CTAB(0.1 wt%)).Based on the experimental results,a mechanism was proposed for wettability alteration of carbonate rocks using smart water with SDS and C12 TAB surfactants.展开更多
Surface modification by physical adsorption of a series of non-ionic surfactants including Tween 20, Tween 40, Tween 60, Tween 80 and Tween 85, was accomplished on polypropylene microporous hollow fiber and flat membr...Surface modification by physical adsorption of a series of non-ionic surfactants including Tween 20, Tween 40, Tween 60, Tween 80 and Tween 85, was accomplished on polypropylene microporous hollow fiber and flat membranes. The adsorption curve of the membrane surface was analyzed by weight measurements and the typical results showed a twoplatform character similarly. Differences in the degree and curve shape of adsorption resulting from such factors as concentration, temperature, as well as water cleaning time were observed for Tween 85 among other Tweens. Attenuated total reflection - Fourier transform infrared spectroscopy analysis and field emission scanning electron microscopy observation showed that the adsorption of Tween on polypropylene microporous membrane （PPMM） is effective and occurs mainly in the pores of PPMMs at low adsorption amount, and on the membrane surface also at high adsorption value.展开更多
The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammon...The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammonium bromide (CTAB) at molar fraction of AEO9, A EO9 α =0.5. The surface properties of the surfactants, critical micelle concentration (CMC), effectiveness of surface tension reduction (γCMC), maximum surface excess concentration (Γmax) and minimum area per molecule at the air/solution interface (Amin) were determined for both individual surfactants and their mixtures. The significant deviations from ideal behavior (attractive interactions) of the nonionic/ionic surfactant mixtures were determined. Mixtures of both AEO9/SDS and AEO9/CTAB exhibited synergism in surface tension reduction efficiency and mixed micelle formation, but neither exhibited synergism in surface tension reduction effectiveness.展开更多
Improving peroral delivery efficiency is always a persistent goal for both small-molecule and macromolecular drug development. However,intestinal mucus barrier which greatly impedes drug-loaded nanoparticles penetrati...Improving peroral delivery efficiency is always a persistent goal for both small-molecule and macromolecular drug development. However,intestinal mucus barrier which greatly impedes drug-loaded nanoparticles penetration is commonly overlooked. Therefore,in this study,taking fluorescent labeled PLGA(poly(lactic-co-glycolic acid)) nanoparticles as a tool,the influence of anionic and nonionic surfactants on mucus penetration ability of nanoparticles and their mucus barrier regulating ability were studied. The movement of PLGA nanoparticles in mucus was tracked by multiple particles tracking method(MPT).Alteration of mucus properties by addition of surfactants was evaluated by rheology and morphology study. Rat intestinal villus penetration study was used to further evaluate penetration enhancement of nanoparticles. The effective diffusivities of the nanoparticles in surfactants pretreated mucus were increased by 2–3 times and the mucus barrier regulating capacity was also surfactant type dependent. Sodium dodecyl sulfate(SDS) increased the complex viscosity and viscoelastic properties of mucus,but poloxamer presented a decreased trend. Tween 80 maintained the rheological property of the mucus. With the mucus barrier regulated by surfactants,the penetration of nanoparticles in intestinal villus was obviously increased. In summary,the mucus penetration ability of nanoparticles could be enhanced by altering mucus microenvironment with surfactants. Tween 80 which largely retains the original mucus rheology and morphology properties may be a promising candidate for facilitating nanoparticle penetration through the mucus barrier with good safety profile.展开更多
The basis of this study is to identify the versatility of N,N,N＇-trimethyl-N＇-tallow-1,3-diaminopropane（DTTM） surfactant in high saline environments. The surfactant was examined with sodium chloride, NaCl, to unde...The basis of this study is to identify the versatility of N,N,N＇-trimethyl-N＇-tallow-1,3-diaminopropane（DTTM） surfactant in high saline environments. The surfactant was examined with sodium chloride, NaCl, to understand how triggers such as salt, p H, temperature, and surfactant concentration influences the viscoelastic response of the surfactant solution. The DTTM surfactant and salt（NaCl） concentrations used in steady-state shear viscosity analysis range from 0.2 wt% to 2 wt%and 5 wt% to 25 wt%, respectively. Along with DTTM results, three similar chemical structures are investigated to understand how viscosity changes with alterations in tail and head group composition. It was found that DTTM surfactant has the capability of transitioning from a foam-bearing to viscoelastic state at low surfactant concentrations under moderate to high saline conditions. A longer tail length promotes viscoelasticity and shear-thinning behavior. Terminals consisting of hydroxides or ethoxylates have a lower viscosity than that of methyl terminals. A head group consisting of two nitrogen atoms has a higher viscosity than those containing one nitrogen atom. The rheological characterization of DTTM presented in this paper is part of a larger study in determining the capability of this surfactant to foam CO2 for improving mobility control in CO2 enhanced oil recovery in high saline oil formations.展开更多
The influences of surfactant type and concentration on the content and uniformity of SiC particles in Ni-SiC deposit were studied in this paper. The electrochemical behavior of preparing Ni-SiC composite coating was i...The influences of surfactant type and concentration on the content and uniformity of SiC particles in Ni-SiC deposit were studied in this paper. The electrochemical behavior of preparing Ni-SiC composite coating was investigated using the cyclic voltammetry method. Then the impact of surfactants on the deposition potential of Ni-SiC coating was analyzed. Electrochemical studies showed that the cathode overvoltage increases gradually with increasing SDS（Sodium dodecyl sulfate） concentration. The CV curve showed the shift towards a lower current at a given potential with increasing SDS concentration. Ni-SiC composite coatings were prepared by electrodeposition. The experimental results show that the dispersion of 40 nm SiC in Ni-SiC coating obtained in the electrolyte containing SDS is superior that containing CTAB（cetyltrimethyl ammonium bromide）. CTAB increases the content of 40 nm SiC particles in the Ni-SiC coating, but the uniformity of 40 nm SiC particles in Ni-SiC composite coating is poor. SiC particles are still agglomerated. Compared with the anionic surfactant SDS and the cationic surfactant CTAB, surfactant SDS makes the particles better dispersed. But the contribution of surfactant SDS for co-deposition amount of SiC particles is negligible. The cationic surfactant CTAB can effectively improve the suspension performance of SiC particles and promote the co-deposition of SiC particles and metallic nickel. But there is still some reunion of SiC.展开更多
基金supported by the National Key Research and Development Program of China (No.2017YFC0804700)the Opening Project of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology (No.KFJJ23-23M)。
文摘While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application of surfactants in different LIBs extinguishing agents,particularly in terms of patented technologies.The aim of this review paper is to provide an overview of the technological progress of LIBs and LIBs extinguishing agents in terms of patents in Korea,Japan,Europe,the United States,China,etc.The initial part of this review paper is sort out LIBs technology development in different regions.In addition,to compare LIBs extinguishing agent progress and challenges of liquid,solid,combination of multiple,and microencapsulated.The subsequent section of this review focuses on an in-depth analysis dedicated to the efficiency and challenges faced by the surfactants corresponding design principles of LIBs extinguishing agents,such as nonionic and anionic surfactants.A total of 451,760 LIBs-related patent and 20 LIBs-fire-extinguishing agent-related patent were included in the analyses.The extinguishing effect,cooling performance,and anti-recombustion on different agents have been highlighted.After a comprehensive comparison of these agents,this review suggests that temperature-sensitive hydrogel extinguishing agent is ideal for the effective control of LIBs fire.The progress and challenges of surfactants have been extensively examined,focusing on key factors such as surface activity,thermal stability,foaming properties,environmental friendliness,and electrical conductivity.Moreover,it is crucial to emphasize that the selection of a suitable surfactant must align with the extinguishing strategy of the extinguishing agent for optimal firefighting effectiveness.
文摘Thermoelectrics are a promising solution to the recovery of some of the 60%of the worldwide energy wasted as heat.However,their conversion efficiency is low and the best performing materials are brittle,toxic,and made of expensive ceramics.The challenge in developing better performing materials is in disrupting the electrical vs thermal conductivity correlation,to achieve low thermal conductivity simultaneously with a high electrical conductivity.Carbon nanotubes allow for the decoupling of the electronic density of states from the phonon density of states and this paper shows that flexible,thin films of double-walled carbon nanotube(DWCNT)can form effective n-and p-doped semiconductors that can achieve a combined Seebeck coefficient of 157.6µV K^(−1),the highest reported for a single DWCNT device to date.This is achieved through selected surfactant doping,whose role is correlated with the length of the hydrocarbon chain of the hydrophobic tail group of the surfactant’s molecules.CNTs functionalized with Triton X-405 show the highest output power consisting of a single junction of p-and n-type thermoelectric elements,reaching as high as 67 nW for a 45 K temperature gradient.Thus enabling flexible,cheaper,and more efficient thermoelectric generators through the use of functionalized CNTs.
文摘A simple, sensitive, and rapid analytical method is reported for the determination of surfactants. This is based on the use of an oppositely charged dye as the ion pair to form an ionic associate with the surfactant in a vessel, thus affording ion-associated adhesion on the inner wall of the vessel. After the adhesion, the remaining solution in the vessel is removed, and the ionic associate is dissolved in a suitable solvent. The absorbance of the resulting solution is measured spectrophotometrically to determine the concentration of the surfactant. Further, the mechanism of adhesion is elucidated.
基金Shanghai Academic Research Leader,China(No.20XD1420200)Shanghai Shuguang Program,China(No.18SG29)。
文摘Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion luminescence intensities was reported for NaYF_(4)∶Yb/Er nanophosphors by a facile hydrothermal procedure with different surfactants.With the change of the surfactants from polyvinylpyrrolidone(PVP)to sodium citrate(CIT),edetate disodium(EDTA)or sodium dodecyl benzenesulfonate(SDBS),the morphology of NaYF_(4)∶Yb/Er nanophosphors transformed from nanoparticles with a diameter of about 70.0 nm to hexagonal nanoblocks with a thickness of about 125.0 nm and a length of about 240.0 nm,nanorods with a diameter of about 700.0 nm and a length of about 2.6μm,or nanowires with a diameter of 250.0 nm and a length of about 3.2μm.Simultaneously,their up-conversion luminescence intensity went down gradually under laser irradiation at a wavelength of 980 nm due to the increase of photobleaching.PVP-capped NaYF_(4)∶Yb/Er nanoparticles exhibited the smallest size and the strongest up-conversion luminescence intensity.Biological experiment results revealed that NaYF_(4)∶Yb/Er nanophosphors exhibited a high biocompatibility and could be used as biological labels with a perfect signal-to-noise ratio for cancer cell imaging.
基金Project(2013AA064102)supported by the High-tech Research and Development Program of ChinaProject(51004114)supported by the National Natural Science Foundation of China+1 种基金Project(2007B52)supported by the Foundation for the Author of National Excellent Doctoral Dissertation of ChinaProject(NCEP-08-0568)supported by the Program for New Century Excellent Talents in Chinese University
文摘Gemini quaternary ammonium salt surfactants, butane-a, co-bis（dimethyl dodeculammonium bromide） （BDDA） ethane-a, fl-bis（dimethyl dodeculammonium bromide） （EDDA） were adopted to comparatively study the flotation behaviors of kaolinite, pyrophyllite and illite. It was found that three silicate minerals all exhibited good floatability with Gemini cationic surfactants as collectors over a wide pH range, while BDDA showed a stronger collecting power than EDDA. FTIR spectra and zeta potential analysis indicated that the mechanism of adsorption of Gemini collector molecules on three silicate minerals surfaces was almost identical for the electronic attraction and hydrogen bonds effect. The theoretically obtained results of density functional theory （DFT） at B3LYP/6-31G （d） level demonstrated the stronger collecting power of BDDA presented in the floatation test and zeta potential measurement.
文摘Piroctone olamine(OCT) was used as the main bacteriostatic component, the inhibition of OCT in different kinds and mass concentrations of surfactants were studied. Six surfactants commonly used in personal care products, i.e. sodium laureth sulfate(AES), cocamidopropyl betaine(CAB 35), sodium lauroyl sarcosinate(LS-30), sodium lauroyl glutamate(ULS-30S), alkyl glycoside(APG), cocamide methyl MEA(CMMEA),were used. The results showed that the bacteriostatic of OCT decreased with the increase of AES, which was suggested ≤ 5%. OCT has good bacteriostatic performance in the systems of amino acid surfactants and high dosage of amphoteric surfactants, 5% LS 30 and ≥ 10% CAB 35 was recommended. High dosage of nonionic surfactant could interfere the bacteriostatic performance of OCT, the recommended dosage was ≤ 2%.In addition, OCT has good bacteriostatic performance against Staphylococcus aureus, Escherichia coli and Candida albicans when pH was controlled less than 5.5.
文摘A series of heterogemini imidazolium surfactants with two-methylene spacer groups （[Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n） have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effects of various reaction parameters, including stoichiometry, reaction temperature and time, were investigated. In addition, the surface activity study about heterogemini imidazolium surfactants was carried out and the influences of dissymmetric degree on the surface properties were also discussed.
文摘Biological and synthetic surfactants were compared in terms of their ability to reduce interfacial tension, change the thermodynamic characteristics of a pre-conditioned surface, and to modify the rheological properties of their respective formulations at two different temperatures. Both classes of suffactants were able to reduce the inteffacial tension of their formulations to a similar level. However, the biosurfactants were more effective than the synthetics surfactants. Biosurfactants also altered the surface properties of stainless steel, rendering it hydrophilic. Microbial adhesion to stainless steel conditioned with biosurfactants was found to be thermodynamically unfavorable for all microbial strains tested. A linear relationship between shear stress and shear rate was obtained across a range of experimental conditions for all surfactant mixtures, indicating that all formulations behaved as Newtonian fluids.
基金supported by the National Key Research and Development Program of China(No.2017YFB0308900)National Natural Science Foundation of China(Grant No.51574125)+1 种基金the Fundamental Research Funds for the Central Universities of China(No.50321101917017)the Research Program of State Key Laboratory of Bioreactor Engineering.
文摘Waste cooking oils and non-edible vegetable oils are abundant and renewable resources for bio-based materials which have showed great potential applications in many industries.In this study,five fatty acids commonly found in non-edible vegetable oils,including palmitic acid,stearic acid,linoleic acid,linolenic acid,ricinoleic acid,and their mixtures,were used to produce bio-based zwitterionic surfactants through a facile and high-yield chemical modification.These surfactants demonstrated excellent surface/interfacial properties with the minimum surface tensions ranging from 28.4 mN/m to 32.8 mN/m in aqueous solutions.The interfacial tensions between crude oil and surfactant solutions were remarkably reduced to lower values ranging from 0.0028 mN/m to 0.1983 mN/m without the aid of extra alkali,which particularly implied a great potential application in enhanced oil recovery.Meanwhile,these bio-based surfactants also showed good wetting properties(contact angles of~51°comparing with that of double distilled water,92.04°)and appropriate predicted biodegradability(degradation order of“weeks”for bio-based surfactants synthesized from saturated fatty acids,and“months”for those synthesized from unsaturated fatty acids).Bio-based surfactants synthesized from unsaturated fatty acids showed better interfacial properties in reducing interfacial tension between crude oil and formation water.The bio-based surfactants presented in this study are alternative substitutes for traditional petroleum-based surfactants in various surfactant application fields.
基金Project(51373097)supported by The National Natural Science Foundation of China
文摘The effect of reducing agents and surfactants on controlling the silver nanoplates was studied. Two reducing agents, trisodium citrate dehydrate (TSC) and potassium tartrate, were used to reduce the AgNO3 solution. In this redox system, polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS) and arabic gum were served as surfactants. The results showed that reducing agents and surfactants both act as the capping agent adhering to the certain facets of silver seeds to block this surface to grow. The relative intensity of reducing agents also takes an active part in influencing the growth rate and direction of silver seeds. It was also found that halides can accelerate the speed of Ostwald ripening by adding Cl?, Br? and I?into the aqueous and have some effects on the morphology of the nanoplates.
基金Supported by the National Natural Science Fund (20947003)~~
文摘[Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were studied as well as their distribution in water and soil. Effects of rationing on desorption of PCBs were also analyzed. [Result]The potential of single surfactant to enhance the desorption of PCBs from soil in order was Tween 80 SDBS HTAB. Three surfactants were largely adsorbed on soil and the sorption followed HTABTween 80SDBS. The desorption of PCBs increased significantly and linearly with the increase of aqueous micelle concentration of surfactants. [Conclusion]Enhancing effect of three surfactants on PCBs desorption were obtained,which will provide theoretical basis for further analyzing.
基金Projects(51074096,51274130)supported by the National Natural Science Foundation of China
文摘Fine face-centered cubic (FCC) nickel powders were synthesized by liquid phase reduction with different surfactants. The products were investigated by scanning electron microscopy (SEM), laser particle size analyzer and X-ray powder diffraction (XRD). The results indicate that the type, dosage and relative molecular mass of surfactants significantly impact the purity, dispersion property, particle size, size distribution and morphology of the products. The nonionic surfactants poly ethylene glycol (PEG) and polyethylene glycol sorbitan monostearate (Tween) showed better dispersing ability in the reaction system than the others. The optimal mass ratios of surfactant to Ni are 100 mg/g and 150 mg/g for PEG-600 and Tween-40, respectively. The products obtained in the optimal conditions have ideal morphology and narrow size distribution. Moreover, study on the relative molecular mass effect revealed that with the increase of the relative molecular mass of Tween, the morphology of nickel powders changed from sphere to spiny ball.
文摘By using a downward penetration testing device, a large number of experiments were made to investigate the effects of surfactants (sodium succinate, sodium dodecyl sulfonate and dodecyl benzene sulfonic acid sodium salt) on the penetration ability of the calcium chloride and water glass solutions in four dust samples. The experimental results showed that the surfactants can enhance the penetration ability and decrease the surface tension of the calcium chloride and water glass solutions in great extent. After adding the surfactants in 0.2—0.6 wt.% to the solutions of calcium chloride and water glass in 5—25 wt.% respectively, the largest percent of penetration ability increases to 28% more. Among the three surfactants, the size of their effects on the penetration ability of calcium chloride and water solutions in the dust samples is dodecyl benzene sulfonic acid sodium salt, sodium dodecyl sulfonate and sodium succinate.The achieved conclusions are great significant for calcium chloride and water glass to be applied in the field of soil stabilization and raising dust control.
基金supported by the Natural Science Foundation of China (Grant No. 51574257)National 973 Project (No. 2015CB250900)
文摘Hydraulic fracturing technology can significantly increase oil production from tight oil formations, but performance data show that production declines rapidly. In the long term, it is necessary to increase the development efficiency of block matrix, surfactant-aided imbibition is a potential way. The current work aimed to explain comprehensively how surfactants can enhance the imbibition rate. Laboratory experiments were performed to investigate the effects of wettability, interfacial tension(IFT), and relative permeability as the key parameters underlying surfactant solution imbibition. Two different types of surfactants, sodium dodecyl sulfate and polyethylene glycol octylphenol ether, at varied concentrations were tested on reservoir rocks. Experimental results showed that the oil recovery rate increased with increased wettability alteration and IFT and decreased residual oil saturation. A mechanistic simulator developed in previous studies was used to perform parametric analysis after successful laboratory-scale validation. Results were proven by parametric studies. This study,which examined the mechanism and factors influencing surfactant solution imbibition, can improve understanding of surfactant-aided imbibition and surfactant screening.
文摘Naturally fractured carbonate reservoirs have very low oil recovery efficiency owing to their wettability and tightness of matrix.However,smart water can enhance oil recovery by changing the wettability of the carbonate rock surface from oilwet to water-wet,and the addition of surfactants can also change surface wettability.In the present study,the effects of a solution of modified seawater with some surfactants,namely C12 TAB,SDS,and TritonX-100(TX-100),on the wettability of carbonate rock were investigated through contact angle measurements.Oil recovery was studied using spontaneous imbibition tests at 25,70,and 90°C,followed by thermal gravity analysis to measure the amount of adsorbed material on the carbonate surface.The results indicated that Ca2+,Mg2+,and SO42-.ions may alter the carbonate rock wettability from oil-wet to water-wet,with further water wettability obtained at higher concentrations of the ions in modified seawater.Removal of NaCl from the imbibing fluid resulted in a reduced contact angle and significantly enhanced oil recovery.Low oil recoveries were obtained with modified seawater at 25 and 70°C,but once the temperature was increased to 90°C,the oil recovery in the spontaneous imbibition experiment increased dramatically.Application of smart water with C12 TAB surfactant at 0.1 wt%changed the contact angle from 161°to 52°and enhanced oil recovery to 72%,while the presence of the anionic surfactant SDS at 0.1 wt%in the smart water increased oil recovery to 64.5%.The TGA analysis results indicated that the adsorbed materials on the carbonate surface were minimal for the solution containing seawater with C12 TAB at 0.1 wt%(SW+CTAB(0.1 wt%)).Based on the experimental results,a mechanism was proposed for wettability alteration of carbonate rocks using smart water with SDS and C12 TAB surfactants.
基金This work was financially supported by the High-Tech Research and Development Program of China (No. 2002AA601230) the Science-Research Program of Jiaxing city, China (No. 2005AY3013).
文摘Surface modification by physical adsorption of a series of non-ionic surfactants including Tween 20, Tween 40, Tween 60, Tween 80 and Tween 85, was accomplished on polypropylene microporous hollow fiber and flat membranes. The adsorption curve of the membrane surface was analyzed by weight measurements and the typical results showed a twoplatform character similarly. Differences in the degree and curve shape of adsorption resulting from such factors as concentration, temperature, as well as water cleaning time were observed for Tween 85 among other Tweens. Attenuated total reflection - Fourier transform infrared spectroscopy analysis and field emission scanning electron microscopy observation showed that the adsorption of Tween on polypropylene microporous membrane （PPMM） is effective and occurs mainly in the pores of PPMMs at low adsorption amount, and on the membrane surface also at high adsorption value.
基金Project (No. 2004C31058) supported by the National NaturalScience Foundation of China
文摘The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammonium bromide (CTAB) at molar fraction of AEO9, A EO9 α =0.5. The surface properties of the surfactants, critical micelle concentration (CMC), effectiveness of surface tension reduction (γCMC), maximum surface excess concentration (Γmax) and minimum area per molecule at the air/solution interface (Amin) were determined for both individual surfactants and their mixtures. The significant deviations from ideal behavior (attractive interactions) of the nonionic/ionic surfactant mixtures were determined. Mixtures of both AEO9/SDS and AEO9/CTAB exhibited synergism in surface tension reduction efficiency and mixed micelle formation, but neither exhibited synergism in surface tension reduction effectiveness.
基金financially supported by the National Natural Science Foundation of China (Grant No. 31870987)
文摘Improving peroral delivery efficiency is always a persistent goal for both small-molecule and macromolecular drug development. However,intestinal mucus barrier which greatly impedes drug-loaded nanoparticles penetration is commonly overlooked. Therefore,in this study,taking fluorescent labeled PLGA(poly(lactic-co-glycolic acid)) nanoparticles as a tool,the influence of anionic and nonionic surfactants on mucus penetration ability of nanoparticles and their mucus barrier regulating ability were studied. The movement of PLGA nanoparticles in mucus was tracked by multiple particles tracking method(MPT).Alteration of mucus properties by addition of surfactants was evaluated by rheology and morphology study. Rat intestinal villus penetration study was used to further evaluate penetration enhancement of nanoparticles. The effective diffusivities of the nanoparticles in surfactants pretreated mucus were increased by 2–3 times and the mucus barrier regulating capacity was also surfactant type dependent. Sodium dodecyl sulfate(SDS) increased the complex viscosity and viscoelastic properties of mucus,but poloxamer presented a decreased trend. Tween 80 maintained the rheological property of the mucus. With the mucus barrier regulated by surfactants,the penetration of nanoparticles in intestinal villus was obviously increased. In summary,the mucus penetration ability of nanoparticles could be enhanced by altering mucus microenvironment with surfactants. Tween 80 which largely retains the original mucus rheology and morphology properties may be a promising candidate for facilitating nanoparticle penetration through the mucus barrier with good safety profile.
基金supported by the Abu Dhabi National Oil Company and the University of Texas at Austin
文摘The basis of this study is to identify the versatility of N,N,N＇-trimethyl-N＇-tallow-1,3-diaminopropane（DTTM） surfactant in high saline environments. The surfactant was examined with sodium chloride, NaCl, to understand how triggers such as salt, p H, temperature, and surfactant concentration influences the viscoelastic response of the surfactant solution. The DTTM surfactant and salt（NaCl） concentrations used in steady-state shear viscosity analysis range from 0.2 wt% to 2 wt%and 5 wt% to 25 wt%, respectively. Along with DTTM results, three similar chemical structures are investigated to understand how viscosity changes with alterations in tail and head group composition. It was found that DTTM surfactant has the capability of transitioning from a foam-bearing to viscoelastic state at low surfactant concentrations under moderate to high saline conditions. A longer tail length promotes viscoelasticity and shear-thinning behavior. Terminals consisting of hydroxides or ethoxylates have a lower viscosity than that of methyl terminals. A head group consisting of two nitrogen atoms has a higher viscosity than those containing one nitrogen atom. The rheological characterization of DTTM presented in this paper is part of a larger study in determining the capability of this surfactant to foam CO2 for improving mobility control in CO2 enhanced oil recovery in high saline oil formations.
基金the Program for Liaoning Excellent Talents in University(LJQ2015074)the Shenyang Science and Technology Plan(17-231-1-15)
文摘The influences of surfactant type and concentration on the content and uniformity of SiC particles in Ni-SiC deposit were studied in this paper. The electrochemical behavior of preparing Ni-SiC composite coating was investigated using the cyclic voltammetry method. Then the impact of surfactants on the deposition potential of Ni-SiC coating was analyzed. Electrochemical studies showed that the cathode overvoltage increases gradually with increasing SDS（Sodium dodecyl sulfate） concentration. The CV curve showed the shift towards a lower current at a given potential with increasing SDS concentration. Ni-SiC composite coatings were prepared by electrodeposition. The experimental results show that the dispersion of 40 nm SiC in Ni-SiC coating obtained in the electrolyte containing SDS is superior that containing CTAB（cetyltrimethyl ammonium bromide）. CTAB increases the content of 40 nm SiC particles in the Ni-SiC coating, but the uniformity of 40 nm SiC particles in Ni-SiC composite coating is poor. SiC particles are still agglomerated. Compared with the anionic surfactant SDS and the cationic surfactant CTAB, surfactant SDS makes the particles better dispersed. But the contribution of surfactant SDS for co-deposition amount of SiC particles is negligible. The cationic surfactant CTAB can effectively improve the suspension performance of SiC particles and promote the co-deposition of SiC particles and metallic nickel. But there is still some reunion of SiC.
