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Experimental investigation of triton X-100 solution on pulsating heat pipe thermal performance
, Article Journal of Thermophysics and Heat Transfer ; Volume 32, Issue 3 , 2018 , Pages 806-812 ; 08878722 (ISSN) ; Ghasempour, R ; Shafii, M. B ; Ahmadi, M. H ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc
2018
Abstract
Pulsating heat pipes are cooling devices that are partially filled with working fluid. Working fluid thermophysical properties affect the thermal performance of pulsating heat pipes. In this research, the effect of adding a Triton X-100 surfactant to pure water and using the mixture as a working fluid is investigated experimentally. The results indicate that adding surfactant leads to improvement in the thermal performance of the pulsating heat pipe. In particular, the maximum of the thermal resistance improvement is about 61%, which is attributed to 0.01% surfactant concentration. Higher heat transfer ability is attributed to lower surface tension and the contact angle of the mixture...
Experimental investigation of the effects of surfactant on the dynamics of formation process of liquid drops
, Article Journal of Industrial and Engineering Chemistry ; Volume 89 , 2020 , Pages 183-193 ; Salehi, M. S ; Firoozabadi, B ; Afshin, H ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2020
Abstract
In the present study, the formation of surfactant-laden viscous drops in ambient air is experimentally investigated using a high-speed digital camera. The mixtures of 90%, 92.5%, and 95% glycerol by weight in water containing various concentrations of sodium dodecyl sulfate are chosen as the drop phase fluid. The focus of this work is to investigate the effects of concentration of surfactant dissolved in solutions with different viscosities, on physical and geometrical parameters related to drop formation process, such as the drop elongation, minimum neck thickness, formation time, and the drop volume. The formation of satellite drops and the influence of surfactant concentration on their...
Experimental and Theoretical Investigation on Thermal Conductivity of Combined Nanofluids
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor)
Abstract
Application of nanotechnology in the field of heat transfer has increased recently. The need to increase heat transfer rate yet decrease the size of cooling equipment, brought about lots of attention to thermal properties of Nanofluids. Nanofluid is the suspension of nanometer-sized solid particles in base liquid. Research on convective heat transfer of nanofluids which is only two decades old, shows great potential in increasing heat transfer rate. Although there is a remarkable research on thermal conductivity of Nanofluids, negligible research was conducted on combined Nanofluids . Developed Theory for thermal conductivity of combined nanofluid can be used to modeling the thermal...
Experimental Study and Modeling of Thermodynamic Stability of the Oil and Water Emulsions in the Presence of Surfactants And Different Degrees of Temperature
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Cyrus (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
Always, understanding the properties of crude oil and related phenomena of that has been noticeable matter. Surface tension is one of the important fluid properties and the evaluation of that is essential in oil industry especially in enhanced oil recovery method (EOR) and transport of crude oil by using emulsions.
In this research, interfacial tension (IFT) was measured via pendant drop method. The effect of three parameters was investigated on IFT for creating of stable oil/water emulsion. These parameters were temperature, concentration of surfactants, and salinity. They were varied between 25-65 ᵒC, 0.05-0.2 gr and 5000ppm respectively. It was used two types of surfactant; acid...
In this research, interfacial tension (IFT) was measured via pendant drop method. The effect of three parameters was investigated on IFT for creating of stable oil/water emulsion. These parameters were temperature, concentration of surfactants, and salinity. They were varied between 25-65 ᵒC, 0.05-0.2 gr and 5000ppm respectively. It was used two types of surfactant; acid...
Nanoparticles and Surfactants Complex Effects on Water Evaporation
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor) ; Jvadi, Aliyar (Supervisor)
Abstract
Interest in the study of evaporation of liquid droplets is associated with a variety of practical applications, ranging from fuel burning and intensification of heat and mass transfer processes to formation of nanostructures. The study of the evaporation of liquid droplets is a fundamental problem, and it is the subject of a large number of works. However, in droplet evaporation processes, there are still many fundamental issues requiring more in-depth studies. In this study, the effect of the presence of hydrophilic silica nanoparticles and cationic (CTAB), anionic (SDS) and nonionic (TX-100) surfactants separately and in combination on the evaporation rate of water in a pendant droplet...
Investigating Asphaltene Biodegradability by Microorganism Considering Oil-Water Interface
, M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahab (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
Asphaltine particle precipitation may lead to serious problems in petroleum industry; including wellbore transmissibility reduction. One of the proposed remedial methods is to make a use of the microorganisms which are able to consume the heavy hydrocarbon chains.
Hydrophobicity of a cell surface is one of the parameters which greatly affect the microorganism adhesion to water insoluble hydrocarbons, in which results a higher hydrocarbon biodegradation. Consequently as the hydrophobicity of a cell surface increases; the microorganism tendency to bond with the hydrocarbon molecule enhances. The presence of a surface active agent, as an instance a chemical surfactant, will affect the...
Hydrophobicity of a cell surface is one of the parameters which greatly affect the microorganism adhesion to water insoluble hydrocarbons, in which results a higher hydrocarbon biodegradation. Consequently as the hydrophobicity of a cell surface increases; the microorganism tendency to bond with the hydrocarbon molecule enhances. The presence of a surface active agent, as an instance a chemical surfactant, will affect the...
Analysis of the Surfactant Effect on Detachment of a Droplet in Immiscible Fluid Phase
, M.Sc. Thesis Sharif University of Technology ; Roostaazad, Reza (Supervisor)
Abstract
The phenomenon of oil drop detachment from solid surface has great importance in many different industries, such as coating, print, membrane emulsification, detergency, and oil enhancement recovery. In our study, we tried to explore this phenomenon. Therefore, we attempted to employ Young equation as force balance for the discussed system which is comprised of n-Decane as oil droplet, aqueous solution (brine) with SDS (Sodium Dodecyl Sulfate), and glass. Also, in order to find governing factors regarding oil detachment process -such as interfacial tension, contact angle, and line friction coefficient- we used an advanced apparatus equipped with horizontal microscope and digital video camera....
Compositional Modeling of Surfactant Adsorption in Chemical Flooding with Verification with Laboratory Data
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeed (Supervisor) ; Ghazanfari, Mohammad Hossein (Supervisor)
Abstract
One of the most important EOR methods in oil reservoirs is surfactant and polymer flooding. Surfactants cause decreasing in interfacial tension between oleic and aqueous phases. However, polymers give us efficient mobility control in displacing oil by increasing the viscosity of aqueous phase. Therefore, oil is displaced in aqueous phase by viscous forces.
One of the most important challenges in surfactant flooding is adsorption. The net surface charge distributed on the rock surface depends strongly on pH. When we inject surfactant in reservoir, electrostatic charge on rock surface causes the first-layer adsorption. After that we have had second-layer adsorption.
In this thesis we...
One of the most important challenges in surfactant flooding is adsorption. The net surface charge distributed on the rock surface depends strongly on pH. When we inject surfactant in reservoir, electrostatic charge on rock surface causes the first-layer adsorption. After that we have had second-layer adsorption.
In this thesis we...
Experimental investigation of rheological and morphological properties of water in crude oil emulsions stabilized by a lipophilic surfactant
, Article Journal of Dispersion Science and Technology ; Volume 34, Issue 3 , Feb , 2013 , Pages 356-368 ; 01932691 (ISSN) ; Ramazani, S. A. A ; Taghikhani, V ; Ghotbi, C ; Sharif University of Technology
2013
Abstract
Rheological behavior of two crude oils and their surfactant-stabilized emulsions with initial droplet sizes ranging from 0.5 to 75 μm were investigated at various temperatures under steady and dynamic shear testing conditions. In order to evaluate the morphology and Stability of emulsions, microscopic analysis was carried out over three months and average diameter and size distribution of dispersed droplets were determined. The water content and surfactant concentration ranged from 10 to 60% vol/vol and 0.1 to 10% wt/vol, respectively. The results indicated that the rheological properties and the physical structure and stability of emulsions were significantly influenced by the water content...
Combined model of mass-transfer coefficients for clean and contaminated liquid-liquid systems
, Article Industrial and Engineering Chemistry Research ; Volume 50, Issue 8 , 2011 , Pages 4608-4617 ; 08885885 (ISSN) ; Dehkordi, A. M ; Darbandi, M ; Shahalami, M ; Saien, J ; Sharif University of Technology
Abstract
Mass-transfer rates to and from drops in liquid-liquid extraction processes are often reduced by the presence of contaminants. To design an industrial extractor, it is essential to consider this contamination effect in a quantitative manner. To achieve this goal, an experimental investigation was conducted on the mass transfer into single drops for n-butanol-succinic acid-water, as the recommended test system by the European Federation of Chemical Engineering (EFCE). The effects of anionic (sodium dodecyl sulfate, SDS), cationic (dodecyl trimethyl ammonium chloride, DTMAC), and nonionic (octylphenol decaethylene glycol ether, Triton X-100) surfactants on the hydrodynamic and mass-transfer...
Comparison and modification of models in production of biosurfactant for Paenibacillus alvei and Bacillus mycoides and its effect on MEOR efficiency
, Article Journal of Petroleum Science and Engineering ; Volume 128 , April , 2015 , Pages 177-183 ; 09204105 (ISSN) ; Roostaazad, R ; Soleimani, M ; Arabian, D ; Moazed, M. T ; Rahimpour, M. R ; Mazinani, S ; Sharif University of Technology
Elsevier
2015
Abstract
Biosurfactant production from two indigenous consortia has already been investigated in two previous studies. In this study, comparison and modification of those models for having as much biosurfactant as possible was conducted. After characterization of bacteria by biochemical tests and 16S ribotyping, a fully modification on the final models was presented. Response surface methodology has the ability to investigate the liability of the parameters and models by the help of Desirability mode and R2 coefficient in Design Expert software. Our models in the previous works follow the style of (y=f(A,B,. . .)) and two Desirability of 0.968 and 0.996 for Paenibacillus alvei ARN63 and Bacillus...
Surfactant-assisted synthesis and characterization of hydroxyapatite nanorods under hydrothermal conditions
, Article Materials Science- Poland ; Volume 27, Issue 4 , 2009 , Pages 961-971 ; 01371339 (ISSN) ; Solati Hashjin, M ; Sara Shafiei, S ; Goudarzi, A ; Salarian, R ; Nemati, A ; Sharif University of Technology
2009
Abstract
Hydroxyapatite (HAp) nanorods with uniform morphology and controllable size were successfully synthesized by precipitating Ca(NO3) 24H2O and (NH4)2HPO4 in the presence of cetyltrimethylammonium bromide (CTAB) and polyethylene glycol 400 (PEG 400) as cationic surfactant and non-ionic cosurfactant, respectively, under hydrothermal conditions. The effect of hydrothermal temperature on the composition, morphology and size of HAp particles was studied using X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR) and scanning electron microscopy (SEM). Results revealed that the morphology and size of HAp particles can be effectively controlled by the presence of CTAB and PEG...
Prediction of critical micelle concentration of some anionic surfactants using multiple regression techniques: A quantitative structure-activity relationship study
, Article Journal of Surfactants and Detergents ; Volume 3, Issue 1 , 2000 , Pages 47-52 ; 10973958 (ISSN) ; Konouz, E ; Sharif University of Technology
2000
Abstract
Computer-assisted methods were employed to develop a statistical relationship between molecular-based structural parameters and log critical micelle concentration (CMC) of some anionic surfactants. The CMC of 31 alkyl sulfates and alkanesulfonates were used for model generation. Among different models, two equations were selected as the best, and their specifications are given. The statistics of these models together with cross-validation results indicate the capability of both models to predict the CMC of anionic surfactants. Three descriptors of Wiener number, reciprocal of the dipole moment, and reciprocal of the Randic index appear in the models. Results indicate that topological...
A machine learning framework for predicting entrapment efficiency in niosomal particles
, Article International Journal of Pharmaceutics ; Volume 627 , 2022 ; 03785173 (ISSN) ; Aftab, A ; Ghaemmaghami, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Niosomes are vesicles formed mostly by nonionic surfactant and cholesterol incorporation as an excipient. The drug entrapment efficiency of niosomal vesicles is particularly important and depends on many parameters. Changing the effective parameters to have maximum entrapment efficiency in the laboratory is time-consuming and costly. In this study, a machine learning framework was proposed to address these problems. In order to find the most critical parameter affecting the entrapment efficiency and its optimal value in a specific experiment, data were first extracted from articles of the last decade using keywords of niosome and thin-film hydration method. Then, deep neural network (DNN),...
Mixed protein-surfactant adsorption layers formed in a sequential and simultaneous way at water-air and water-oil interfaces
, Article Soft Matter ; Volume 8, Issue 22 , 2012 , Pages 6057-6065 ; 1744683X (ISSN) ; Kotsmar, C ; Ferri, J. K ; Javadi, A ; Karbaschi, M ; Krägel, J ; Wüstneck, R ; Miller, R ; Sharif University of Technology
2012
Abstract
Mixed protein-surfactant adsorption layers can be built up in two different ways. The classical way is when all components adsorb simultaneously from a mixed solution. Alternatively, the components adsorb one after another, i.e. in a sequential way. In the present work, the formation of such surface layers has been studied with the random coil protein β-casein in the presence of added anionic surfactant SDS and compared for two different interfaces: the water-air (W-A) and water-hexane (W-H) interfaces. The used experimental technique is a drop profile analysis tensiometer PAT-1 specially equipped with a coaxial double capillary for drop volume exchange during the experiments. The results...
Experimental investigation of asp flooding in fractured heavy oil five-spot systems
, Article 74th European Association of Geoscientists and Engineers Conference and Exhibition 2012 Incorporating SPE EUROPEC 2012: Responsibly Securing Natural Resources, 4 June 2012 through 7 June 2012 ; 2012 , Pages 3924-3928 ; 9781629937908 (ISBN) ; Ghazanfari, M. H ; Masihi, M ; Rashtchian, D ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2012
Abstract
Although alkaline-surfactant-polymer flooding is proved to be efficient for oil recovery from heavy oil reservoirs, the displacements mechanism/efficiency of this process in fractured systems needs to more discussion, especially in five-spot patterns. In this work, several ASP flooding test were performed on fractured micromodels which were initially saturated with heavy oil at constant flow rate and different fracture geometrical characteristics conditions. The ASP solutions are constituted from 5 polymers i.e. four synthetic polymers include three hydrolyzed polyacrylamide with different molecular weight as well as a non-hydrolyzed polyacrylamide and a biopolymer, 2 surfactants i.e. a...
Rheology, stability and filtration characteristics of colloidal gas aphron fluids: role of surfactant and polymer type
, Article Journal of Natural Gas Science and Engineering ; Volume 26 , September , 2015 , Pages 895-906 ; 18755100 (ISSN) ; Arabloo, M ; Ghazanfari, M. H ; Sharif University of Technology
Elsevier
2015
Abstract
Colloidal Gas Aphron (CGA) are finding increasing application in fields of science and engineering because of their distinctive characteristic. As interest in the application of CGA based fluids grows and in order to select the best procedure for using them in successful petroleum engineering operations, there is a need to gain a better understanding of the factors that affect their properties and behavior. This article discusses the rheological characterization, stability analysis and filtration properties of CGA based fluids for three bio-polymers and two ionic surfactant. The stability and filtration analysis were investigated with the static drain rate technique and API filtration tests,...
Experimental study of the chemical stimulation of Iranian fractured carbonate reservoir rocks as an EOR potential, the impact on spontaneous imbibition and capillary pressure
, Article Scientia Iranica ; Volume 17, Issue 1 C , 2010 , Pages 37-45 ; 10263098 (ISSN) ; Bastani, D ; Badakhshan, A ; Sharif University of Technology
2010
Abstract
Beside their worldwide abundance, oil recovery from fractured carbonate reservoirs is commonly low. Such reservoirs are usually oil-wet, thus, waterflooding leads into early breakthrough and low recovery due to the high conductivity of the fracture network, negative capillary pressure of the matrix and, consequently, the poor spontaneous imbibitions of water from fractures into the matrix during the course of waterflooding. In such problematic reservoirs, changing the wettability of the matrix toward water-wetness can improve spontaneous imbibition by changing the sign and, thus, the direction of capillary forces, resulting in an improvement of waterflood efficiency and, consequently, oil...
Adsorption of proteins at the solution/air interface influenced by added nonionic surfactants at very low concentrations for both components. 3. dilational surface rheology
, Article Journal of Physical Chemistry B ; Volume 119, Issue 9 , January , 2015 , Pages 3768-3775 ; 15206106 (ISSN) ; Aksenenko, E. V ; Lylyk, S. V ; Lotfi, M ; Miller, R ; Sharif University of Technology
Abstract
The influence of the addition of the nonionic surfactants C12 DMPO, C14 DMPO, C10 OH, and C10 EO5 at concentrations between 10-5 and 10-1 mmol/L to solutions of β-casein (BCS) and β-lactoglobulin (BLG) at a fixed concentration of 10-5 mmol/L on the dilational surface rheology is studied. A maximum in the viscoelasticity modulus |E| occurs at very low surfactant concentrations (10-4 to 10-3 mmol/L) for mixtures of BCS with C12 DMPO and C14 DMPO and for mixtures of BLG with C10 EO5 , while for mixture of BCS with C10 EO5 the value of |E| only slightly increased. The |E| values...
Acidic heavy oil recovery using a new formulated surfactant accompanying alkali–polymer in high salinity brines
, Article Journal of Surfactants and Detergents ; Volume 20, Issue 3 , 2017 , Pages 725-733 ; 10973958 (ISSN) ; Jadaly, A ; Ayatollahi, S ; Masihi, M ; Sharif University of Technology
Abstract
The strength of a newly formulated surfactant with an alkali and polymer (AS/ASP) to improve an acidic heavy oil recovery was laboratory evaluated by various flooding experiments. The comparative role of the parameters like chemical nature, surface wettability, salinity, temperature and injection scheme were explored at high temperature and pressure on Berea sandstone rocks. According to the results the anionic surfactant is capable of providing proper oil displacement under high salinity conditions around 15 wt%. Continuous monitoring of differential pressure response and effluents’ state clearly represented the formation of an emulsified oil in high saline solutions with both alkali and...