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surface-active-agents
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Core flooding tests to investigate the effects of IFT reduction and wettability alteration on oil recovery during MEOR process in an Iranian oil reservoir
, Article Applied Microbiology and Biotechnology ; Volume 97, Issue 13 , July , 2013 , Pages 5979-5991 ; 01757598 (ISSN) ; Sharifinik, M ; Niazi, A ; Hashemi, A ; Ayatollahi, S ; Sharif University of Technology
2013
Abstract
Microbial enhanced oil recovery (MEOR) refers to the process of using bacterial activities for more oil recovery from oil reservoirs mainly by interfacial tension reduction and wettability alteration mechanisms. Investigating the impact of these two mechanisms on enhanced oil recovery during MEOR process is the main objective of this work. Different analytical methods such as oil spreading and surface activity measurements were utilized to screen the biosurfactant-producing bacteria isolated from the brine of a specific oil reservoir located in the southwest of Iran. The isolates identified by 16S rDNA and biochemical analysis as Enterobacter cloacae (Persian Type Culture Collection (PTCC)...
Improvements in permeation and fouling resistance of PVC ultrafiltration membranes via addition of Tetronic-1107 and Triton X-100 as two non-ionic and hydrophilic surfactants
, Article Water Science and Technology ; Volume 74, Issue 6 , 2016 , Pages 1469-1483 ; 02731223 (ISSN) ; Seyedi, S. M ; Rabiei, H ; Alvandifar, N ; Sharif University of Technology
IWA Publishing
Abstract
Two non-ionic and hydrophilic surfactant additives, Tetronic-1107 and Triton X-100, were added to poly(vinyl chloride)/NMP polymeric solution to prepare ultrafiltration membranes via immersion precipitation. Surfactants at three different weight percentages up to 6 wt% were added, and the fabricated membranes were characterized and their performance for water treatment in the presence of bovine serum albumin (BSA) as a foulant was assessed. The scanning electron microscopy images indicated remarkable changes in morphology due to higher thermodynamic instability after surfactant addition. The membranes are more porous with more macro-voids in the sub-layer. Plus, the membranes become more...
Controlled growth of hollow polyaniline structures: From nanotubes to microspheres
, Article Polymer (United Kingdom) ; Volume 54, Issue 21 , 2013 , Pages 5586-5594 ; 00323861 (ISSN) ; Ghorbani, M ; Shojaei, A ; Sharif University of Technology
2013
Abstract
Homogeneous and fairly monosized microspherical structures of polyaniline has been synthesized using a simple soft template method with β-naphthalene sulfonic acid (β-NSA) as both the surfactant and dopant, and ammonium persulfate (APS) as the oxidant at 2-5 C. The morphology of PANI-NSA was successfully controlled from nanotubes to microsphere, by changing the synthesis conditions (i.e. pH, the concentration of surfactant and monomer, and temperature). Some mechanistic aspects of the formation of nanotubes and hollow spheres have been discussed precisely based on SEM, TEM, DLS, FTIR and UV-visible results. Moreover, synthesis was performed under acidic environment to obtain further...
Monitoring the role of polymer and surfactant concentrations on bubble size distribution in colloidal gas aphron based fluids
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 556 , 2018 , Pages 93-98 ; 09277757 (ISSN) ; Kazemzadeh, E ; Kamari, E ; Ghazanfari, M. H ; Soleymani, M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Colloidal gas aphron (CGA) based fluids have recently been introduced to develop depleted hydrocarbon reservoirs due to their ability in controlling fluid losses. Bubbles size of CGAs plays an important role in pore blockage ability as the controlling mechanism in fluid invasion reduction. However, fundamental understanding of how bubble size distribution is controlled by polymer and surfactant concentrations is not well discussed in the available literature. Almost all reported experiences on CGAs sizing were conducted on single bubble behavior, and little attention has been given to the variation of bubble size distribution (BSD) of CGAs at different levels of polymer/surfactant...
Synthesis and characterization of MoO3 nanostructures by solution combustion method employing morphology and size control
, Article Journal of Nanoparticle Research ; Volume 12, Issue 4 , 2010 , Pages 1509-1521 ; 13880764 (ISSN) ; Kazemeini, M ; Rashidi, A. M ; Jafari Jozani, Kh ; Sharif University of Technology
Abstract
Molybdenum oxide nanostructures were synthesized utilizing the solution combustion method where the ammonium molybdate powder and an organic additive were used as precursors. Different organic additives including ethylene diamine tetraacetic acid (EDTA), polyethylene glycol 200 (PEG 200), sorbitol and urea were used as surfactants in order to investigate the effect of additive structure on morphology and particle size of products. Also various reaction parameters such as the additive/Mo molar ratio, concentration of metal ion in solution, pH of the reaction, and temperature of the synthesis media were changed to study effects on product morphology and size. Outcomes were characterized by...
Photovoltaic performance improvement in vacuum-assisted meniscus printed triple-cation mixed-halide perovskite films by surfactant engineering
, Article ACS Applied Energy Materials ; Volume 2, Issue 9 , 2019 , Pages 6209-6217 ; 25740962 (ISSN) ; Abdollah Zadeh, A ; Dehghani, M ; Taghavinia, N ; Sharif University of Technology
American Chemical Society
2019
Abstract
Scalable coating methods have recently emerged as practical alternative deposition techniques to the conventional spin-coating despite their lower yielding power conversion efficiencies (PCEs). The most important barrier acting against the use of scalable deposition methods to get a highly absorbing (>95%) film with controlled morphology in the high crystallinity of perovskite particles is the impossibility of antisolvent dripping during the deposition. Here, we demonstrate the positive role of both the surfactant-engineering and the vacuum-annealing (<100 Pa) process in improving the device performance to overcome this limit. A detailed optimization of the vacuum-assisted meniscus printing...
Management of soybean oil refinery wastes through recycling them for producing biosurfactant using Pseudomonas aeruginosa MR01
, Article World Journal of Microbiology and Biotechnology ; Volume 29, Issue 6 , June , 2013 , Pages 1039-1047 ; 09593993 (ISSN) ; Lotfabad, T. B ; Roostaazad, R ; Bahmaei, M ; Tayyebi, S ; Sharif University of Technology
2013
Abstract
Biosurfactant production through a fermentation process involving the biodegradation of soybean oil refining wastes was studied. Pseudomonas aeruginosa MR01 was able to produce extracellular biosurfactant when it was cultured in three soybean oil refinement wastes; acid oil, deodorizer distillate and soapstock, at different carbon to nitrogen ratios. Subsequent fermentation kinetics in the three types of waste culture were also investigated and compared with kinetic behavior in soybean oil medium. Biodegradation of wastes, biosurfactant production, biomass growth, nitrate consumption and the number of colony forming units were detected in four proposed media, at specified time intervals....
Electrochemical deposition of Ni-TiN nanocomposite coatings and the effect of sodium dodecyl sulphate surfactant on the coating properties
, Article Bulletin of Materials Science ; Volume 39, Issue 4 , 2016 , Pages 1021-1027 ; 02504707 (ISSN) ; Dolati, A ; Aghababazadeh, R ; Lalegani, Z ; Sharif University of Technology
Indian Academy of Sciences
2016
Abstract
Ni-TiN nanocomposite coatings were prepared by using electrochemical deposition in a Watt's bath containing TiN particles to increase the hardness of Ni. The effects of deposition current density, electrolyte agitation speed and the number of particles in the solution on the amount of incorporated particles in the coating process were investigated. The optimum deposition current density of 4 A dm-2 and agitation speed of 450 rpm were obtained. The effect of sodium dodecyl sulphate (SDS) anionic surfactant on the amount of particles in the coatings was investigated. It was observed that the maximum amount of incorporated particles, with a value of 7.5% by volume, was created in the current...
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...
Interactive optimization of biosurfactant production by Paenibacillus alvei ARN63 isolated from an Iranian oil well
, Article Colloids and Surfaces B: Biointerfaces ; Volume 82, Issue 1 , 2011 , Pages 33-39 ; 09277765 (ISSN) ; Rahimpour, M. R ; Jahanmiri, A. H ; Roostaazad, R ; Arabian, D ; Soleimani, M ; Jamshidnejad, Z ; Sharif University of Technology
Abstract
The potential of an indigenous bacterial strain isolated from an Iranian oil field for the production of biosurfactant was investigated in this study. After isolation, the bacterium was characterized to be Paenibacillus alvei by biochemical tests and 16S ribotyping. The biosurfactant, which was produced by this bacterium, was able to lower the surface tension of media to 35. mN/m. Accordingly, thin layer chromatography (TLC) and FT-IR has been carried out to determine compositional analysis of the produced biosurfactant. After all the tests related to characterization of the biosurfactant produced by the isolated bacterium, it was characterized as lipopeptide derivative. The combination of...
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...
Response surface methodology as an approach to optimize growth medium of indigenous strain of Bacillus mycoides for production of biosurfactant
, Article ICBEE 2010 - 2010 2nd International Conference on Chemical, Biological and Environmental Engineering, Proceedings, 2 November 2010 through 4 November 2010 ; 2010 , Pages 146-152 ; 9781424487479 (ISBN) ; Rahimpour, M. R ; Jahanmiri, A. H ; Roostaazad, R ; Arabian, D ; Soleimani, M ; Sharif University of Technology
Abstract
In this study, we have investigated the potential of a native bacterial strain isolated from an Iranian oil field for the production of biosurfactant. The bacterium was identified to be Bacillus mycoides by biochemical tests and 16S ribotyping. The biosurfactant, which was produced by this bacterium, was able to reduce the surface tension of media to 34 mN/m. Biosurfactant production was optimized by the combination of central composite design (CCD) and response surface methodology (RSM). The factor selected for optimization of growth conditions were pH, temperature, glucose and salinity concentrations. The empirical model developed through RSM in terms of effective operational factors...
Enhancing biosurfactant production from an indigenous strain of Bacillus mycoides by optimizing the growth conditions using a response surface methodology
, Article Chemical Engineering Journal ; Volume 163, Issue 3 , October , 2010 , Pages 188-194 ; 13858947 (ISSN) ; Rahimpour, M. R ; Jahanmiri, A. H ; Roostaazad, R ; Arabian, D ; Ghobadi, Z ; Sharif University of Technology
2010
Abstract
In this study, we have investigated the potential of a native bacterial strain isolated from an Iranian oil field for the production of biosurfactant. The bacterium was identified to be Bacillus mycoides by biochemical tests and 16S ribotyping. The biosurfactant, which was produced by this bacterium, was able to reduce the surface tension of media to 34. mN/m. Compositional analysis of the produced biosurfactant has been carried out by thin layer chromatography (TLC) and FT-IR. The biosurfactant produced by the isolate was characterized as lipopeptide derivative. Biosurfactant production was optimized by the combination of central composite design (CCD) and response surface methodology...
Application of different novel and newly designed commercial ionic liquids and surfactants for more oil recovery from an Iranian oil field
, Article Journal of Molecular Liquids ; Volume 230 , 2017 , Pages 579-588 ; 01677322 (ISSN) ; Ayatollahi, S ; Keshavarz, P ; Sharif University of Technology
Elsevier B.V
2017
Abstract
This investigation is conducted on one of the southern Iranian oil fields, which experiences a fault on its gas cap. Therefore, no traditional gas injection and normal water injection for pressure maintenance is suggested. The target is set to inject special compatible and proper type of chemicals in each single well to avoid the pressure increase for the risk of oil and gas spill. Two different sources of aqueous phases, namely formation brine and sea water were used to find the effects of different brine composition on the main mechanisms of releasing the trapped oil, interfacial tension (IFT) and wettability alteration. The obtained results reveal that both the ionic liquid (IL) based...
Numerical simulation of surfactant flooding in darcy scale flow
, Article Petroleum Science and Technology ; Vol. 32, Issue. 11 , 2014 , Pages 1365-1374 ; ISSN: 10916466 ; Foroughi, S ; Beiranvand, M. S ; Sharif University of Technology
Abstract
One of the methods that is used nowadays in enhanced oil recovery is surfactant flooding. The main mechanisms of surfactant flooding in reservoir consist of reduction of interfacial tension between water and oil and modification of rock wettability. In this study, the authors simulate the surfactant injection process in Darcy scale and in one-dimensional, multicomponent, multiphase state, and effects of physical phenomena such as adsorption, dispersion, convection, and exchange between fluids and solids are considered. Wettability alteration of reservoir rock due to presence of surfactant in injected fluid is detected in relative permeability and capillary pressure curves. First, the authors...
The effect of polymeric surfactant content on the mechanical properties of Al/GNP nanocomposites
, Article Materials Chemistry and Physics ; Volume 257 , 2021 ; 02540584 (ISSN) ; Abouchenari, A ; Pudine, M ; Sharifianjazi, F ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Graphene nanoplatelets (GNPs) are ideal reinforcements for improving the mechanical properties of aluminum-based matrices due to their outstanding properties. However, it essentially depends on their uniform dispersion in the matrix. In this study, the challenge of uniform dispersion of graphene was performed by functionalizing the non-covalent surface and sonication of GNPs applying non-ionic polymeric ethyl cellulose (EC) surfactant, in which a colloidal mixture was provided with Al powder and graphene, followed by sintering at 620 °C and consolidation. The density and mechanical properties of nanocomposite specimens were investigated and compared with a non-surfactant-assisted Al/GNP...
Model for excess mass-transfer resistance of contaminated liquid-liquid systems
, Article Industrial and Engineering Chemistry Research ; Volume 46, Issue 5 , 2007 , Pages 1563-1571 ; 08885885 (ISSN) ; Ghasemian, S ; Bastani, D ; Ahmadpour, N ; Sharif University of Technology
2007
Abstract
The prediction of mass-transfer rates into and from moving drops in the liquid-liquid systems has usually used the well-known Whitman two-film theory approach. According to the latter, the total resistance to mass transfer resides on each side of the interface and is described by the individual film mass-transfer coefficients for the continuous and dispersed phases in the absence of surface-active agents (contaminants). In the present work, the same approach has been used to model the excess mass-transfer resistance exerted by surface-active agents in the continuous phase. To achieve this goal, an experimental investigation has been conducted on the mass transfer into and from single drops...
Near-white emitting QD-LED based on hydrophilic CdS nanocrystals
, Article Journal of Luminescence ; Volume 132, Issue 2 , 2012 , Pages 467-473 ; 00222313 (ISSN) ; Marandi, M ; Saievar Iranizad, E ; Taghavinia, N ; Liu, B ; Sun, H. D ; Sun, X. W ; Sharif University of Technology
Abstract
In this work we report fabrication of a nanocrystal (NC)-based hybrid organicinorganic LED with structure of ITO/PEDOT:PSS/PVK/CdS-NCs/(Al or Mg:Ag). The hydrophilic CdS NCs were synthesized using a novel aqueous thermochemical method at 80 °C and sizes (around 2 nm) were controlled by thioglycolic acid (TGA) as the capping agent. The favorite feature of these NCs is their relatively high emission intensity and broad, near-white emission. The hydrophilic CdS NCs were successfully spin coated using Triton X-100 as the wetting agent. The fabricated LEDs demonstrated a turn on voltage about 7 V for Al metallic contact. The electroluminescence was a broad spectrum at 540 and 170 nm width, which...
Monitoring the effect of discontinuous shales on the surfactant flooding performance in heavy oil reservoirs using 2D glass micromodels
, Article Petroleum Science and Technology ; Vol. 32, issue. 12 , Apr , 2014 , p. 1404-1417 ; ISSN: 10916466 ; Kharrat, R ; Masihi, M ; Ghazanfari, M. H ; Saidian, M ; Sharif University of Technology
Abstract
Although most heavy oil reservoirs contain discontinuous shaly structures, there is a lack of fundamental understanding how the shaly structures affect the oil recovery efficiency, especially during surfactant flooding to heavy oils. Here, an experimental study was conducted to examine the effect of discontinuous shales on performance of surfactant flooding by introducing heterogeneities to represent streaks of shale in five-spot glass micromodels. Results show that oil recovery in presence of shale streak is lower than in its absence. Based on the authors' observations, the presence of flow barriers causes premature breakthrough of injected fluids and also an unstable displacement front. As...
Electrodeposition of Ni/WC nano composite in sulfate solution
, Article Materials Chemistry and Physics ; Volume 129, Issue 3 , 2011 , Pages 746-750 ; 02540584 (ISSN) ; Dolati, A ; Rezagholibeiki, S ; Sharif University of Technology
Abstract
Metal matrix composite coatings have gained great attention due to their exclusive properties. They have shown the properties of a metallic host material modified by addition of a second phase. In electrodeposition of Ni/WC nano composite, nickel was deposited on the substrates by DC electrodeposition in Watt's based bath containing nickel sulfate, nickel chloride, boric acid and sodium dodecyl sulfate. WC content in the coating was determined by different parameters such as current density, powder content and surfactant amount. Mechanism of electrodeposition was analyzed by cyclic voltammetry and was confirmed by Guglielmi model. Surface morphology was studied by scanning electron...