Publications by authors named "Alireza Bahramian"

13 Publications

  • Page 1 of 1

Genetic algorithm based support vector machine regression for prediction of SARA analysis in crude oil samples using ATR-FTIR spectroscopy.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Jan 12;245:118945. Epub 2020 Sep 12.

Department of Statistics, Imam Khomeini International University, Qazvin, Iran.

In the current research, an analytical method was proposed for rapid quantitative determination of saturates, aromatics, resins and asphaltenes (SARA) fractions of crude oil samples. Rapid assessments of SARA analysis of crude oil samples are of substantial value in the oil industry. The conventional SARA analysis procedures were determined with the standards established by the American Society for Testing and Materials (ASTM). However, the standard test methods are time consuming, environmental nonfriendly, expensive, and require large amounts of the crude oil samples to be analyzed. Thus, it be would useful to approve some supportive approaches for rapid evaluation of the crude oils. The attenuated total reflection Fourier-transform infrared spectroscopy ATR-FTIR coupled with chemometric methods could be used as analytical method for crude oil analysis. A hybrid of genetic algorithm (GA) and support vector machine regression (SVM-R) model was applied to predict SARA analysis of crude oil samples from different Iranian oil field using ATR-FTIR spectroscopy. The result of GA-SVM-R model were compared with genetic algorithm-partial least square regression (GA-PLS-R) model. Correlation coefficient (R) and root mean square error (RMSE) for calibration and prediction of samples were also calculated, in order to evaluate the calibration models for each component of SARA analysis in crude oil samples. The performance of GA-SVM-R is found to be reliably superior, so that it can be successfully applied as an alternative approach for the quantitative determination of the SARA analysis of crude oil samples.
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http://dx.doi.org/10.1016/j.saa.2020.118945DOI Listing
January 2021

Rapid determination and classification of crude oils by ATR-FTIR spectroscopy and chemometric methods.

Spectrochim Acta A Mol Biomol Spectrosc 2020 May 16;232:118157. Epub 2020 Feb 16.

Department of Chemistry, Faculty of Science, Imam Khomeini International University, Qazvin, Iran.

Classification based on °API gravity is very important to estimate the parameters related to the extraction, purification, toxicity, and pricing of crude oils. Spectroscopy methods show some advantages over ASTM and API methods for crude oil analysis. The attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy coupled with chemometric methods has been applied as a quick and non-destructive method for crude oil analysis. In this work, a new analytical method using ATR-FTIR spectroscopy associated with chemometric methods were proposed for adressing regression and classification tasks for crude oils analysis based on °API gravity values. The designed methods are rapid, economic, and nondestructive ways in production process of oil industry. The spectral data were used for estimation of °API gravity using two approaches according to PLS-R and SVM-R algorithm, separately. The ATR-FTIR spectral data were also analyzed by classification method using the partial least squares-discriminant analysis (PLS-DA) for crude oil classification. The samples were classified into three classes based on their °API gravity values. The SVM-R model showed better results than PLS-R for °API gravity values using the F-test at 95% of confidence. The result of classification, showed about 100% accuracy and a zero classification error for calibration and prediction samples in PLS-DA algorithm.
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http://dx.doi.org/10.1016/j.saa.2020.118157DOI Listing
May 2020

Visual deprivation is met with active changes in ground reaction forces to minimize worsening balance and stability during walking.

Exp Brain Res 2020 Feb 11;238(2):369-379. Epub 2020 Jan 11.

Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran.

Previous studies suggest that visual information is essential for balance and stability of locomotion. We investigated whether visual deprivation is met with active reactions tending to minimize worsening balance and stability during walking in humans. We evaluated effects of vision on kinetic characteristics of walking on a treadmill-ground reaction forces (GRFs) and shifts in the center of mass (COM). Young adults (n = 10) walked on a treadmill at a comfortable speed. We measured three orthogonal components of GRFs and COM shifts during no-vision (NV) and full-vision (FV) conditions. We also computed the dynamic balance index (D)-the perpendicular distance from the projection of center of mass (pCOM) to the inter-foot line (IFL) normalized to half of the foot length. Locally weighted regression smoothing with alpha-adjusted serial T tests was used to compare GRFs and D between two conditions during the entire stance phase. Results showed significant differences in GRFs between FV and NV conditions in vertical and ML directions. Variability of peak forces of all three components of GRF increased in NV condition. We also observed significant increase in D for NV condition in eight out of ten subjects. The pCOM was kept within BOS during walking, in both conditions, suggesting that body stability was actively controlled by adjusting three components of GRFs during NV walking to minimize stability loss and preserve balance.
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http://dx.doi.org/10.1007/s00221-020-05722-0DOI Listing
February 2020

Synthesis and physicochemical properties of dual-responsive acrylic acid/butyl acrylate cross-linked nanogel systems.

J Colloid Interface Sci 2019 Nov 20;556:313-323. Epub 2019 Aug 20.

Department of Chemical Engineering, College of Engineering, University of Tehran, 11155/4563 Tehran, Iran. Electronic address:

Hypothesis: A cross-linked amphiphilic nanogel containing a high mole% of hydrophilic pH-responsive moiety can provide enhanced functionality regarding stimuli-responsiveness, water-dispersibility, hydrophobic substance loading, and structural stability under harsh environmental conditions. These nanogels could be synthesized using a one-pot procedure for large-scale applications. Moreover, the interplay of various interaction forces in these colloidal systems is being investigated.

Experiments: Model nanogels consisting of acrylic acid-butyl acrylate-ethylene glycoldimethacrylate were synthesized using an emulsion copolymerization via a seeded semi-batch process under an acidic condition. The structures were assessed by Fourier transform infrared spectroscopy and potentiometric-conductometric titrations. Zeta potential, field-emission scanning electron microscopy, and transmission electron microscopy were used to evaluate the dispersion stability, size distribution, and structural distribution, respectively. Their stimuli-responsive behavior was studied by combining static and dynamic light scattering and titration analyses.

Findings: Monodisperse nanospheres of approximately 150 nm were successfully prepared by implementing a one-pot practical pathway. These nanogels displayed a dual thermo- and pH-responsive behavior, reflecting the high efficiency of physical cross-linking make it ideal for drug delivery and oil industry applications. Moreover, a novel symmetric pH-activated morphology transformation behavior was revealed. Accordingly, a compositional distribution was proposed and assessed by exploring the polymerization process.
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http://dx.doi.org/10.1016/j.jcis.2019.08.066DOI Listing
November 2019

Influence of hydrophilic silica nanoparticles on the adsorption layer properties of non-ionic surfactants at water/heptane interface.

J Colloid Interface Sci 2019 Jun 14;545:242-250. Epub 2019 Mar 14.

Institute of Petroleum Engineering, Chemical Engineering Department, University of Tehran, Iran.

There is a notable paucity of studies investigating the impact of charged nanoparticles on the interfacial behavior of nonionic surfactants, assuming that the interactions are negligible in the absence of electrostatic forces. Here, we argue about our observations and the existence of a complex interfacial behavior in such systems depending on the type and chemical structure of surfactant. This study set out to investigate the effects of interactions between hydrophilic silica nanoparticles (NP) and non-ionic surfactants on water/heptane dynamic interfacial properties using drop profile analysis tensiometry (PAT). Three surfactants were studied, namely Triton X-100 (significantly soluble in water phase), CDMPO (well soluble in both phases) and SPAN 80 (oil-soluble). The different chemical structures and partition coefficients of the surfactants enabled us to cover possible interactions and differentiate between bulk and interfacial interactions. We observed that hydrophilic silica NPs had a negligible effect on the interfacial behavior of Triton X-100, that they increased the surface activity of CDMPO when both compounds are initially in the aqueous phase. Most interestingly is that the added NPs generated unstable interfacial NP-surfactant complexes and reduced the pseudo-equilibrium interfacial tension of oil-soluble surfactant, Span 80, even though NPs and surfactants were in different bulk phases.
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http://dx.doi.org/10.1016/j.jcis.2019.03.047DOI Listing
June 2019

The Role of Electrostatic Repulsion on Increasing Surface Activity of Anionic Surfactants in the Presence of Hydrophilic Silica Nanoparticles.

Sci Rep 2018 May 8;8(1):7251. Epub 2018 May 8.

Max-Planck-Institute for Colloid and Interface Science, D-14476, Golm, Germany.

Hydrophilic silica nanoparticles alone are not surface active. They, however, develop a strong electrostatic interaction with ionic surfactants and consequently affect their surface behavior. We report the interfacial behavior of n-heptane/anionic-surfactant-solutions in the presence of hydrophilic silica nanoparticles. The surfactants are sodium dodecyl sulfate (SDS) and dodecyl benzene sulfonic acid (DBSA), and the diameters of the used particles are 9 and 30 nm. Using experimental tensiometry, we show that nanoparticles retain their non-surface-active nature in the presence of surfactants and the surface activity of surfactant directly increases with the concentration of nanoparticles. This fact was attributed to the electrostatic repulsive interaction between the negatively charged nanoparticles and the anionic surfactant molecules. The role of electrostatic repulsion on increasing surface activity of the surfactant has been discussed. Further investigations have been performed for screening the double layer charge of the nanoparticles in the presence of salt. Moreover, the hydrolysis of SDS molecules in the presence of silica nanoparticles and the interaction of nanoparticles with SDS inherent impurities have been studied. According to our experimental observations, silica nanoparticles alleviate the effects of dodecanol, formed by SDS hydrolysis, on the interfacial properties of SDS solution.
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http://dx.doi.org/10.1038/s41598-018-25493-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5940767PMC
May 2018

Superamphiphobic Surfaces Prepared by Coating Multifunctional Nanofluids.

ACS Appl Mater Interfaces 2016 Nov 10;8(46):32011-32020. Epub 2016 Nov 10.

School of Biological and Chemical Sciences, Queen Mary, University of London , Joseph Priestley Building, Mile End Road, London E1 4NS, United Kingdom.

Construction of surfaces with the capability of repelling both water and oil is a challenging issue. We report the superamphiphobic properties of mineral surfaces coated with nanofluids based on synthesized Co-doped and Ce-doped Barium Strontium Titanate (CoBST and CeBST) nanoparticles and fluorochemicals of trichloro(1H,1H,2H,2H-perfluorooctyl)silane (PFOS) and polytetrafluoroethylene (PTFE). Coating surfaces with these nanofluids provides both oil (with surface tensions as low as 23 mN/m) and water repellency. Liquids with high surface tension (such as water and ethylene glycol) roll off the coated surface without tilting. A water drop released from 8 mm above the coated surface undergoes first a lateral displacement from its trajectory and shape deformation, striking the surface after 23 ms, bouncing and rolling off freely. These multifunctional coating nanofluids impart properties of self-cleaning. Applications include coating surfaces where cleanliness is paramount such as in hospitals and domestic environments as well as the maintenance of building facades and protection of public monuments from weathering. These superamphiphobic-doped nanofluids have thermal stability up to 180 °C; novel industrial applications include within fracking and the elimination of condensate blockage in gas reservoirs.
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http://dx.doi.org/10.1021/acsami.6b10913DOI Listing
November 2016

Interfacial equation of state for ionized surfactants at oil/water interfaces.

Soft Matter 2015 Aug 17;11(32):6482-91. Epub 2015 Jul 17.

Institute of Petroleum Engineering, University of Tehran, Tehran, Iran.

A new mathematical approach has been developed for describing the interfacial behaviour of oil/water interfaces in the presence of ionic surfactants. The approach relies on the ideal behaviour of ionized surfactants at oil/water interfaces, which is previously demonstrated by Lucassen-Reynders (J. Phys. Chem., 1966, 70, 1777-1785). The new derived equation simply relates the interfacial tension to the surfactant molecular size and the cmc value of the surfactant in the aqueous phase. The predicted values are in a reasonable agreement with the measured experimental data. Formation of complex multi-layers is considered and the related development is performed. It is shown that, assuming a multi-layer interface, the proposed model gives an area per surfactant molecule similar to the values obtained by techniques such as neutron reflectivity (NR), while a monolayer assumption yields about half the value. The discussion describes the impact of dissolved oil and ionic components on the interfacial tension of the ionized surfactants at oil/water interfaces.
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http://dx.doi.org/10.1039/c5sm01406aDOI Listing
August 2015

The adsorption behavior of ionic surfactants and their mixtures with nonionic polymers and with polyelectrolytes of opposite charge at the air-water interface.

J Phys Chem B 2014 Mar 5;118(10):2769-83. Epub 2014 Mar 5.

Institute of Petroleum Engineering, University of Tehran , P.O. Box 11155-4563, Tehran, Iran.

The surface phase approach of Butler has been used to derive a model of the surface tension (ST) of surfactant solutions in terms of the ST of the surfactant in the absence of water, an area parameter corresponding approximately to the limiting area per molecule, and the critical micelle concentration (CMC). This isotherm is then used to account for the ST behavior of aqueous solutions of weakly interacting polymer-surfactant (P-S) and strongly interacting polyelectrolyte-surfactant (PE-S) mixtures. For P-S systems, no additional parameters are required other than the critical aggregation concentration (CAC) and the onset of the ST plateau at micellization (T3). The model accounts for experimental isotherms for sodium dodecyl sulfate (SDS) with poly(ethylene oxide) or poly(vinylpyrrolidone). For PE-S systems, the initial CAC has no effect on the ST and is well below the decrease in ST that leads to the first ST plateau at T1. This decrease is modeled approximately using a Langmuir isotherm. The remaining ST behavior is analyzed with the model surfactant isotherm and includes modeling the ST when there is separation into two phases. The behavior in the phase separation region depends on the dissociability of the PE-S complex. Loss of surface activity accompanied by a peak in the ST may occur when there is part formation of a nondissociable complex (neutral with segment/surfactant = 1). The model successfully explains the ST of several experimental systems with and without ST peaks, including poly(dimethyldiallylammonium chloride)-SDS and poly(sodium styrenesulfonate)-alkyltrimethylammonium bromide (C(n)TAB) with n = 12, 14, and 16.
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http://dx.doi.org/10.1021/jp500672fDOI Listing
March 2014

Asphaltene adsorption onto acidic/basic metal oxide nanoparticles toward in situ upgrading of reservoir oils by nanotechnology.

Langmuir 2013 Nov 5;29(46):14135-46. Epub 2013 Nov 5.

Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, College of Engineering, University of Tehran , P.O. Box 11155/4563, Tehran, Iran.

The effects of surface acidity and basicity of metal oxide nanoparticles on the thermodynamics of asphaltene adsorption were studied. Three different categories of metal oxides/salts with acidic (WO3 and NiO), amphoteric (Fe2O3 and ZrO2), and basic (MgO and CaCO3) surfaces were synthesized, and their textural, structural, and acid-base properties were characterized. Asphaltenes were extracted from a dead oil sample and characterized by X-ray powder diffraction and Fourier transform infrared spectroscopy. The acid and base numbers of the asphaltenes were measured. The nanoparticles were added to the asphaltene-toluene solutions, and the amount of adsorbed asphaltene was obtained through centrifugation followed by UV-vis spectroscopy of the supernatant liquid and temperature-programmed oxidation analysis of the precipitated solid. The concentrations of organic acid and base groups in the asphaltenes are 2.75 and 12.34 mg of KOH/g, respectively, indicating that the asphaltenes are more basic in nature. Isotherms of the asphaltene adsorption onto the six metal oxides/salts fit the Langmuir model closely. The asphaltene adsorption capacity of the nanoparticles is 1.23-3.67 mg/m(2) and decreases in the order of NiO > Fe2O3 > WO3 > MgO > CaCO3 > ZrO2, concomitant with the synergetic effects of acidity and the net charge of the surfaces. High-resolution transmission electron microscopy illustrates that the asphaltenes are spread out over the surfaces with no short-range/long-range order. The adsorption of the asphaltenes onto the six samples is exothermic and spontaneous with the Gibbs energy change of -27.80 to -28.79 kJ/mol at 25 °C. The absolute value of the enthalpy change of the adsorption is calculated to be within the range of 5-20 kJ/mol. Acid-base interaction and electrostatic attraction seem to be the dominant forces contributing to the adsorption of the asphaltenes onto the metal oxide/salt surfaces.
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http://dx.doi.org/10.1021/la402979hDOI Listing
November 2013

Surface behavior, aggregation and phase separation of aqueous mixtures of dodecyl trimethylammonium bromide and sodium oligoarene sulfonates: the transition to polyelectrolyte/surfactant behavior.

Langmuir 2012 Jan 30;28(1):327-38. Epub 2011 Nov 30.

Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China.

The properties and phase diagrams of aqueous mixtures of dodecyltrimethylammonium bromide (C(12)TAB) with the sodium oligoarene sulphonates (POSn), POS2, POS3, POS4, and POS6 have been studied using surface tension and neutron reflectometry to study the surface, and neutron small angle scattering and fluorescence to study the bulk solution. The behavior of POS2 and POS3 is reasonably consistent with mixed micelles of C(12)TAB and POSn-(C(12)TA)(n). These systems exhibit a single critical micelle concentration (CMC) at which the surface tension reaches the usual plateau. This is contrary to a recent report which suggests that the onset of the surface tension plateau does not coincide with the CMC. In the POS3 system, the micelles conform to the core-shell model, are slightly ellipsoidal, and have aggregation numbers in the range 70-100. In addition, the dissociation constant for ionization of the micelles is significantly lower than for free C(12)TAB micelles, indicating binding of the POS3 ion to the micelles. Estimation of the CMCs of the POSn-(C(12)TA)(n) from n = 1-3 assuming ideal mixing of the two component surfactants and the observed values of the mixed CMC gives values that are consistent with the nearest related gemini surfactant. The POS4 and POS6 systems are different. They both phase separate slowly to form a dilute and a concentrated (dense) phase. Fluorescence of POS4 has been used to show that the onset of aggregation of surfactant (critical aggregation concentration, CAC) occurs at the onset of the surface tension plateau and that, at the slightly higher concentration of the phase separation, the concentration of POS4 and C(12)TAB in the dilute phase is at or below its concentration at the CAC, that is, this is a clear case of complex coacervation. The surface layer of the C(12)TA ion in the surface tension plateau region, studied directly by neutron reflectometry, was found to be higher than a simple monolayer (observed for POS2 and POS3) for both the POS4 and POS6 systems. In POS6 this evolved after a few hours to a structure consisting of a monolayer with an attached subsurface bilayer, closely resembling that observed for one class of polyelectrolyte/surfactant mixtures. It is suggested that this structured layer, which must be present on the surface of the dilute phase of the coacervated system, is a thin wetting film of the dense phase. The close resemblance of the properties of the POS6 system to that of one large group of polyelectrolyte/surfactant mixtures shows that the surface behavior of oligoion/surfactant mixtures can quickly become representative of that of true polyelectrolyte/surfactant mixtures. In addition, the more precise characterization possible for the POS6 system identifies an unusual feature of the surface behavior of some polyelectrolyte/surfactant systems and that is that the surface tension can remain low and constant through a precipitation/coacervation region because of the characteristics of two phase wetting. The well-defined fixed charge distribution in POS6 also suggests that rigidity and charge separation are the factors that control whether a given system will exhibit a flat surface tension plateau or the alternative of a peak on the surface tension plateau.
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http://dx.doi.org/10.1021/la2040938DOI Listing
January 2012

Prediction of solid-water-hydrocarbon contact angle.

J Colloid Interface Sci 2007 Jul 20;311(2):579-86. Epub 2007 Mar 20.

Institute of Petroleum Engineering, University of Tehran, Tehran, Iran.

The reliability of a recently developed solid-vapour and solid-liquid interfacial tension models has been investigated by applying them to predict liquid-vapour and liquid-liquid interfacial tension values. The impact of the geometrical molecular packing and the molecular orientations near the surface on the predicted values are discussed. The mutual solubility data are shown to be adequate for calculation of the interaction parameters in the solid-liquid model and a new equation, using this information, is developed for prediction of water-hydrocarbon interfacial tension. The model has been applied to recent data on water-methane-n-decane and water-methane-cyclohexane-n-decane interfacial tensions at elevated temperature and pressure and its reliability demonstrated. It is shown that the solid-liquid interfacial tension model is solely adequate for predicting the contact angle by applying it to mercury-water-benzene and stearic acid-water-n-decane systems.
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http://dx.doi.org/10.1016/j.jcis.2007.03.019DOI Listing
July 2007

Prediction of solid-fluid interfacial tension and contact angle.

J Colloid Interface Sci 2004 Nov;279(1):206-12

Institute of Petroleum Engineering, University of Tehran, Iran.

Two simple equations have been developed using the lattice theory and the regular solution assumption to predict the solid-vapor and solid-liquid interfacial tension. The required parameters are the liquid critical temperature and volume, the solid melting temperature and the molar volume of liquid and solid compounds. To confirm the models, the predicted solid-fluid interfacial tension values have been used to predict the contact angle of the liquid drop on the solid surface applying Young's equation. Agreement of the predicted contact angle with the experimental data reveals the reliability of the developed models.
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http://dx.doi.org/10.1016/j.jcis.2004.06.058DOI Listing
November 2004