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silica
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Fabrication of a highly efficient new nanocomposite polymer gel for controlling the excess water production in petroleum reservoirs and increasing the performance of enhanced oil recovery processes
, Article Chinese Journal of Chemical Engineering ; Volume 32 , 2021 , Pages 385-392 ; 10049541 (ISSN) ; Ayatollahi, S ; ZareNezhad, B ; Sharif University of Technology
Materials China
2021
Abstract
A new nanocomposite polymer gel is synthesized for reduction of excess water production in petroleum reservoirs at real operating conditions. This new nanocomposite gel contains SiO2 nanoparticles, partially hydrolyzed polyacrylamide (HPAM) and chromium triacetate. High pressure and high temperature tests using porous carbonate core are carried out to evaluate the effects of nanoparticles on the synthesized polymer gel performance. It is shown that the residual resistance factor ratio of water to oil using the synthesized polymer gel nanocomposite in this work is much higher than that of the ordinary polymer gels. The presented results confirm the high performance of the synthesized...
Zinc-doped silica/polyaniline core/shell nanoparticles towards corrosion protection epoxy nanocomposite coatings
, Article Composites Part B: Engineering ; Volume 212 , 2021 ; 13598368 (ISSN) ; Mehmandar, E ; Jabari, H ; Ramazani Saadatabadi, A ; Mohammadkhani, R ; Yan, N ; Arjmand, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Commercial paints and coatings can serve as a protective barrier for metallic substrates in a corrosive environment. A considerable variety of nanostructures can be embedded in a polymeric coating to achieve both barrier and active protection. This research aims to elucidate the role of polyaniline (PANI) as an active polyelectrolyte modifier for the surface modification of mesoporous silica nanoparticles (MSNs) doped with zinc cations (Zn2+). To characterize the samples, we employed different techniques, including field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), N2 adsorption-desorption, Fourier transform infrared spectroscopy (FTIR), Raman...
Corrosion resistance evaluation of rebars with various primers and coatings in concrete modified with different additives
, Article Construction and Building Materials ; Volume 262 , 2020 ; Jahandari, S ; Rasekh, H ; Shariati, M ; Afshar, A ; Shokrgozar, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Corrosion of steel rebars in concrete can reduce the durability of concrete structures in coastal environments. The corrosion rate of these concrete structures can be reduced by using suitable concrete additives and coating on rebars. This paper investigates the corrosion resistance of steel rebars by the addition of pozzolanic materials including fly ash, silica fume, polypropylene fibers, and industrial 2-dimethylaminoethanol (FerroGard 901) inhibitors to the concrete mixture. Three different types of rebars including mild steel rebar st37, and two stainless steel reinforcements, AISI 304 and AISI 316, were used. Various types of primer and coating including alkyd based primer, hot-dip...
Aptamer hybrid nanocomplexes as targeting components for antibiotic/gene delivery systems and diagnostics: a review
, Article International Journal of Nanomedicine ; Volume 15 , 2020 , Pages 4237-4256 ; Arab, Z ; Safarkhani, M ; Nasseri, B ; Rabiee, M ; Tahriri, M ; Webster, T. J ; Tayebi, L ; Rabiee, N ; Sharif University of Technology
Dove Medical Press Ltd
2020
Abstract
With the passage of time and more advanced societies, there is a greater emergence and incidence of disease and necessity for improved treatments. In this respect, nowadays, aptamers, with their better efficiency at diagnosing and treating diseases than antibodies, are at the center of attention. Here, in this review, we first investigate aptamer function in various fields (such as the detection and remedy of pathogens, modification of nanoparticles, antibiotic delivery and gene delivery). Then, we present aptamer-conjugated nanocomplexes as the main and efficient factor in gene delivery. Finally, we focus on the targeted co-delivery of genes and drugs by nanocomplexes, as a new exciting...
A novel superhydrophilic/superoleophobic nanocomposite PDMS-NH2/PFONa-SiO2 coated-mesh for the highly efficient and durable separation of oil and water
, Article Surface and Coatings Technology ; Volume 394 , 2020 ; Siavash Moakhar, R ; Dolati, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A surface to separate oil–water mixtures is a global concern and highly needed particularly in oil industries. The present study was conducted to create a novel superhydrophilic/superoleophobic nanocomposite coating on the stainless-steel mesh for the aim of oil/water separation. Different hydrophilic resins along with PFOA as oleophobic agent with 15 flours in its chemical structure and various oxide nanoparticles containing SiO2 and TiO2 at different concentrations were studied to achieve superhydrophilic/superoleophobic surface. The fabricated nanocomposites were fully characterized via field-emission scanning microscopy (FESEM), atomic force microscopy (AFM) and Fourier-transform...
In situ emulsion polymerization and characterization of PVAc nanocomposites including colloidal silica nanoparticles for wood specimens bonding
, Article Journal of Applied Polymer Science ; Volume 137, Issue 15 , 2020 ; Ramezani Saadat Abadi, A ; Haddadi, S. A ; Ghaderi, S ; Azamian, F ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
Polyvinyl acetate (PVAc) nanocomposites for wood adhesives containing different amounts of colloidal silica nanoparticles (CSNs) were synthesized via in situ one-step emulsion polymerization. The adhesion strength of wood specimens bonded by PVAc nanocomposites was investigated by the tensile test. Thermal properties of PVAc nanocomposites were also characterized by differential scanning calorimetry and thermogravimetric analysis. Rheological and morphological properties of the PVAc nanocomposites were investigated using rheometric mechanical spectrometry and field emission scanning electron microscopy (FESEM), respectively. The obtaining results showed that the shear strength of PVAc...
Nano mesoporous silica for cancer treatment: ROS-responsive and redox-responsive carriers
, Article Journal of Drug Delivery Science and Technology ; Volume 57 , 2020 ; Abdekhodaie, M. J ; Behroozi, F ; Mehrvar, M ; Sharif University of Technology
Editions de Sante
2020
Abstract
Reactive oxygen species ROS and redox agents are two features of cancer medium, which could be used through responsive drug delivery systems for cancer treatment. Furthermore, mesoporous silica nanoparticles (MSNs) have special characteristics to use them in ROS-responsive and redox-responsive carriers. To shed light on this issue, we propose two drug delivery systems: 1) responsive to hydrogen peroxide (a ROS component) and 2) responsive to dithiothreitol (a redox agent). The proposed carriers are composed of 4 parts: MSNs, responsive agent (selenocystine for ROS-responsive and dithiodipropionic for the redox-responsive carrier), hyaluronic acid as the coating and targeting agent, and the...
Smart drug delivery: Capping strategies for mesoporous silica nanoparticles
, Article Microporous and Mesoporous Materials ; Volume 299 , 2020 ; Zare, H ; Razavi, S ; Mohammadi, H ; Torab Ahmadi, P ; Yazdani, N ; Bayandori, M ; Rabiee, N ; Izadi Mobarakeh, J ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Systematic delivery of therapeutic agents to specific sites, with a stimulus-responsive drug release profile is currently a rapidly growing area. Mesoporous silica nanoparticles (MSNs) are the useful platforms as drug/gene delivery systems due to their unique properties including the ability to control the pore size, high porosity, and morphology, which can directly affect the mechanism and profile of drug release. The appropriate fabrication strategy can tailor the particle shape and size, leading to enhanced delivery and release mechanisms. The MSN surface can be modified by using either organic or inorganic molecules to induce smart and site-specific drug delivery and release....
Oxidation behavior and electrical properties of de-siliconized aisi 430 alloy with mn1.5co1.5o4 coating for solid oxide fuel cell interconnect
, Article Oxidation of Metals ; Volume 93, Issue 3-4 , 2020 , Pages 401-415 ; Salmani, S ; Faghihi Sani, M. A ; Abdoli, H ; Jalili, N ; Sharif University of Technology
Springer
2020
Abstract
Abstract: The effect of de-siliconization on the oxidation behavior of AISI 430 stainless steel used for solid oxide fuel cell interconnect application was investigated. De-siliconization treatment was conducted via heating steel parts in an H2 environment. The de-siliconized substrates were then coated with a Mn1.5Co1.5O4 spinel coating, using wet spray method. For comparison, a similar coating process was applied on the as-received AISI 430 stainless steel specimens. Oxidation kinetics of coated interconnects were evaluated at 700, 800 and 900 °C in air. Results showed that the de-siliconization surface treatment decreased oxidation rates, with kinetic rates (g2 cm−4 s−1) of 4.39 × 10−14...
Propane steam reforming on mesoporous NiO–MgO–SiO2 catalysts for syngas production: Effect of the MgO/SiO2 molar ratio
, Article International Journal of Hydrogen Energy ; Volume 45, Issue 46 , 2020 , Pages 24840-24858 ; Kazemeini, M ; Rezaei, M ; Farhadi, F ; Keshavarz, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this research, a series of NiO-xMgO-SiO2 catalysts with various MgO/SiO2 molar ratios were prepared via precipitation method followed by a hydrothermal treatment in the presence of PVP as surfactant. The synergic effect between MgO and SiO2 leading to the various characteristic and catalytic performance during propane steam reforming was investigated in detail. The results showed that 15 wt% NiO-0.5MgO–SiO2 catalyst possessed the highest catalytic activity (68.9% conversion for C3H8 at 550 °C) with a negligible amount of carbon formation after 20 h of reaction duration. This superior catalytic performance can be attributed to the enhanced basicity strength along with strong metal-support...
Preparation of mesoporous nanostructure NiO–MgO–SiO2 catalysts for syngas production via propane steam reforming
, Article International Journal of Hydrogen Energy ; Volume 45, Issue 11 , 2020 , Pages 6604-6620 ; Kazemeini, M ; Farhadi, F ; Rezaei, M ; Keshavarz, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this research, the propane steam reforming (PSR) as a promising alternative route over a mesoporous NiO–MgO–SiO2 catalyst to produce syngas (SG) was undertaken. This catalyst was prepared using a co-precipitation method followed by hydrothermal treatment. The influence of such catalyst preparation factors as the hydrothermal time and temperature, pH and calcination temperature on the physicochemical characteristics of the prepared samples were examined. Next, these materials were characterized through the BET-BJH, XRD, TPR, and FTIR analyses. The thermal stability of this catalyst was tested through the TGA and DTA techniques. Furthermore, the deactivation of the calcined catalysts at...
Hydrogenated graphene oxide (H-G-SiO2) Janus structure: Experimental and computational study of strong piezo-electricity response
, Article Journal of Physics D: Applied Physics ; Volume 53, Issue 17 , 2020 ; Alidoosti, M ; Hosseinzadeh, A ; Seyyedi, S. M. S ; Elahi, M ; Pourfath, M ; Mohajerzadeh, S ; Sharif University of Technology
Institute of Physics Publishing
2020
Abstract
We have investigated the piezoelectric response of the hydrogenated graphene oxide (H-G-SiO2) stacks both experimentally and theoretically. The piezoresponse force microscopy method and density-functional theory (DFT) calculations were used to study the piezoresponse effect of this structure from both experimental and computational point of views. A mono-layer graphene, made by chemical vapour deposition method, is deposited on Si/SiO2 substrate and its surface is then functionalized with hydrogen atoms. The vertical piezoresponse, observed by piezoresponse force microscopy, is measured to be about 2146 pC N-1, that is comparable to the reported state of the art piezoelectric materials such...
Green biodiesel production from various plant oils using nanobiocatalysts under different conditions
, Article Bioenergy Research ; Volume 13, Issue 2 , 2020 , Pages 552-562 ; Kazemeini, M ; Arpanaei, A ; Sharif University of Technology
Springer
2020
Abstract
The lipase-immobilized polyethyleneimine (PEI)- and polyacrylic acid (PAA)–coated magnetic silica nanocomposite particles (L-PEI-MS and L-PAA-MS, respectively) were prepared and applied at various transesterification reaction conditions. The reactions were carried out with soybean, sunflower, canola, and palm oils along with methanol or ethanol in the solvent-free and n-hexane systems. The highest fatty acid methyl ester (FAME) and fatty acid ethyl ester (FAEE) synthesis yields were obtained from the transesterification of palm oil, i.e., almost 7.7–10.2% higher than other oils. At the constant reaction conditions, the application of ethanol leads to higher (6.0–8.7%) reaction yields in...
Micro-scale evolution of mechanical properties of glass-ceramic sealant for solid oxide fuel/electrolysis cells
, Article Ceramics International ; 2020 ; Malzbender, J ; Groß Barsnick, S. M ; Abdoli, H ; Kokabi, A. H ; Faghihi Sani, M. A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The structural integrity of the sealant is critical for the reliability of solid oxide cells (SOCs) stacks. In this study, elastic modulus (E), hardness (H) and fracture toughness (KIC) of a rapid crystallizing glass of BaO–CaO–SiO2 system termed “sealant G” are reported as determined using an indentation test method at room temperature. A wide range of indentation loads (1 mN–10 N) was used to investigate the load-dependency of these mechanical properties. Values of 95 ± 12 GPa, 5.8 ± 0.2 GPa and 1.15 ± 0.07 MPa m0.5 were derived for E, H and KIC using the most suitable indentation loads. An application relevant annealing treatment of 500 h at 800 °C does not lead to a significant change of...
A note on the synergistic effect of surfactants and nanoparticles on rising bubble hydrodynamics
, Article Chemical Engineering and Processing - Process Intensification ; Volume 155 , 2020 ; Bastani, D ; Lotfi, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Various mixtures of surfactants and nanosilica particles were investigated to assess their influence on rising bubble hydrodynamics. For this purpose, local velocities of rising bubbles were measured experimentally. Also, the effects of concentration of three types of surface-modified silica nanoparticles on density, viscosity, and surface tension of surfactant solutions were determined. Experimental results revealed that the simultaneous presence of nanoparticles and surfactant molecules led to the decrease of local velocities of rising bubbles. The presence of nanoparticles in surfactant solutions leads to a more reduction of bubble local velocity. This could be caused by the formation of...
Developing a new superhydrophilic and superoleophobic poly(4-(1-vinyl-1H-imidazol-3-ium-3-yl) butane-1-sulfonate): vinyl imidazole@Perfluorooctanoic acid@SiO2 coated stainless steel mesh for highly efficient, stable, and durable oil/water separation
, Article Journal of Coatings Technology and Research ; 2020 ; Siavash Moakhar, R ; Amirpoor, S ; Azad, M ; Dolati, A ; Sharif University of Technology
Springer
2020
Abstract
The design and development of efficient approaches for water–oil separation have had widespread interest. Most previously introduced techniques and materials used for development of the successful separation of oily wastewater could not answer all the desired demands, such as being efficient and environmentally and economically friendly. Therefore, in seeking a novel method capable of answering these expectations, surfaces with special wettability were introduced. A novel, reusable, and recyclable superhydrophilic and superoleophobic poly(Vsim-Vim)@PFOA@SiO2 nanocomposite-coated stainless steel mesh was synthesized through a facile preparation process. Since the most important factors of...
Preparation and characterization of superhydrophobic and highly oleophobic FEVE-SiO2 nanocomposite coatings
, Article Progress in Organic Coatings ; Volume 138 , 2020 ; Dolati, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Here, an excellent superhydrophobic and highly oleophobic nanocomposite coating composed of fluoroethylene-vinyl ether (FEVE) resin as a matrix for modified SiO2 nanoparticles was synthesized on a stainless-steel wire mesh substrate via a facile sol-gel method. The surface morphology, microstructure, composition, and roughness of the coatings were investigated by field emission scanning electron microscopy (FESEM) equipped with energy-dispersive spectroscopy (EDS) and atomic force microscopy (AFM). The most efficient coating with superhydrophobicity and high oleophobicity feature indicates the water and oil repellency with contact angles (CAs) of 152° and 141°, respectively, with the high...
The stability and surface activity of environmentally responsive surface-modified silica nanoparticles: the importance of hydrophobicity
, Article Journal of Dispersion Science and Technology ; Volume 41, Issue 9 , 2020 , Pages 1299-1310 ; Mohammadi, A ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
In this study, the effect of hydrophobicity of environmentally responsive surface-modified silica nanoparticles on the stability and surface activity of the nanoparticles is examined. To this end, n-propyl, n-hexyl, or n-octyl chains and methoxy poly(ethylene glycol) chains at various quantities were coated covalently on the surface of silica nanoparticles to regulate the hydrophobicity of the responsive nanoparticles. Various experimental tools such as stability analysis, interfacial-tension and contact-angle measurements, and emulsion formation were performed to investigate the effect of hydrophobicity. It became evident that the presence of the hydrophobic agents influences considerably...
Effects of surface modified nanosilica on drilling fluid and formation damage
, Article Journal of Petroleum Science and Engineering ; Volume 194 , 2020 ; Bedrikovetsky, P ; Mahani, H ; Khoshsima, A ; Aghaei, H ; Kalateh Aghamohammadi, M ; Habibi, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Despite the fact that hydrophobic nanosilica can improve the stability of water/oil emulsion, there exist controversies pertaining to its influence on oil-based drilling fluid rheological behavior and the subsequent formation damage. The present study addresses the above using a surface modified nanosilica, where the particles were functionalized with different silane-based groups to alter their hydrophilicity: 3-glycidoxypropyl-triethoxy silane (GPTS) and combined GPTS and propyl silane (PGPTS). The NPs were characterized through FTIR analysis, particle size, and zeta-potential measurements followed by flow behavior experiments, core-scale mud flow tests, Computed Tomography (CT) scanning...
Flooding numerical simulation of heterogeneous oil reservoir using different nanoscale colloidal solutions
, Article Journal of Molecular Liquids ; Volume 302 , 15 March , 2020 ; Hosseinizadeh, E ; Esfandeh, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In this study, flooding of oil reservoir by implementing Nanoscale colloidal solutions as a working fluid is simulated. All oil reservoirs are heterogeneous porous media; therefore, in this investigation for more accurate prediction of the problem, the porous media is considered heterogeneous. The governing equations of this problem are solved by finite element method (FEM). Moreover two-phase equations of Darcy and mass transfer equations are used. In this paper, the effect of temperature and volume fractions of nanoparticles on the rate of oil recovery is investigated. The SiO2, Al2O3, and CuO nanoparticles are used in the enhanced oil recovery (EOR) process. Also, in order to solve the...