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The effect of pore morphology and agarose coating on mechanical properties of tricalcium phosphate scaffolds
, Article International Journal of Applied Ceramic Technology ; Volume 19, Issue 5 , 2022 , Pages 2713-2722 ; 1546542X (ISSN) ; Bagheri, R ; Amirkhani, S ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Three-dimensional biocompatible porous structures can be fabricated using different methods. However, the biological and mechanical behaviors of scaffolds are the center of focus in bone tissue engineering. In this study, tricalcium phosphate scaffolds with similar porosity contents but different pore morphologies were fabricated using two different techniques, namely, the replica method and the pore-forming agent method. The samples fabricated using the pore-forming agent showed more than two times higher compressive and bending strengths and more than three times higher compressive moduli. Furthermore, a thin layer of agarose coating improved the compressive and bending strength of both...
simulation of thermo-hydro-mechanical processes at Soultz-sous-Forêts
, Article Energies ; Volume 15, Issue 24 , 2022 ; 19961073 (ISSN) ; Singh, M ; Mahyapour, R ; Tangirala, S. K ; Bär, K ; Sass, I ; Sharif University of Technology
MDPI
2022
Abstract
Porosity and permeability alteration due to the thermo-poro-elastic stress field disturbance from the cold fluid injection is a deciding factor for longer, more economic, and safer heat extraction from an enhanced geothermal system (EGS). In the Soultz-sous-Forêts geothermal system, faulted zones are the main flow paths, and the resulting porosity–permeability development over time due to stress reorientation is more sensitive in comparison with the regions without faulted zones. Available operational and field data are combined through a validated numerical simulation model to examine the mechanical impact on the pressure and temperature evolution. Results shows that near the injection...
Impact of temperature and etching methods on surface roughness, topography, and composition of glass micromodels
, Article Energy and Fuels ; Volume 36, Issue 23 , 2022 , Pages 14066-14078 ; 08870624 (ISSN) ; Masihi, M ; Mahani, H ; Tamsilian, Y ; Sharif University of Technology
American Chemical Society
2022
Abstract
Fluid flow in porous media is affected by surface characteristics such as roughness and topography. In this work, to simulate the surface of natural porous structures in transparent interconnected media like micromodels, various degrees of roughness have been artificially created on flat glass substrates via different methods of laser ablation, cream etching, combination of laser ablation and cream etching, and hydrofluoric acid (HF) etching. The obtained surfaces by each method were characterized in detail via field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX/EDS), and surface profilometry. The impact of high...
A novel method for measuring the porosity of the nanowebs
, Article Results in Materials ; Volume 16 , 2022 ; 2590048X (ISSN) ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Nanofiber layers have exciting properties such as fine fiber diameter, small pores, suitable connectivity between pores, high surface area and high porosity. These properties make nanofibers applicable for a variety of applications, such as high-performance filters and tissue engineering scaffolds. Different applications of electrospinning layers require different porosities. Therefore, it is very important to measure the porosity of nanofiber layers to express their application. To date, many methods have been expressed for this purpose, but all methods have disadvantages. Therefore, finding the best method is a challenge that will be addressed in this project. © 2022 The Author
Investigation on reactive flow through porous media by quadtree Lattice Boltzmann
, Article Journal of Natural Gas Science and Engineering ; Volume 104 , 2022 ; 18755100 (ISSN) ; Ayatollahi, S ; Jamshidi, S ; Raoof, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this study, in order to investigate the effect of the underlying pore-scale processes on continuum scale simulations of porous media dissolution, we improve the standard Lattice Boltzmann method using Quadtree grid refinement approach to simulate fluid flow and reactive transport through large domain sizes. Our results have shown considerable computational improvements up to 80% in simulation time together with increased numerical accuracy. The results and the added value of the new approach are discussed using comparison of our model with the conventional LBM. Moreover, we have applied a systematic analysis by increasing complexity levels and starting from fluid flow and continuing with...
Synergy of titanium dioxide nanotubes and polyurethane properties for bypass graft application: Excellent flexibility and biocompatibility
, Article Materials and Design ; Volume 215 , 2022 ; 02641275 (ISSN) ; Bagheri, R ; Pourjavadi, A ; Ghanbari, H ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
A flexible, porous and biocompatible titanium dioxide nanotubes (TNT) - polyurethane (PU) film has been produced as a new scaffold for artificial vascular grafts. Synergistic improvements in the properties of vertical TNT and PU was reached, including enhancements in their biocompatibility, mechanical strength, flexibility and porosity. Open-ended (OE) TNT-PU and close-ended (CE) TNT-PU films were synthesized and their mechanical and biological properties were compared with their pure PU counterparts. TNT were attached to PU with a new strategy. The resulting flexible structure was hydrophilic and super hydrophilic in OE-TNT-PU and CE-TNT-PU scaffolds, respectively. The gas leakage during...
Hyperbranched polyethylenimine functionalized silica/polysulfone nanocomposite membranes for water purification
, Article Chemosphere ; Volume 290 , 2022 ; 00456535 (ISSN) ; Jouyandeh, M ; Akhi, H ; Mousavi Khadem, S. S ; Ganjali, M. R ; Moradi, H ; Mirsadeghi, S ; Badiei, A ; Esmaeili, A ; Rabiee, N ; Habibzadeh, S ; Koyuncu, I ; Nouranian, S ; Formela, K ; Saeb, M. R ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Hyperbranched polyethyleneimine functionalized silica (PEI-SiO2) nanoparticles with considerable hydrophilicity were synthesized and incorporated into a polysulfone (PSF)/dimethylacetamide (DMA)/polyvinylpyrrolidone (PVP) membrane casting solution in five different ratios to fabricate PEI-SiO2/PSF nanocomposite membranes using nonsolvent-induced phase separation. The hydrophilic PEI-SiO2 nanoparticles were characterized by TEM, FTIR, TGA, and XPS analyses. Morphology, water contact angles, mean pore sizes, overall porosity, tensile strengths, water flux, antifouling and the dye separation performances of the PEI-SiO2/PSF membranes were also studied. The PEI-SiO2 nanoparticles were uniformly...
Fabrication and performance of polysulfone/H2O2-g-C3N4 mixed matrix membrane in a photocatalytic membrane reactor under visible light irradiation for removal of natural organic matter
, Article Separation and Purification Technology ; Volume 285 , 2022 ; 13835866 (ISSN) ; Heydari, H ; Khansanami, M ; Vatanpour, V ; Mousavi, S. A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The coupling of photocatalysis with membrane technology, which is known as photocatalytic membrane reactors (PMRs), has received great consideration in recent years and become a promising approach with the high potential to improve the fouling of membranes. In this paper, the photocatalyst of g-C3N4 treated with H2O2 was incorporated with a polysulfone membrane to enhance the anti-fouling properties of the membrane. AFM, FE-SEM images, porosity, and contact angle analysis indicated that the membrane properties like hydrophilicity, porosity, and surface roughness were improved. Also, UV–visible DRS, PL spectra, EIS analysis confirmed that the treated g-C3N4 (H2O2-g-C3N4) had high light...
Modeling the dual-fuel combustion of porous lycopodium particles and diesel using an analytical simulation framework
, Article Journal of Analytical and Applied Pyrolysis ; Volume 163 , 2022 ; 01652370 (ISSN) ; Akbari, S ; Faghiri, S ; Sadeghi, S ; Xu, F ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this paper, a comprehensive analytical study is performed to assess the lycopodium-diesel dual-fuel combustion system in counter-flow premixed configuration. The system is modeled as multiple zones that are coupled together via proper boundary and jump conditions on interfaces. According to the respective reaction and transport phenomena in these zones, conservation equations of mass and energy are derived, non-dimensionalized, and solved by Matlab and Mathematica in an analytical way. The porosity of lycopodium particles and the thermal radiation from the reaction zone and the post-flame zones into the preheating zone are considered, in order to improve the realism and accuracy of the...
Fluid flow and heat transfer in microchannel with and without porous medium under constant heat flux
, Article Sadhana - Academy Proceedings in Engineering Sciences ; Volume 47, Issue 2 , 2022 ; 02562499 (ISSN) ; Sharif University of Technology
Springer
2022
Abstract
In this study, the heat transfer and fluid flow characteristics of a three-dimensional microchannel that is partially filled with a layer of porous medium at its bottom solid wall is investigated. The microchannel is consisted of a clear fluid flow region, solid walls and a porous layer that is attached to its solid bottom wall. A constant heat flux is applied to the bottom wall of the microchannel. Darcy-Brinkman-Forchheimer model is used to simulate the fluid flow inside the porous medium. The novelty of this work is to investigate thoroughly and precisely the effect of using of porous layer configuration in MCHSs on hydraulic and thermal performances. The effect of porous layer thickness,...
DNAPL flow and complex electrical resistivity evolution in saturated porous media: A coupled numerical simulation
, Article Journal of Contaminant Hydrology ; Volume 248 , 2022 ; 01697722 (ISSN) ; Deparis, J ; Leroy, P ; Ataie Ashtiani, B ; Davarzani, H ; Colombano, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Induced Polarization (IP) is a non-intrusive geophysical method to monitor Dense Non-Aqueous Phase Liquid (DNAPL) contamination and remediation processes underground. In this study, an advanced numerical code simulating DNAPL flow and complex electrical resistivity is presented. The model was validated against existing IP results and image measurements that were carried out previously in a series of 2D tank experiment. Multiphase flow modeling in porous media is coupled with electrical current modeling to simulate the process of DNAPL migration and the associated IP response. This brings a broader view of the contamination in space and time compared to surface and borehole measurements,...
Bioactive hybrid metal-organic framework (MOF)-based nanosensors for optical detection of recombinant SARS-CoV-2 spike antigen
, Article Science of the Total Environment ; Volume 825 , 2022 ; 00489697 (ISSN) ; Fatahi, Y ; Ahmadi, S ; Abbariki, N ; Ojaghi, A ; Rabiee, M ; Radmanesh, F ; Dinarvand, R ; Bagherzadeh, M ; Mostafavi, E ; Ashrafizadeh, M ; Makvandi, P ; Lima, E. C ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Fast, efficient, and accurate detection of SARS-CoV-2 spike antigen is pivotal to control the spread and reduce the mortality of COVID-19. Nevertheless, the sensitivity of available nanobiosensors to detect recombinant SARS-CoV-2 spike antigen seems insufficient. As a proof-of-concept, MOF-5/CoNi2S4 is developed as a low-cost, safe, and bioactive hybrid nanostructure via the one-pot high-gravity protocol. Then, the porphyrin, H2TMP, was attached to the surface of the synthesized nanomaterial to increase the porosity for efficient detection of recombinant SARS-CoV-2 spike antigen. AFM results approved roughness in different ranges, including 0.54 to 0.74 μm and 0.78 to ≈0.80 μm, showing good...
Efficacy of a novel bioactive glass-polymer composite for enamel remineralization following erosive challenge
, Article International Journal of Dentistry ; Volume 2022 , 2022 ; 16878728 (ISSN) ; Heidari, S ; Najafi, F ; Hajihasani, M ; Noshiri, N ; Nazari, N. F ; Sharif University of Technology
Hindawi Limited
2022
Abstract
Introduction. Dental caries is the most common cause of tooth loss. However, it can be stopped by enhancing remineralization. Fluoride and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) are among the most important remineralizing agents. Recent studies have used bioactive glass as a remineralizing agent in different forms. This study aimed to assess the efficacy of a composite paste (prepared by mixing urethane polypropylene glycol oligomer with bioactive glass powder for easier application). Materials and Methods. Enamel disks were cut out of the buccal surface of extracted sound third molars. The samples were randomly divided into 3 groups of 15 and underwent Vickers...
Thermal and hydraulic performance of rectangular microchannel heat sinks with trapezoidal porous configuration
, Article Numerical Heat Transfer; Part A: Applications ; Volume 81, Issue 3-6 , 2022 , Pages 72-93 ; 10407782 (ISSN) ; Vafai, K ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
In this article, the thermal and hydraulic capacity of a rectangular microchannel heat sink with different trapezoidal porous configuration’s inlet heights (Formula presented.) and outlet heights (Formula presented.) are examined. A three-dimensional model is used for microchannels with miscellaneous trapezoidal porous configuration’s inlet and outlet heights, and the laminar fluid flow and conjugate heat transfer equations are numerically solved. Darcy-Brinkmen-Forchheimer equation is utilized for transport through the porous region. For microchannels with miscellaneous porous distribution’s inlet and outlet heights, the Nusselt number, pressure drop and figure of merit (FOM), a criterion...
Nonlinear free vibration analysis of in-plane Bi-directional functionally graded plate with porosities resting on elastic foundations
, Article International Journal of Applied Mechanics ; Volume 14, Issue 1 , 2022 ; 17588251 (ISSN) ; Shahri, P. K ; Beigzadeh, S ; Zamani, F ; Eratbeni, M. G ; Mahdavi, M ; Heidari, A ; Khaledi, H ; Abadi, M. R. R ; Sharif University of Technology
World Scientific
2022
Abstract
This paper deals with the nonlinear free vibration analysis of in-plane bi-directional functionally graded (IBFG) rectangular plate with porosities which are resting on Winkler-Pasternak elastic foundations. The material properties of the IBFG plate are assumed to be graded along the length and width of the plate according to the power-law distribution, as well as, even and uneven types are taken into account for porosity distributions. Equations of motion are developed by means of Hamilton's principle and von Karman nonlinearity strain-displacement relations based on classical plate theory (CPT). Afterward, the time-dependent nonlinear equations are derived by applying the Galerkin...
Biological activated carbon process for biotransformation of azo dye carmoisine by klebsiella spp
, Article Environmental Technology (United Kingdom) ; Volume 43, Issue 18 , 2022 , Pages 2713-2729 ; 09593330 (ISSN) ; Bagheri Lotfabad, T ; Heydarinasab, A ; Yaghmaei, S ; Mohseni, F. A ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
The feasibility of employing the biological activated carbon (BAC) process to debilitate azo dye Carmoisine by Klebsiella spp. was investigated. Plate assay revealed the capability of Klebsiella spp. for removal of Carmoisine via degradation. Kinetic parameters were measured for Carmoisine debilitation by Klebsiella spp. using the suspended anaerobic process. Two types of granular and rod-shaped activated carbon were used to form the biological beds in order to study the Carmoisine debilitation in batch processes. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to indicate the colonization and biofilm formation of bacteria grown on activated carbon...
Green porous benzamide-like nanomembranes for hazardous cations detection, separation, and concentration adjustment
, Article Journal of Hazardous Materials ; Volume 423 , 2022 ; 03043894 (ISSN) ; Fatahi, Y ; Asadnia, M ; Daneshgar, H ; Kiani, M ; Ghadiri, A. M ; Atarod, M ; Mashhadzadeh, A. H ; Akhavan, O ; Bagherzadeh, M ; Lima, E. C ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Green biomaterials play a crucial role in the diagnosis and treatment of diseases as well as health-related problem-solving. Typically, biocompatibility, biodegradability, and mechanical strength are requirements centered on biomaterial engineering. However, in-hospital therapeutics require an elaborated synthesis of hybrid and complex nanomaterials capable of mimicking cellular behavior. Accumulation of hazardous cations like K+ in the inner and middle ear may permanently damage the ear system. We synthesized nanoplatforms based on Allium noeanum to take the first steps in developing biological porous nanomembranes for hazardous cation detection in biological media. The...
Preparation of novel and highly active magnetic ternary structures (metal-organic framework/cobalt ferrite/graphene oxide) for effective visible-light-driven photocatalytic and photo-fenton-like degradation of organic contaminants
, Article Journal of Colloid and Interface Science ; Volume 602 , 2021 , Pages 73-94 ; 00219797 (ISSN) ; Kazemeini, M ; Mahmoodi, N. M ; Sharif University of Technology
Academic Press Inc
2021
Abstract
Herein, MIL-101(Fe), CoFe2O4, novel binary (MIL-101(Fe)/CoFe2O4, MIL-101(Fe)/GO and CoFe2O4/GO), and ternary (MIL-101(Fe)/CoFe2O4/(3%)GO and MIL-101(Fe)/CoFe2O4/(7%)GO) magnetic composites based upon the MIL-101(Fe) were synthesized. The XRD, FESEM, TEM, EDX, BET-BJH, FTIR, VSM, DRS, PL, EIS and other electrochemical analyses were applied to characterize samples. The MIL/CoFe2O4/(3%)GO demonstrated the best performance compared to other samples for visible light photocatalytic and photo-Fenton-like degradation of Direct Red 23 (DtR-23), Reactive Red 198 (ReR-198) dyes as well as Tetracycline Hydrochloride (TC-H) antibiotic. Degradation of dyes using the ternary composite after 70 min of...
High yield of CO and synchronous s recovery from the conversion of CO2 and H2S in natural gas based on a novel electrochemical reactor
, Article Environmental Science and Technology ; Volume 55, Issue 21 , 2021 , Pages 14854-14862 ; 0013936X (ISSN) ; Zhang, B ; Zhang, Y ; Zhou, C ; Wang, P ; Zha, L ; Li, J ; Simchi, A ; Zhou, B ; Sharif University of Technology
American Chemical Society
2021
Abstract
H2S and CO2 are the main impurities in raw natural gas, which needs to be purified before use. However, the comprehensive utilization of H2S and CO2 has been ignored. Herein, we proposed a fully resource-based method to convert toxic gas H2S and greenhouse gas CO2 synchronously into CO and elemental S by using a novel electrochemical reactor. The special designs include that, in the anodic chamber, H2S was oxidized rapidly to S based on the I−/I3− cyclic redox system to avoid anode passivation. On the other hand, in the cathodic chamber, CO2 was rapidly and selectively reduced to CO based on a porous carbon gas diffusion electrode (GDE) modified with polytetrafluoroethylene and cobalt...
Wave propagation analysis of a spinning porous graphene nanoplatelet-reinforced nanoshell
, Article Waves in Random and Complex Media ; Volume 31, Issue 6 , 2021 , Pages 1655-1681 ; 17455030 (ISSN) ; Mohammadi, K ; Barouti, M. M ; Habibi, M ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
In this article, wave propagation behavior of a size-dependent spinning graphene nanoplatelet-reinforced composite (GNPRC) cylindrical nanoshell with porosity is presented. The effects of small scale are analyzed based on nonlocal strain gradient theory (NSGT), this accurate theory employs exact length scale parameter and nonlocal constant. The governing equations of GNPRC cylindrical nanoshell coupled with piezoelectric actuator (PIAC) are evolved by minimum potential energy principle and solved by the analytical method. For the first time in the current study, wave propagation-porosity behavior of a GNPRC cylindrical nanoshell coupled with PIAC is examined based on NSGT. The results show...