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mahdavian--mohammad
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A Survey on the Effect of Travel Mode Choice on Citizens’ Subjective Wellbeing
, M.Sc. Thesis Sharif University of Technology ; Kermanshah, Mohammad (Supervisor)
Abstract
Different definitions of the term ‘subjective well-being’ have been defined by different researchers. While there is no definite definition for this concept, it can be related to one's life evaluation. The issue of citizens’ subjective well-being has not usually been considered in transportation policies, such as reducing single occupancy vehicle. However, subjective well-being reflects the individuals’ quality of life and can be one of the main priorities of any society. This study tries to find the effect of using various modes of travel including passenger car, motorcycle, public transportation and walking on citizens' subjective well-being. Subjective well-being is measured by...
Modified WK-Recursive Topology for an Optical Network-on-Chip
, M.Sc. Thesis Sharif University of Technology ; Hesabi, Shahin (Supervisor)
Abstract
Nowadays, a large proportion of the power consumption in high-performance multi-processor architectures on chip belongs to connections. Reducing power consumption while maintaining high efficiency in these architectures is one of the main concerns. Networks on Chip (NoC) originally were introduced to improve efficiency, but now, given the importance of power, we must provide some solutions to reduce power consumption, and delay in NOCs. Connections in chip can be divided into three categories: global, intermediate and local, while the length of global connections is almost constant in different scales, local connections are scalable. As a result improving efficiency of a small number of...
Synthesis and Comparative Study on Complex Formation of Azo-bearing Nitrogen-Donor Macrocyclic Ligands with Fullerene C60 and Cu(II) Cation
, Ph.D. Dissertation Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In the present research, a series of bimacrocyclic tweezer anchored through azobenzene moiety were synthesized and characterized by applying IR spectroscopy, 1H and 13C{1H} NMR, fluorescence spectroscopy, UV-visible spectroscopy, mass spectrometry and elemental analysis and in some cases by X-ray crystallography. Firstly, UV-visible spectroscopy established that the irradiation of the tweezers with UV light promoted the trans to cis isomerization. On the other hand, thermal cis-trans isomerization behavior of the azobenzene moiety in tweezers was surveyed in which the cis isomers were formed of the heating at 50 oC for 5 minutes. Where the -OH group was replaced with 4-toluenesulfonyl...
Probing the Performance of Safflower Plant as a Green Inhibitor with Molybdenum Disulfide on Corrosion Protection Properties of the Epoxy Coating
, M.Sc. Thesis Sharif University of Technology ; Ramazani Saadat Abadi, Ahmad (Supervisor) ; Mahdavian Ahadi, Mohammad (Supervisor)
Abstract
Today, the process of corrosion and compensation of minor injuries, without the need for tracing or any other physical interference, has become one of the subjects of interest to researchers. Inhibitors have been considered as one of the anti-corrosion agents. In this research, safflower extract as a green inhibitor in sodium chloride corrosive environment was used to evaluate the rate of corrosion of mild steel. Also the MoS2 nanoparticles were used as carrier of this green inhibitore in the epoxy coating to allow the activation of the coating in a scratched state in sodium chloride solution of 3.5%. In the first step, the extract of the safflower was prepared to reach the best part of this...
Fabrication and Evaluation of Mechanical and Anti-corrosion Properties of Epoxy Resin/Carbon Nanofibers Containing Organic Corrosion Inhibitors
, M.Sc. Thesis Sharif University of Technology ; Ramazani Saadat Abadi, Ahmad (Supervisor) ; Mahdavian Ahadi, Mohammad (Supervisor)
Abstract
To protect mild steel against corrosion, an intelligent self-healing epoxy (EP) coating including carbon nanofiber (CNF) modified with polydopamine (PDA)-La (III) complex was successfully fabricated. The high aspect ratio and unique thermal and electrical characteristics of CNF made it an ideal physical barrier against the penetration of corrosive ions. Due to the poor dispersion of CNF, its surface was modified using PDA. PDA, which contains functional groups such as catechol, amine, and imine, can mitigate corrosion reaction by generating the Fe-Catechol complex and also boost the coating's adherence to the metal surface, in addition to anchoring La3+ inorganic corrosion inhibitor....
The effect of sol-gel surface modified silver nanoparticles on the protective properties of the epoxy coating
, Article RSC Advances ; Volume 6, Issue 23 , 2016 , Pages 18996-19006 ; 20462069 (ISSN) ; Haddadi, S. A ; Mahdavian, M ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
In this study, the effect of surface modified silver nanoparticles on the corrosion protection of an epoxy coating on mild steel was studied. An organosilane (3-methoxy silyl propyl metacrylate) was used as a surface modifier to increase the dispersability of the inorganic nanoparticles in the organic epoxy coating matrix. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to characterize the surface modified nanoparticles. Differential scanning colorimetry (DSC) was employed to study the effects of modified and unmodified nano-silver on the curing heat and glass transition temperature of the epoxy coatings. Salt spray and electrochemical impedance...
Synthesis and Application of Carbon Hollow Nanospheres Containing Active Film Forming Agents for Fabrication of Self-Healing Epoxy Resin
, Ph.D. Dissertation Sharif University of Technology ; Ramazani, Ahmad (Supervisor) ; Mahdavian, Mohammad (Supervisor) ; Taheri, Peyman (Co-Supervisor) ; Mol, Arian (Co-Supervisor)
Abstract
Nowadays, self-healing process, repairing minor damages automatically without the need for detection or any type of manual intervention, becomes a hot topic of general interest. In this research, the effect of addition of carbon nanocontainers doped with film forming epoxy and polyamine agents in various contents on the self-healing properties of epoxy resin was investigated. Carbon nanocontainers were synthesized via the silica templating method and carbonization of polysaccharide shells at the high temperature. Loading of the film forming agents into carbon nanocontainers was performed using vacuum jar method in the presence of epoxy/acetone and polyamine/acetone dilute solutions....
Hybrid particle swarm-based-simulated annealing optimization techniques
, Article IECON 2006 - 32nd Annual Conference on IEEE Industrial Electronics, Paris, 6 November 2006 through 10 November 2006 ; 2006 , Pages 644-648 ; 1424401364 (ISBN); 9781424401369 (ISBN) ; Zamani, M ; Feyz Mahdavian, H. R ; Sharif University of Technology
2006
Abstract
Particle Swarm Optimization (PSO) algorithms recently invented as intelligent optimizers with several highly desirable attributes. In this paper, two new hybrid Particle Swam Optimization schemes are proposed. The proposed hybrid algorithms are based on using the Particle Swarm Optimization techniques in conjunction with the Simulated Annealing (SA) approach. By simulating three different test functions, it is shown how the proposed hybrid algorithms offer the capability of converging toward the global minimum or maximum points. More importantly, the simulation results indicate that the proposed hybrid particle swarm-based simulated annealing approaches have much superior convergence...
Robust multiple model adaptive control using fuzzy fusion
, Article 2010 42nd Southeastern Symposium on System Theory, SSST 2010, Tyler, TX, 7 March 2010 through 9 March 2010 ; March , 2010 , Pages 19-24 ; 9781424456901 (ISBN) ; Dumont, G. A ; Feyz Mahdavian, H. R ; Sharif University of Technology
2010
Abstract
A robust multiple model adaptive control strategy using fuzzy fusion (RMMAC-FF) is presented in this paper. The main idea in multi-model controllers is to identify the best model of the system at any instant of time and apply the appropriate control input to it. RMMAC-FF, integrates a fuzzy robust controller, with the fuzzy multiple model adaptive estimation and a fuzzy switching to come up with a new strong methodology to control complex systems. Simulation results of the RMMAC-FF on a two-cart system, used as a benchmark problem, verify the theory and confirm the effectiveness of the proposed controller
Adsorption of eco-friendly carthamus tinctorius on steel surface in saline solution: a combination of electrochemical and theoretical studies
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 601 , 20 September , 2020 ; Ramazani Saadat Abadi,A ; Mahdavian, M ; Bahlakeh, G ; Haddadi, S. A
Elsevier B.V
2020
Abstract
In this study, the different parts of carthamus tinctorius plant, including petal (SPE), leaf (SLE), and shoot (SSE), have been extracted. Adsorption of the extracts on mild steel in 3.5 wt. % NaCl solution was evaluated employing electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, and electrochemical noise measurements (EN). The field-emission scanning electron microscopy (FE-SEM) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) were employed to appraise the morphology of the samples surface subjected to the test solutions. According to the EIS results, the maximum adsorption efficiency belonged to the solution containing 1 g L−1 of...
Development of an active/barrier bi-functional anti-corrosion system based on the epoxy nanocomposite loaded with highly-coordinated functionalized zirconium-based nanoporous metal-organic framework (Zr-MOF)
, Article Chemical Engineering Journal ; 2020 ; Ramezanzadeh, B ; Bahlakeh, G ; Tati, A ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
For the first time, the UIO-66, NH2-UIO, and NH2-UIO particles covalently functionalized by Glycidyl Methacrylate (GMA@NH2-UIO), were utilized as the novel functional anti-corrosive fillers. The functionality, high surface area, phase composition, excellent thermal properties as well as chemical stability of the Zr-MOFs were proved by FT-IR, BET, XRD, TGA, and water stability tests, respectively. The smart pH-sensitive controlled-release activity of the corrosion inhibitors (i.e., Zr ions and organic compounds) from the prepared Zr-MOFs was proved by the water stability test of the Zr-MOFs particles in the acidic (pH = 2), neutral (pH = 7.5), and alkaline (pH = 12) solutions containing 3.5...
Epoxy nanocomposite coatings with enhanced dual active/barrier behavior containing graphene-based carbon hollow spheres as corrosion inhibitor nanoreservoirs
, Article Corrosion Science ; Volume 185 , 2021 ; 0010938X (ISSN) ; Ramazani Saadatabadi, A ; Mahdavian, M ; Arjmand, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Graphene-based carbon hollow spheres (CHSs) fabrication, doped with 2-mercaptobenzimidazole (MBI) was successfully done in previous work. The active/barrier corrosion protection performance (CPP) of epoxy coatings was evaluated using salt spray test, electrochemical impedance spectroscopy (EIS), and scanning vibrating electrode technique (SVET). Results proved the active/barrier CPP enhancement of epoxy coatings in the presence of 3 wt. % MBI@CHSs. While the presence of MBI and empty CHSs in epoxy coatings did not further improve the active performance. An improvement in the adhesion loss of the epoxy coating, ca. 58 %, was observed in the presence of 3 wt. % MBI@CHSs. © 2021
Development of an active/barrier bi-functional anti-corrosion system based on the epoxy nanocomposite loaded with highly-coordinated functionalized zirconium-based nanoporous metal-organic framework (Zr-MOF)
, Article Chemical Engineering Journal ; Volume 408 , 2021 ; 13858947 (ISSN) ; Ramezanzadeh, B ; Bahlakeh, G ; Tati, A ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
For the first time, the UIO-66, NH2-UIO, and NH2-UIO particles covalently functionalized by Glycidyl Methacrylate (GMA@NH2-UIO), were utilized as the novel functional anti-corrosive fillers. The functionality, high surface area, phase composition, excellent thermal properties as well as chemical stability of the Zr-MOFs were proved by FT-IR, BET, XRD, TGA, and water stability tests, respectively. The smart pH-sensitive controlled-release activity of the corrosion inhibitors (i.e., Zr ions and organic compounds) from the prepared Zr-MOFs was proved by the water stability test of the Zr-MOFs particles in the acidic (pH = 2), neutral (pH = 7.5), and alkaline (pH = 12) solutions containing 3.5...
PO43--Loaded zif-8-type metal-organic framework-decorated multiwalled carbon nanotube synthesis and application in silane coatings for achieving a smart corrosion protection performance
, Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 32 , 2022 , Pages 11747-11765 ; 08885885 (ISSN) ; Ramezanzadeh, M ; Fedel, M ; Ramezanzadeh, B ; Mahdavian, M ; Sharif University of Technology
American Chemical Society
2022
Abstract
In this research study, interfacial assembled nanoporous zeolitic imidazolate framework (ZIF-8) multiwalled oxidized carbon nanotubes (MW-OCNTs) were developed and introduced into a silane coating. To analyze the destructive behavior of the nanoparticles exposed to salty solutions with three distinctive pHs of 2, 7.5, and 12, various types of tests such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and inductively coupled plasma (ICP) were accomplished. The XRD test revealed that the main characteristic peaks of ZIF-8 were eliminated and/or their intensity decreased. In accordance with the obtained data from the XRD test, nanoparticles at pH = 2 had been...
PH-Sensitive polydopamine–La (III) complex decorated on carbon nanofiber toward on-demand release functioning of epoxy anti-corrosion coating
, Article Langmuir ; Volume 38, Issue 38 , 2022 , Pages 11707-11723 ; 07437463 (ISSN) ; Saadatabadi, A. R ; Mahdavian, M ; Haddadi, S. A ; Sharif University of Technology
American Chemical Society
2022
Abstract
The high aspect ratio and unique thermal and electrical characteristics of carbon nanofiber (CNF) made it an ideal physical barrier against the penetration of corrosive ions. However, the poor compatibility of the CNF with the polymer matrix and the lack of active corrosion inhibitors are the key limitations of this nanomaterial, resulting in short-term anti-corrosion resistance. An intelligent self-healing epoxy (EP) coating, including CNF modified with a polydopamine (PDA)-La3+ complex, was successfully fabricated to overcome these issues. Electrochemical impedance spectroscopy (EIS) evaluation implied that mild steel (MS) submerged in a 3.5 wt % NaCl solution containing the CNF-PDA-La...
A detailed atomic level computational and electrochemical exploration of the Juglans regia green fruit shell extract as a sustainable and highly efficient green corrosion inhibitor for mild steel in 3.5 wt% NaCl solution
, Article Journal of Molecular Liquids ; Volume 284 , 2019 , Pages 682-699 ; 01677322 (ISSN) ; Alibakhshi, E ; Bahlakeh, G ; Ramezanzadeh, B ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Seawater, which has been frequently applied in cooling and injection water systems, imposes severe pitting corrosion to mild steel. Addition of green and sustainable inhibitors based on renewable sources is one of the promising methodologies for restricting metal corrosion in chloride-containing electrolytes. In this study, for the first time, from both theoretical and experimental faces, the role of Juglans regia green fruit shell (JRS) extract as a sustainable potent corrosion inhibitor for mild steel was studied. The chemical structure of the JRS extract was deliberated by Fourier transform infrared spectroscopy (FT-IR). By electrochemical techniques including polarization, EIS and...
Persian Liquorice extract as a highly efficient sustainable corrosion inhibitor for mild steel in sodium chloride solution
, Article Journal of Cleaner Production ; Volume 210 , 2019 , Pages 660-672 ; 09596526 (ISSN) ; Ramezanzadeh, M ; Haddadi, S. A ; Bahlakeh, G ; Ramezanzadeh, B ; Mahdavian, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The Persian Liquorice was introduced as a sustainable corrosion inhibitor with excellent inhibition action for mild steel in sodium chloride solution. Persian Liquorice is a root of Glycyrrhiza glabra including many active compounds like Glycyrrhizin (GL), 18β- Glycyrrhetinic acid (GA), Liquritigenin (LTG), Licochalcone A (LCA), Licochalcone E (LCE), and Glabridin (GLD). The Fourier transform infrared (FT-IR) spectroscopy was utilized to track various active components exist in the Persian Liquorice extract. Electrochemical impedance spectroscopy, potentiodynamic polarization and electrochemical current noise measurements were conducted to investigate the corrosion inhibition role of various...
Synthesis and application of mesoporous carbon nanospheres containing walnut extract for fabrication of active protective epoxy coatings
, Article Progress in Organic Coatings ; Volume 133 , 2019 , Pages 206-219 ; 03009440 (ISSN) ; Behroozi Kohlan, T ; Momeni, S ; Ramazani S. A., A ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this article, the synthesis procedure of mesoporous carbon nanospheres (MCNSs) using silica hard-templates, doping of the nanospheres with walnut extract, and their impact on active protective properties of an epoxy coating are presented. Field emission scanning electron microscope (FE-SEM) results showed that the synthesis of these nanocontainers was successfully done in spherical form. Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR) results showed that walnut extract as a green inhibitor was doped into the pores of nanocapsules. Corrosion resistance of the mild steel samples in the 3.5 wt.% NaCl solution in the presence and absence of walnut extract...
Mechanical and corrosion protection properties of a smart composite epoxy coating with dual-encapsulated epoxy/polyamine in carbon nanospheres
, Article Industrial and Engineering Chemistry Research ; Volume 58, Issue 8 , 2019 , Pages 3033-3046 ; 08885885 (ISSN) ; Ramazani, S. A ; Mahdavian, M ; Taheri, P ; Mol, J. M. C ; Sharif University of Technology
American Chemical Society
2019
Abstract
Carbon nanocapsules doped separately with epoxy and polyamine were used to fabricate an epoxy nanocomposite coating. Carbon nanospheres with dual-encapsulated epoxy/polyamine were dispersed uniformly in the epoxy resin at concentrations of 2, 5, and 10 wt %. The mechanical properties of the nanocomposites were studied by tensile testing and scratch hardness measurements. Furthermore, nanocomposites were applied on mild steel substrates, and their corrosion protection and barrier performance were evaluated using electrochemical impedance spectroscopy (EIS). Adhesion loss measurements of coatings after 240 h exposure to 3.5 wt % NaCl solution were performed by pull-off adhesion testing. Also,...
Corrosion inhibition of a novel antihistamine-based compound for mild steel in hydrochloric acid solution: experimental and computational studies
, Article Scientific Reports ; Volume 12, Issue 1 , 2022 ; 20452322 (ISSN) ; Ahmad Ramazani, S. A ; Kordzadeh, A ; Mahdavian, M ; Alibakhshi, E ; Ghaderi, A ; Sharif University of Technology
Nature Research
2022
Abstract
Focused on the assessment of the diphenhydramine hydrochloride (DPH) capabilities as an alternative to conventional and harmful industrial corrosion inhibitors, electrochemical techniques were employed. The optimum concentration of 1000 ppm was determined by molecular simulation and validated through electrochemical experiments. The results acquired from the electrochemical impedance spectroscopy (EIS) study showed that DPH at a concentration of 1000 ppm has a corrosion efficiency of 91.43% after 6 h immersion. The DPH molecules' orientation on the surface was assessed based on EIS predicting horizontal adsorption on the surface. Molecular simulations were done to explore the adsorption...