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mortazavi-manesh--a
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Synthesis, characterization and catalytic activity of supported vanadium Schiff base complex as a magnetically recoverable nanocatalyst in epoxidation of alkenes and oxidation of sulfides
, Article Journal of Organometallic Chemistry ; Volume 897 , 2019 , Pages 200-206 ; 0022328X (ISSN) ; Bahjati, M ; Mortazavi Manesh, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
A new magnetically separable nanocatalyst was successfully synthesized by immobilizing of vanadyl acetylacetonate complex, [VO(acac)2], onto silica coated magnetite nanoparticles previously functionalized with 3-aminopropyltriethoxysilane (3-APTES) and reacted by 5-bromosalicylaldehyde to form Schiff base moiety. The obtained nanocatalyst was characterized by elemental analysis (CHN), FT-IR spectroscopy, Powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), inductively coupled plasma optical emission spectrometry (ICP-OES) and thermogravimetric analysis (TGA). Eventually, the resulting nanoparticles were used as catalyst for epoxidation of alkenes and...
Manganese(III) porphyrin anchored onto magnetic nanoparticles via “Click” reaction: An efficient and reusable catalyst for the heterogeneous oxidation of alkenes and sulfides
, Article Inorganic Chemistry Communications ; Volume 107 , 2019 ; 13877003 (ISSN) ; Hosseini, M ; Mortazavi Manesh, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Oxidation of a variety of organic compounds, using Mn-porphyrin, mesotetrakis(4-hydroxyphenyl)porphyrinatomanganese(III), supported onto functionalized silica-coated magnetic nanoparticles via “Click” reaction has been investigated. The heterogeneous catalyst was characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR spectroscopy, inductively coupled plasma optical emission spectroscopy (ICP/OES) and energy-dispersive X-ray spectroscopy (EDX). Thermogravimetric analysis (TGA) demonstrated that the prepared catalyst was thermally stable to almost 300 °C, exhibiting high thermostability of the nanocatalyst over a broad range of temperatures. This...
Synthesis and characterization of molybdenum (VI) complex immobilized on polymeric Schiff base-coated magnetic nanoparticles as an efficient and retrievable nanocatalyst in olefin epoxidation reactions
, Article Applied Organometallic Chemistry ; Volume 34, Issue 3 , 2020 ; Bagherzadeh, M ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
In this study, a new polymeric functionalized magnetic nanocatalyst containing a molybdenum Schiff base complex was prepared using a few consecutive steps. Poly (methylacrylate)-coated magnetic nanoparticles were synthesized via radical polymerization of methyl acrylate onto modified magnetic nanoparticles followed by the amidation of the methyl ester groups with hydrazine. Polymeric functionalization efficiently provides the advantage that more catalytic units can be grafted on the surface of magnetic nanoparticles. The functionalization process was continued with salicylaldehyde which introduced Schiff base groups on to the surface of the polymeric support. In the final step, the desired...
Immobilized Manganese-porphyrin and Molybdenum-Schiff Base Complexes on Functionalized Magnetic Nanoparticles as Efficient Recyclable Nanocatalysts in Hydrocarbon and Sulfide Oxidation Reactions
, Ph.D. Dissertation Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this thesis, functionalized Fe3O4 nanoparticles have been utilized as a support for immobilization of homogeneous catalysts. The catalytic activity of the supported heterogeneous nanocatalysts was investigated in hydrocarbon and sulfide oxidation reactions. In the first part of this research, imidazole functionalized Fe3O4 nanoparticles (Fe3O4@SiO2-Im) were used as a support to anchor manganese porphyrin complex, [MnT(4-OMeP)P]OAc; via axial ligation. Catalytic application of the immobilized manganese porphyrin was studied in oxidation of alkenes and sulfides. To find suitable reaction conditions, the effect of different parameters such as solvent and temperature on immobilization process...
Synthesis of dipyroromethanes in water and investigation of electronic and steric effects in efficiency of olefin epoxidation by sodium periodate catalyzed by manganese tetraaryl and trans disubstituted porphyrin complexes
, Article Journal of Porphyrins and Phthalocyanines ; Volume 23, Issue 6 , 2019 , Pages 671-678 ; 10884246 (ISSN) ; Adineh Jonaghani, M ; Amini, M ; Mortazavi Manesh, A ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2019
Abstract
Condensation of pyrrole with various aldehydes in the presence of BF3•etherate as an acid catalyst in water provides good yield of some dipyrromethanes. Prolongation of the reaction time with aldehydes substituted by electron-donating (mesityl) or electron-withdrawing (2,6-dichlorophenyl) groups on the ortho positions of the phenyl did not lead to decomposition or scrambling. Manganese trans disubstituted porphyrin complexes which derive from various dipyrromethanes and manganese tetraaryl porphyrin complexes including various substituents with different steric and electronic properties show good catalytic activity in epoxidation of alkenes by NaIO4 in the presence of imidazole (ImH). The...
A new model in correlating the activity coefficients of aqueous electrolyte solutions with ion pair formation
, Article Fluid Phase Equilibria ; Volume 261, Issue 1-2 , December , 2007 , Pages 313-319 ; 03783812 (ISSN) ; Taghikhani, V ; Ghotbi, C ; Sharif University of Technology
2007
Abstract
In this work, the Ion Pair Modified Ghotbi-Vera Mean Spherical Approximation (IP-MGV-MSA) model was proposed to correlate the mean ionic activity coefficients (MIAC) for a number of symmetric and asymmetric aqueous electrolyte solutions at 25 °C. The new model is based on the recently proposed MGV-MSA model by Mortazavi-Manesh et al. In the IP-MGV-MSA model, the effects arising from the ion pair formation in the electrolyte solution was taken into account. Also, in the proposed model, while the cation diameter as well as the relative permittivity of water was considered to be dependent on electrolyte concentration, the anion diameter was independent of electrolyte concentration. The results...
Modification of the GV-MSA model in obtaining the activity and osmotic coefficients of aqueous electrolyte solutions
, Article Fluid Phase Equilibria ; Volume 240, Issue 2 , 2006 , Pages 167-172 ; 03783812 (ISSN) ; Taghikhani, V ; Ghotbi, C ; Sharif University of Technology
2006
Abstract
In this work a modified form of the Ghotbi-Vera Mean Spherical Approximation model (MGV-MSA) has been used to correlate the mean ionic activity coefficients (MIAC) for a number of symmetric and asymmetric aqueous electrolyte solutions at 25 °C. In the proposed model the hard sphere as well as the electrostatic contributions to the MIAC and the osmotic coefficient of the previously GV-MSA model has been modified. The results of the proposed model for the MIAC of the electrolyte solutions studied in this work are used to directly calculate the values of the osmotic coefficients without introducing any new adjustable parameter. In the MGV-MSA model the cation diameter as well as the relative...
A new model for predicting activity coefficients in aqueous solutions of amino acids and peptides
, Article Journal of Chemical Thermodynamics ; Volume 35, Issue 1 , 2003 , Pages 101-112 ; 00219614 (ISSN) ; Ghotbi, C ; Taghikhani, V ; Sharif University of Technology
2003
Abstract
A new two-parameter model based on the perturbation of a hard-sphere reference has been developed to correlate the activity coefficients of several amino acids and simple peptides in aqueous solutions. The hard-sphere equation of state used as the reference in the model was proposed recently by Ghotbi and Vera. The perturbation terms coupled with the reference hard-sphere equation of state are attributed to the dispersion forces and the dipole-dipole interactions. The Lennard-Jones and Keesom potential functions are used to represent the dispersion and dipole-dipole interactions, respectively. The results of the new model are compared with those obtained by other models. It is shown that the...
Immobilized manganese porphyrin on functionalized magnetic nanoparticles via axial ligation: Efficient and recyclable nanocatalyst for oxidation reactions
, Article Journal of Coordination Chemistry ; Volume 68, Issue 13 , 2015 , Pages 2347-2360 ; 00958972 (ISSN) ; Mortazavi Manesh, A ; Sharif University of Technology
Taylor and Francis Ltd
2015
Abstract
Magnetic nanoparticles (MNPs), Fe3 O4 @SiO2 , have been prepared and functionalized by 3-(chloropropyl)trimethoxysilane and then by imidazole to synthesize Fe3 O4 @SiO2 -Im. The functionalized Fe3 O4 nanoparticles were used as a support to anchor manganese porphyrin via axial ligation. The prepared catalyst was characterized by elemental analysis, FT-IR spectroscopy, X-ray powder diffraction, UV-vis spectroscopy, and scanning electron microscopy. Application of immobilized manganese porphyrin as a heterogeneous catalyst in oxidation of alkenes and sulfides was explored. To find suitable reaction conditions,...
Nanoparticle supported, magnetically separable manganese porphyrin as an efficient retrievable nanocatalyst in hydrocarbon oxidation reactions
, Article RSC Advances ; Volume 6, Issue 47 , 2016 , Pages 41551-41560 ; 20462069 (ISSN) ; Mortazavi Manesh, A ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
A manganese porphyrin, meso-tetrakis(pentafluorophenyl)porphyrinato manganese(iii) acetate, Mn(TPFPP)OAc, was immobilized on silica-coated magnetic Fe3O4 nanoparticles functionalized with 3-aminopropyltriethoxysilane (APTS) through the amino propyl linkage using a grafting process in toluene solvent. This enabled the covalent immobilization of Mn(iii) porphyrin via an aromatic nucleophilic substitution reaction, to afford the Fe3O4@SiO2-NH2@MnPor catalyst. The resulting nanoparticles were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), FT-IR spectroscopy, UV-Vis spectroscopy, elemental analysis (CHN), atomic absorption spectroscopy (AAS), and vibrating...
The effect of annealing treatment on mechanical properties of aluminum clad steel sheet
, Article Materials and Design ; Volume 24, Issue 8 , 2003 , Pages 617-622 ; 02641275 (ISSN) ; Karimi Taheri, A ; Sharif University of Technology
Elsevier Ltd
2003
Abstract
In this paper, the effects of annealing temperature and time on mechanical properties and bond strength of aluminum clad steel sheet are evaluated. The results indicate that there exist an optimum annealing temperature and time for achieving a suitable formability and bonding strength between the clad layer and base metal. At this annealing time and temperature, the brittle intermetallic layer at the intimate interface of the layers is minimized. © 2003 Elsevier Ltd. All rights reserved
An investigation of deformation behavior and bonding strength of bimetal strip during rolling
, Article Mechanics of Materials ; Volume 37, Issue 5 , 2005 , Pages 531-542 ; 01676636 (ISSN) ; Taheri, A. K ; Sharif University of Technology
2005
Abstract
A mathematical model for cold rolling of two-layer strip is proposed using the upper bound theorem to investigate the plastic deformation behavior of the strip at the roll gap. The effects of total thickness reduction on the rolling power, rolling force, thickness reductions of each layer, and bonding strength of bimetal strip are discussed. Furthermore, experiments on two-layer strip rolling are conducted by employing aluminum-tin alloy and mild steel as the layers of the two-layer strips. It is found that all of theoretical predictions are in good agreement with the experimental measurements. Through the study, it becomes clear that the proposed analytical model is applicable for...
Theoretical and experimental investigation of cold rolling of tri-layer strip
, Article Journal of Materials Processing Technology ; Volume 166, Issue 2 , 2005 , Pages 163-172 ; 09240136 (ISSN) ; Taheri, A. K ; Sharif University of Technology
2005
Abstract
A mathematical model for cold rolling of symmetrical sandwich strip is proposed using the upper bound theorem to investigate the plastic deformation behavior of the strip at the roll gap. The velocity fields derived from the proposed upper bound model can satisfy automatically the volume constancy and the velocity boundary conditions within the roll gap. Effects of various rolling conditions such as the initial thickness and flow stress of each layer in the strip, total thickness reduction and the frictional condition between the strip and roll on the rolling power, rolling force, and thickness reduction of each layer are discussed. Furthermore, experiments on sandwich strip rolling are...
Bond strength and formability of an aluminum-clad steel sheet
, Article Journal of Alloys and Compounds ; Volume 361, Issue 1-2 , 2003 , Pages 138-143 ; 09258388 (ISSN) ; Karimi Taheri, A ; Sharif University of Technology
2003
Abstract
The production of an aluminum-clad steel sheet by the cold rolling process is a more efficient and economical approach compared with the other types of processes utilized for the production of such sheets. In this process, high plastic deformation of two metals, aluminum and steel, is necessary to create the cold bonding between the intermediate surfaces. Therefore, the work-hardened sheet must be annealed in order to obtain a high formability. Heat treatment of the sheet is, however, difficult due to the formation of a brittle intermetallic compound of aluminum and iron at the interface between the layers during heat treatment. In this investigation, the formability of these sheets was...
Study of mechanisms of cold roll welding of aluminium alloy to steel strip
, Article Materials Science and Technology ; Volume 20, Issue 8 , 2004 , Pages 1064-1068 ; 02670836 (ISSN) ; Taheri, A. K ; Sharif University of Technology
Maney Publishing
2004
Abstract
The mechanisms of cold roll welding of aluminium alloy to steel strip has been assessed based on a study of interfacial behaviour at deformations of up to 60% together with the surface characteristics of peeled Al clad steel strip. The proposed mechanisms are applicable where the contact surfaces are degreased and then scratch brushed before the rolling deformation. According to this mechanisms the scratch-brushed layers are fractured shortly after entering the roll gap at a reduction of approximately 10%, which is about the threshold deformation for the roll bonding of aluminium to steel. The transfer cracks formed then become wider so that the distance between each coherent block increases...
Swing up and arm trajectory tracking of the furuta pendulum with sliding mode control
, Article 5th RSI International Conference on Robotics and Mechatronics, IcRoM 2017, 25 October 2017 through 27 October 2017 ; 2018 , Pages 346-351 ; 9781538657034 (ISBN) ; Nikzad Goltapeh, A ; Sharif University of Technology
2018
Abstract
In this paper, the swing-up problem of the Furuta pendulum has been solved by introducing a new combined method based on the frequency response, and the sliding mode method. Furthermore, a trajectory tracking controller has been introduced and applied to the Furuta pendulum; which the pendulum remained regulated at the upward position, while the arm tracks a desired time-varying trajectory. The hierarchical sliding mode control (HSMC) approach has been employed to achieve the mentioned goals. The Furuta system is made up of two subsystems. Based on this physical structure, the hierarchical structure of the sliding surfaces is designed as follows: first, the sliding surface of each subsystem...
FMNV continuous non-malleable encoding scheme is more efficient than believed
, Article 13th International ISC Conference on Information Security and Cryptology, 7 September 2016 through 8 September 2016 ; 2016 , Pages 72-78 ; 9781509039494 (ISBN) ; Salmasizadeh, M ; Daneshgar, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Non-malleable codes are kind of encoding schemes which are resilient to tampering attacks. The main idea behind the non-malleable coding is that the adversary can't be able to obtain any valuable information about the message. Non-malleable codes are used in tamper resilient cryptography and protecting memory against tampering attacks. Several kinds of definitions for the non-malleability exist in the literature. The Continuous non-malleability is aiming to protect messages against the adversary who issues polynomially many tampering queries. The first continuous non-malleable encoding scheme has been proposed by Faust et al. (FMNV) in 2014. In this paper, we propose a new method for proving...
Enhancing water desalination in graphene-based membranes via an oscillating electric field
, Article Desalination ; Volume 495 , December , 2020 ; Moosavi, A ; Nouri Borujerdi, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Water desalination methods on the basis of newly developed graphene-based membrane have been introduced as a more efficient alternative for the conventional water purification technologies such as classical thermal desalination and reverse osmosis (RO). However, the increase of water permeation rate and ion rejection are still the main subjects in this field. In this study, a new method based on using oscillating electric field is proposed to improve the performance of nanoporous graphene. The effects of the amplitude and oscillation frequency of the electric field and the pore size of the membrane on the water permeation and salt rejection are studied by conducting molecular dynamics...
Strong continuous non-malleable encoding schemes with tamper-detection
, Article Information Sciences ; Volume 451-452 , 2018 , Pages 253-270 ; 00200255 (ISSN) ; Salmasizadeh, M ; Daneshgar, A ; Sharif University of Technology
Elsevier Inc
2018
Abstract
A non-malleable encoding scheme is a keyless encoding scheme which is resilient to tampering attacks. Such a scheme is said to be continuously secure if the scheme is resilient to attacks containing more than one tampering procedure. Moreover, such a scheme is said to have the T-tamper-detection property if any kind of tampering attack by an adversary chosen from a predetermined class of algorithms T is detected. Faust et al. have introduced a continuous non-malleable encoding scheme based on non-interactive zero-knowledge (NIZK) which is secure in a strong model for which the adversary receives the tampered codeword as a response to its tampering query if the tampered codeword is not...
Water desalination by charged multilayer graphene membrane: A molecular dynamics simulation
, Article Journal of Molecular Liquids ; Volume 355 , 2022 ; 01677322 (ISSN) ; Moosavi, A ; Nouri Borujerdi, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Graphene, due to its unique excellent properties, is proposed as a developing method with high efficiency compared to classical water desalination methods. In this regard, charging the membrane is considered a promising and effective approach to enhance the performance of the graphene membrane. In this research, by using molecular dynamics simulations, the water desalination by charged multilayer graphene is evaluated and the influence of electric charge amount and geometric parameters, including the pore diameter and the interlayer distance, are investigated. According to the results, the multilayer nanoporous graphene with 16.35 Å pore diameter, in which the electric charge is distributed...