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    Reducing the Size of the Reactor for Production of Fullerene-containing Soot and Study on the Efficiency of Alumina and Silica Gel as Stationary Phase for Separation of C60 and C70

    , M.Sc. Thesis Sharif University of Technology Kadivar Salekoyeh, Mohammad (Author) ; Ghanbari, Bahram (Supervisor) ; Gol Nabi, Hossein (Supervisor)
    In this study, with respect to previous projects, we focused on size reduction of hollow and endohedral fullerenes research reactors. For this reason, we set up two reactors having 1/2 and 3 liters volumes and then such parameters as pressure, reactor temperature, arc duration time, arc time interval and the working electrical current through the electrodes circuit, in both reactors were optimized. The reactors, 3- and 1/2-liter reactors were of types of horizontal and vertical, respectively. In this project spatial angle between two electrodes were also found as effective variable on fullerenes yield in the 3-liters arc reactor for the first time. We found that upon correction of the... 

    Natural frequencies of C60, C70, and C80 fullerenes

    , Article Applied Physics Letters ; Volume 96, Issue 2 , 2010 ; 00036951 (ISSN) Sakhaee Pour, A ; Vafai, A ; Sharif University of Technology
    This letter adopts an atomistic modeling approach to study free vibrational characteristics of C60, C70, and C80 fullerenes. In this regard, we use the molecular structural mechanics consisting of equivalent structural beams to calculate the nonzero natural frequencies. The simulation results indicate that the first natural frequency of the fullerene is in the order terahertz and decreases nonlinearly with respect to the number of the carbon atoms  

    Through-space electronic communication of zinc phthalocyanine with substituted [60]Fullerene bearing O2Nxaza-crown macrocyclic ligands

    , Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 171 , 2017 , Pages 330-339 ; 13861425 (ISSN) Ghanbari, B ; Shahhoseini, L ; Mahlooji, N ; Gholamnezhad, P ; Taheri Rizi, Z ; Sharif University of Technology
    Elsevier B.V  2017
    Two new macrocyclic ligands containing 17- and 19-membered O2N3-donor aza-crowns anchored to [60]Fullerene were synthesized and characterized by employing HPLC, electrospray ionization mass (ESI-MS), 1H and 13C NMR, UV–vis, IR spectroscopies, as well as powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA) in solid state. TGA measurements revealed that upon linking each of these macrocycle rings to [60]Fullerene, the decomposition point measured for [60]Fullerene moiety was increased, indicating on the promoted stability of [60]Fullerene backbone during binding to these macrocyclic ligands. Moreover, the ground state non-covalent interactions of [60]Fullerene derivatives of... 

    Comparative study on the effect of nitrogen-donor groups versus macro-ring size in O2Nx-azacrowns on the complexation with [60]fullerene

    , Article Fullerenes Nanotubes and Carbon Nanostructures ; Vol. 22, issue. 4 , 2014 , pp. 322-331 ; ISSN: 1536383X Ghanbari, B ; Mahloojy, N ; Sharif University of Technology
    The interaction of [60]fullerene with a newly synthesized series of 17-to 21-membered macrocyclic ligands containing an O2N3-donor set has been investigated. The formation constants (K) arising from their complexation with [60]fullerene macrocycles, having various ring size, were measured in CHCl3 media by UV-visible spectroscopy applying Benesi-Hildebrand (BH) equation and their stoichiometries were also determined by the Job method. The best K value was measured for 20-membered ring macrocycle in which a 1:1 complexation stoichiometry with [60]fullerene was dominant. Furthermore, 1H NMR spectroscopy data reveled that the macrocylic ligand coordinates [60]fullerene via the nitrogen-donor... 

    Free vibrations of single walled carbon peapods

    , Article Physica E: Low-Dimensional Systems and Nanostructures ; Vol. 56 , February , 2014 , pp. 410-413 Firouz-Abadi, R. D ; Hojjati, M ; Rahmanian, M ; Sharif University of Technology
    In this paper the free vibration of single walled carbon nanopeapods encapsulating C60 molecules is considered. The nanopeapod is embedded in an elastic medium and clamped at both ends. The Euler-Bernoulli beam model is used for the carbon nanotube and the C60 molecules are considered as lumped masses attached to the beam. Based on the nonlocal elasticity theory the governing equation of motion is derived and the resonance frequencies of the nanopeapod are obtained. The effects of small scale, foundation stiffness and ratio of the fullerenes' mass to the nanotube's mass on the frequencies are studied and some conclusions are drawn  

    A close look at the motion of C60 on gold

    , Article Current Applied Physics ; Volume 15, Issue 11 , November , 2015 , Pages 1402-1411 ; 15671739 (ISSN) Pishkenari, H. N ; Nemati, A ; Meghdari, A ; Sohrabpour, S ; Sharif University of Technology
    Elsevier  2015
    In this paper, we have studied the motion of buckminsterfullerene (C60) on a gold surface by analyzing its potential energy and using classical molecular dynamics method. The results can be employed to investigate the motion of C60-based nanocars which have been made in recent years. For this purpose, we have studied the translational and rotational motions of C60 molecule independently. First, we have calculated the potential energy of a C60 molecule on a gold surface in different orientations and positions and employed this data to predict fullerene motion by examining its potential energy. Then we have simulated the motion of C60 at... 

    Investigation into thermally activated migration of fullerene-based nanocars

    , Article Scientia Iranica ; Volume 25, Issue 3F , 2018 , Pages 1835-1848 ; 10263098 (ISSN) Nemati, A ; Meghdari, A ; Nejat Pishkenari, H ; Sohrabpour, S ; Sharif University of Technology
    Sharif University of Technology  2018
    The rotational and translational motions of nanocars and nanotrucks as well as their motion regimes at different temperatures are investigated. In recent years, few similar types of molecular machines have been simulated. In contrast to previous studies, which have used the Rigid-Body Molecular Dynamics (RBMD) method, an all-atom model and classic atomistic dynamics have been employed in this paper to achieve better accuracy. Our results demonstrated that the exibility of the chassis and its attachment to the gold surface played an important role in the motion of a nanocar. In fact, a heavier and more exible nanocar chassis reduces its speed compared to a nanotruck. In addition, the results... 

    Evaluation of the effects of fullerene c60 nanoparticles on oxidative stress parameters in normal rats liver and brain

    , Article Journal of Advances in Medical and Biomedical Research ; Volume 27, Issue 124 , 2019 , Pages 8-15 ; 26766264 (ISSN) Namadr, F ; Bahrami, F ; Bahri, Z ; Ghanbari, B ; Elahi, S. A ; Mohammadi, M. T ; Sharif University of Technology
    Zanjan University of Medical Sciences and Health Services  2019
    Background & Objective: The potent antioxidant property of fullerene C60 nanoparticles and their derivatives has been demonstrated in a wide range of in vitro and in vivo studies. Hence, we examined the effects of fullerene C60 on the oxidative stress parameters in brain and liver of the rats in normal situation. Materials & Methods: The study was performed in two groups of Wistar rats (each group, n = 6); normal and fullerene-treated normal animals. Treated rats received fullerene via oral gavage at dose of 1 mg/kg/day for 60 days. At termination of the study, the oxidative stress parameters were determined in brain and liver tissues, including the contents of glutathione (GSH) and... 

    Synthesis and Study on Complexation of Naphthalene Azacrown Macrocycle Ligands with [60] Fullerene and Metal Cations Like Cu2+

    , Ph.D. Dissertation Sharif University of Technology Zarepour-jevinani, Morteza (Author) ; Ghanbari, Bahram (Supervisor)
    In the present research, two series of N2O2- and N4O2-naphthadiaza-crown macrocyclic ligands with different macroring size, 15-21 memberd (L1-L7) were synthesized using direct method. The products were characterized by applying 1H and 13C NMR, IR spectroscopy, mass spectrometry and elemental analysis and in some cases by X-ray crystallography. Firstly, to study on emission properties of naphthadiaza-crown macrocyclic ligands as a fluorophore, we employed different amines as fluorescence quencher. It was observed that the quenching effects of 3o aliphatic amines like triethylamine were more pronounce than other group of amines. Also, the quenching constants for interactions of macrocyclic... 

    Study of Tangential Coefficient of Restitution in Nano-particles Collision

    , M.Sc. Thesis Sharif University of Technology Shahbakhti, Abbas (Author) ; Sayyadi, Hasan (Supervisor) ; Nejat, Hosein (Co-Supervisor)
    In this thesis, the collisions of two fluorine-C60 nanoparticles have been studied using molecular dynamics simulation. The main purpose of this thesis is to present a completely new method based on the definition of the vertical and tangential coefficient of restitution, although by using the combination of the simulation and theory results, we can obtain the approximate parameters of physical properties of nanoparticles, such as hardness coefficient, surface tension, friction coefficient, etc.At first, two fluorine C60 under different conditions, including collision velocity, collision angle, initial temperature, initial rotational angle of the molecule, and various potential applications... 

    Synthesis of Aza-Crown Macrocyclic Ligand Appended with Side Arms and Study of their Coordination and Supramolecular Chemistry with Cu2+ and C60

    , M.Sc. Thesis Sharif University of Technology Rezvanifar, Maryam (Author) ; Ghanbari, Bahram (Supervisor)
    In the present study, the coordination chemistry of an O4N4-tetrabenza-crown ether macrocyclic ligand L1 with M2+ (M= Cu, Cd, Hg, and Pb) was investigated by employing UV-visible, 1H-NMR spectroscopy in their solutions. According to the association constants calculated by 1H-NMR titrations, the complex formation stability for these closed shell cations was found in a series of Pb > Hg > Cd, leading to the larger cation, the better accommodation with L1. Moreover, the supramolecular interaction of L1 with fullerene C60 was also assessed by UV-visible spectroscopy. Meanwhile, the structure of [Cd(1)]2+ complex was determine by X-ray crystallographic method in their solid state. A square... 

    Stability of C60-peapods under hydrostatic pressure

    , Article Acta Materialia ; Volume 55, Issue 16 , 2007 , Pages 5483-5488 ; 13596454 (ISSN) Najafi Sohi, A ; Naghdabadi, R ; Sharif University of Technology
    The stability of single-walled carbon nanopeapods under hydrostatic pressure is investigated using a continuum-based elastic shell model. The model incorporates nonbonded van der Waals interactions between the nested fullerenes and the host carbon nanotube. By deriving an explicit equation, it is shown that the critical hydrostatic pressure for the onset of structural instability of a completely packed C60@(10,10) nanopeapod is ∼1.11 GPa, while for the case of the pristine host (10,10) nanotube it is ∼1.84 GPa. Thus, it is concluded that the fullerene encapsulation weakens the host nanotube under hydrostatic pressure. In addition, it is quantitatively shown that any decrease in packing... 

    Torsional buckling of carbon nanopeapods

    , Article Carbon ; Volume 45, Issue 5 , 2007 , Pages 952-957 ; 00086223 (ISSN) Najafi Sohi, A ; Naghdabadi, R ; Sharif University of Technology
    Torsional buckling of carbon nanopeapods (carbon nanotubes filled with fullerenes) is studied using a continuum-based multi-layered shell model. The model takes into account non-bonded van der Waals interactions between nested fullerenes and the innermost layer of host nanotube. For nanopeapods with linearly arranged nested fullerenes, equivalent pressure distribution is proposed to model these interactions. Deriving explicit equations governing the torsional stability, it is concluded that the critical torsional load of a carbon nanopeapod is less than that of a carbon nanotube under otherwise identical geometric and mechanical conditions. Performing numerical calculations, it is also shown... 

    Thermodynamic study on the effect of O 2N 2-azacrown macrocyclic ring-size in complexation with [60]fullerene

    , Article Fullerenes Nanotubes and Carbon Nanostructures ; Volume 21, Issue 5 , Oct , 2013 , Pages 394-402 ; 1536383X (ISSN) Ghanbari, B ; Aratboni, A. M ; Sharif University of Technology
    The interaction of [60]fullerene with a series of 15-19-membered macrocycles containing an O 2N 2-donor set has been investigated by UV-visible spectroscopy. The formation constants arising from the complexation of [60]fullerene with these azacrown macrocycles, having various ring size, were determined in CHCl 3 media applying Benesi-Hildebrand equation. The stoichiometry has been found by the Job method in each case. The thermodynamic parameters, for example, formation enthalpies (δH o) and entropies (δS o), for these complexation were also determined. Experimentally, it was found that macroring size of the azacrown has a prominent effect on azacrown complexation with [60]fullerene in terms... 

    Gold nanoparticles functionalized with fullerene derivative as an effective interface layer for improving the efficiency and stability of planar perovskite solar cells

    , Article Advanced Materials Interfaces ; Volume 7, Issue 21 , 2020 Chavan, R. D ; Prochowicz, D ; Bończak, B ; Tavakoli, M. M ; Yadav, P ; Fiałkowski, M ; Hong, C. K ; Sharif University of Technology
    Wiley-VCH Verlag  2020
    Titanium dioxide (TiO2) is an extensively used electron transporting layer (ETL) in n–i–p perovskite solar cells (PSCs). Although, TiO2 ETL experiences the high surface defect together with low electron extraction ability, which causes severe energy loss and poor stability in the PSC. In this study, a new intermediate layer consisting of gold nanoparticles functionalized with fully conjugated fullerene C60 derivative (C60-BCT@Au NPs) that enhances the interfacial contact at ETL/perovskite interface leading to a perovskite film with improved crystallinity and morphology is reported. Moreover, the studies demonstrate that the interface modification of the TiO2 ETL with C60-BCT@Au NPs... 

    Investigation on the Solfate and Chloride ion Concentration on Carbon Nanotubes Frmation Via Arc Discharge in Aqueous Solution

    , M.Sc. Thesis Sharif University of Technology Shervin, Shahab (Author) ; Simchi, Abdolreza (Supervisor) ; Khomamizade, Farzad (Supervisor)
    In this work, carbon nanotubes (CNTs) were synthesized via arc discharge in an aqueous solution. The role of iron catalyst in CNTs formation was investigated utilizing arc discharge in iron salts solution (Fe2(SO4)3 and FeCl3). Thermogarvimetric (TG) analysis showed the presence of multi-layered structures including multi-walled carbon nanotubes (MWCNTs) and multi-shelled graphite particles when processing was performed in DI-water. In the presence of iron ions, single-walled carbon nanotubes (SWCNTs) and double-walled carbon nanotubes (DWCNTs) were formed. The effect of iron ions (Fe3+) concentration on CNTs yield was investigated by Raman spectroscopy. The highest yield was obtained when... 

    Design and Analysis of Nano Ball Bearing

    , M.Sc. Thesis Sharif University of Technology Naseiri Sarvi, Masuod (Author) ; Ahmadian, Mohammad Taghi (Supervisor)
    Nowadays, science of nano technology has been growing quickly in the past decade. Scientists implemented this technology in bioengineering, electronics and medicine extensively. Nano scale engineering is one of the interests of researchers, nano bearing as a nano scale structure and as an important part of nano machining plays an important role in micro and nano devices. The role of nano bearing is to decrease energy dissipation and increase the efficiency of nano machines. The main purpose of this study is to design and analyze an optimized nano ball bearing. In this regard, a new spherical super element is designed and presented. This super element is implemented in simulating the... 

    (Synthesis and Comparative Study on Complexation of OxNy-Azacrown Macrocyclic Ligands with [60] Fullerene and Cu(II

    , M.Sc. Thesis Sharif University of Technology Varmazyad, Mahboubeh (Author) ; Ghanbari, Bahram (Supervisor)
    In our previous work in this laboratory, macrocycle containingO_2 N_2 and O_2 N_3- donor set with various ring size were synthesized. The intraction of macrocyles with [60]fullerene were determined. In this research, we synthesized 22-membered aza-crown macrocycle ligand containing O_4 N_2- donor set and characterized by NMRspectroscopy. The intraction of macrocycle with [60]fullerene were also investigated by UV-Visible spectroscopy. The formation constant was determined applying Benesi--Hildebrand equation. The result has been showed that O_4 N_2 macrocyle had better complexation with [60]fullerene in comparision of O_2 N_3 and O_2 N_2 donor sets. Then, the interaction of O_4 N_2 with... 

    Study on Cation and Fullerene Recognition by OxNx-Aza Crown Macrocyclic Ligands

    , M.Sc. Thesis Sharif University of Technology Safar koopayeh, Barzin (Author) ; Ghanbari, Bahram (Supervisor)
    In this research, a new group of N2O2–azacrown macrocyclic ligands with different macroring size from 15 to 18 was synthesized using one-pot facile and high yield reaction. The products were characterized applying FT-IR, 1H and 13C NMR spectroscopies as well as elemental analysis. The single crystal structure of 18-membered macrocyclic ligand was also determined by x-ray crystallography. The crystallographic data showed such strong inter-molecular hydrogen bonding which excluded their nitrogen-donor groups, and initial investigation with UV-Vis spectroscopy shows no intraction with [60]fullerene, despite of presence of these interacrtions in their parent macrocycles. The result of Job’s... 

    Synthesis of Tweezer-Like OxNy Macrocyclic Ligands and Study on the Effect of Macroring Linking on Selectivity Towards [60]Fullerene and Transition Metal Cations

    , Ph.D. Dissertation Sharif University of Technology Gholamnezhad, Parisa (Author) ; Ghanbari, Bahram (Supervisor) ; Bagherzadeh, Mojtaba (Co-Advisor)
    By considering previous works undertaken in our laboratory on the interaction between O2N2 azacrown and [60]fullerene using UV-vis spectroscopy. It was found that the significant interaction occurs in less than one hour. Extending this time in this research, the reaction between [60]fullerene with 15 to 19 membered N2O2-azacrown macrocyclic ligands was investigated during ten days. The new compounds L1, L2 were synthesized and characterized applying HPLC, ESI-Mass, TG, DSC, IR as well as elemental analysis. The interaction of new compounds with Cu(II) and Ni(II) and Co(II) using UV-vis spectroscopy showed that L2 gave the highest Kb value of cations/(L1, L2). Besides, it was found that the...