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    A new approach for the in vitro identification of the cytotoxicity of superparamagnetic iron oxide nanoparticles

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 75, Issue 1 , 1 January , 2010 , Pages 300–309 Mahmoudi, M. (Morteza) ; Simchi, A. (Abdolreza) ; Imani, M. (Mohammad) ; Shokrgozar, M. A. (Mohammad A.) ; Milani, A. S. (Abbas S.) ; Hafeli, Urs O ; Stroeve, Pieter ; Sharif University of Technology
    Superparamagnetic iron oxide nanoparticles (SPIONs) are increasingly used in medical applications, such as targeting delivery and imaging. In the future, patients are more likely to be exposed to pharmaceutical products containing such particles. The study of toxicity of SPIONs has become of great importance in recent years, although the published data in this arena is limited. The aim of the present work is to investigate the cytotoxicity of SPIONs and the effect of the particles on the cell medium components. For this purpose, uncoated and polyvinyl alcohol (PVA) coated SPIONs with narrow size distribution were synthesized via a well-known coprecipitation method. The mouse fibroblast cell... 

    Fabrication of gas ionization sensor based on titanium oxide nanotube arrays

    , Article Applied Physics A ; Volume 115, Issue 4 , June , 2014 , pp 1387-1393 ; 1432-0630 Nikfarjam, A. (Alireza) ; Mohammadpour, R. (Raheleh) ; Iraji Zad, A. (Azam) ; Sharif University of Technology
    Gas sensors have been fabricated based on field ionization from titanium oxide nanotubes grown on titanium foil. Ordered nanaotube arrays of titanium oxides were grown by the anodization method. We measured breakdown voltages and discharge currents of the device for various gases. Our gas ionization sensors (GIS) presented good sensitivity, selectivity, and short response time. The GISs based on TiO2 nanotube arrays showed lower breakdown voltage, higher discharge current, and good selectivity. An excellent response observed for Ar compared to other gases. Besides, by introducing 2 % CO and 4 % H2 to N2 flow gas, the amount of breakdown voltage shifts about 20 and 70 volts to the lower... 

    H2S sensing properties of added copper oxide in WO3

    , Article Key Engineering Materials ; Volume 543 , March , 2013 , Pages 145-149 Nowrouzi, R. (Rasoul) ; Razi Astaraei, F. (Fatemeh) ; Kashani, Sh. (shima) ; Iraji Zad, A. (Azam) ; Sharif University of Technology
    We study Hydrogen sulfide gas detection properties of pure and 1% copper oxide added WO3 thin films. The spin coated deposits on alumina substrates were annealed at 500 C for 1 hour in order to improve the crystallinity of the films. The sensitivity of pure tungsten oxide is poor even at temperatures of about 100 C but the doped samples exhibit good response to H2S gas. Our data show sensitivity of about 1500 in 10 ppm diluted gas in air at 100 C. The films are sensitive to the gas even at 250 ppb (sensitivity about 2) H2S concentration at 100 C but with rather long recovery time. Crystal structure, morphology and chemical composition of samples were studied by X-Ray diffraction (XRD),... 

    Molybdenum(VI)-oxodiperoxo complex containing an oxazine ligand: Synthesis, X-ray studies, and catalytic activity

    , Article Journal of Coordination Chemistry ; Vol. 67, issue. 8 , Jul , 2014 , pp. 1429-1436 ; ISSN: 00958972 Amini, M ; Bagherzadeh, M ; Atabaki, B ; Derakhshandeh, P. G ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    A new mononuclear molybdenum(VI)-oxodiperoxo complex [MoO(O 2)2(phox)] with a simple bidentate ligand, 2-(2′-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (Hphox), has been synthesized and characterized by X-ray structure analysis, elemental analysis, infrared, and 1H NMR spectroscopy. A triclinic space group P-1 was determined by X-ray crystallography from single-crystal data of this complex. The resulting complex functioned as a facile sulfide oxidation catalyst with urea hydrogen peroxide as terminal oxidant at room temperature. The catalyst showed efficient reactivity in oxidation of sulfides giving high yield and selectivity  

    A water-oxidizing dinuclear iron complex as an efficient catalyst toward organic sulfide oxidation

    , Article Journal of Coordination Chemistry ; Vol. 67, issue. 18 , Jul , 2014 , p. 3026-3032 Amini, M ; Najafpour, M. M ; Zare, M ; Holynska, M ; Moghaddam, A. N ; Bagherzadeh, M ; Sharif University of Technology
    In this paper, we report that a known dinuclear Fe complex, [tpa(H2O)FeOFe(H2O)tpa](ClO4)4 (tpa: tris(2-pyridylmethyl)amine), is an efficient catalyst toward organic sulfide oxidation in the presence of urea-hydrogen peroxide  

    Synthesis, characterization, and catalysis of recyclable new piperazine-bridged Mo(VI) polymers [MoO 2(Salen)(piperazine)] n in highly selective oxygenation of alkenes and sulfides

    , Article Journal of Coordination Chemistry ; Volume 66, Issue 16 , 2013 , Pages 2885-2900 ; 00958972 (ISSN) Bagherzadeh, M ; Zare, M ; Sharif University of Technology
    This study reports synthesis and characterization of polymeric [MoO2(Salen)] complexes that combine MoO2(acac)2 and polymeric ligands bearing N2O2 coordination sites, abbreviated herein as [piperazinCH2{MoO2(Salen)}]n (6), [piperazinCH2{MoO2(Salophen)}]n (7), and [piperazinCH2{MoO2(Salpn)}]n (8). The epoxidation of alkenes using tert-butyl hydroperoxide and oxidation of sulfides to sulfoxides by urea hydrogen peroxide were enhanced with excellent selectivity under the catalytic influence of these coordination polymers. No relevant difference in activity was found due to change in the diamine in the Schiffs base ligands. The stability of polymeric catalysts was assessed by recycling a sample... 

    Oxido-peroxido molybdenum(VI) complexes in catalytic and stoichiometric oxidations

    , Article Coordination Chemistry Reviews ; Volume 257, Issue 7-8 , April , 2013 , Pages 1093-1121 ; 00108545 (ISSN) Amini, M ; Haghdoost, M. M ; Bagherzadeh, M ; Sharif University of Technology
    This review mainly discusses the application of oxido-peroxido Molybdenum(VI) complexes as catalysts or mediators in homogeneous or heterogeneous catalytic systems for oxidations of olefins, sulfides, alcohols, alkanes, and amines toward the synthesis of a variety of organic compounds, such as epoxides, sulfoxides, aldehydes and ketones, carboxylic acids, alcohols and nitroso compounds  

    Catalytic efficiency of a novel complex of oxoperoxo molybdenum(VI): Synthesis, X-ray structure and alkane oxidation

    , Article Inorganic Chemistry Communications ; Volume 15 , January , 2012 , Pages 52-55 ; 13877003 (ISSN) Bagherzadeh, M ; Amini, M ; Ellern, A ; Woo, L. K ; Sharif University of Technology
    A new mononuclear oxo-peroxo complex of molybdenum(VI) of the formula [MoO(O2)(phox)2] (where phox = 2-(2′-hydroxyphenyl) oxazoline) has been synthesized and characterized by X-ray structure analysis, elemental analysis, infrared, UV-visible and 1H, 13C NMR spectroscopy. A monoclinic space group P-1 was determined by X-ray crystallography from single-crystal data of this complex. Complex functions as facile alkane oxidation catalyst with hydrogen peroxide as terminal oxidant at room temperature. The catalyst shows very much efficient reactivity in the oxidation reactions giving high yield, turnover number (TON) and selectivity  

    A novel efficient magnetic core-zeolitic shell nanocatalyst system: Preparation, characterization and activity

    , Article Chemical Papers ; Volume 69, Issue 6 , 2015 , Pages 856-863 ; 03666352 (ISSN) Padervand, M ; Vossoughi, M ; Janfada, B ; Sharif University of Technology
    De Gruyter Open Ltd  2015
    Analcime shell-nickel ferrite core microspheres were decorated with Pd and Pt nanoparticles with the aid of an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6). The samples thus prepared were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), nitrogen adsorption-desorption isotherms, transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) methods. The XRD patterns confirmed the growth of a zeolitic layer on the surface of the magnetic cores. The thermogravimetric analysis (TGA) curve clearly indicated the thermal decomposition of the loaded IL, which confirmed the presence of... 

    Consequence analysis of different ethylene oxide dispersion scenarios from storage tanks in an Iranian petrochemical complex

    , Article 19th International Congress of Chemical and Process Engineering, CHISA 2010 and 7th European Congress of Chemical Engineering, ECCE-7, 28 August 2010 through 1 September 2010, Prague ; 2010 Abdolhamidzadeh, B ; Honarvar, B ; Rashtchian, D ; Sharif University of Technology
    Ethylene oxide production units are among the most dangerous plants in the petrochemical industry. A detailed consequence analysis for different accidental scenarios for a storage tanks in a petrochemical complex in Iran is put forward. Credible scenarios were selected and all the effective factors that may influence the mechanism of release and dispersion of toxic materials were surveyed. Simulator software and numerical models were used to simulate the distribution of toxic material around the leak source. The results can be used in risk management and in providing an emergency response plan to counter unwanted situations in the plant. This is an abstract of a paper presented at the 7th... 

    Two new silver(I) complexes with 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz): Preparation, characterization, crystal structure and alcohol oxidation activity in the presence of oxone

    , Article Polyhedron ; Volume 29, Issue 14 , September , 2010 , Pages 2837-2843 ; 02775387 (ISSN) Najafpour, M. M ; Hołyńska, M ; Amini, M ; Kazemi, S. H ; Lis, T ; Bagherzadeh, M ; Sharif University of Technology
    Two new silver(I) complexes ((tptz)Ag2(NO3) 2 and [Ag5(tptz)4](NO3)5) with 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz) have been synthesized and characterized by X-ray diffraction, elemental analysis, 1H NMR, IR, fluorescence, UV-Vis spectroscopy and electrochemistry. Oxidation of alcohols to their corresponding aldehydes and ketones was conducted with one of the Ag complexes as a catalyst, soluble enough in organic solvent, using oxone (2KHSO5·KHSO4·K2SO4) as an oxidant under biphasic reaction conditions (CH2Cl 2/H2O) and tetra-n-butylammonium bromide as phase transfer agent under air at room temperature  

    Removal of toxic metal ions from sungun acid rock drainage using mordenite zeolite, graphene nanosheets, and a novel metal–organic framework

    , Article Mine Water and the Environment ; Volume 35, Issue 1 , 2016 , Pages 18-28 ; 10259112 (ISSN) Rahimi, E ; Mohaghegh, N ; Sharif University of Technology
    Springer Verlag  2016
    We evaluated the sorptive properties of mordenite zeolite (MOR), a copper terephthalate metal–organic framework (MOF), and graphene oxide (GO) and their potential use in treating acid rock drainage (ARD) containing Fe3+, Cu2+, Mn2+, Zn2+, Pb2+, and Cd2+ ions. MOR was prepared via a hydrothermal method, MOF was prepared via a solvothermal method, and few-layered GO nanosheets were synthesized using Hummers’ method. The aqueous contaminants were removed by chemico-physical sorption and ion exchange in batch tests. It proved possible to dramatically improve removal efficiency and sorptive capacity by optimizing experimental conditions. Magnetic MOF crystals were more efficient in removing... 

    Selective aqueous oxidation of alcohols catalyzed by copper (II) phthalocyanine nanoparticles

    , Article Comptes Rendus Chimie ; Volume 19, Issue 3 , 2016 , Pages 313-318 ; 16310748 (ISSN) Kheirjou, S ; Kheirjou, R ; Rezayan, A. H ; Shakourian Fard, M ; Mahmoudi Hashemi, M ; Sharif University of Technology
    Elsevier Masson SAS 
    A new catalyst based on metallophthalocyanine nanoparticles has been synthesized and characterized by scanning electron microscopy (SEM). The aqueous oxidation of alcohols to the corresponding carbonyl compounds (aldehydes and ketones) has been studied using tetra-n-butyl-ammonium-peroxo-monosulfate (n-Bu4NHSO5) as an oxidant and a catalytic system consisting of copper (II) phthalocyanine nanoparticles in water. The highly selective oxidation gave excellent yields of related aldehydes or ketones without remarkable over-oxidation of the carboxylic acids. Organic co-solvents, surfactants, and co-catalysts were not used in this catalytic strategy. This strategy was green and time effective. The... 

    A simple, economical, and catalyst-free oxidation of thiols to disulfides

    , Article Journal of Sulfur Chemistry ; Volume 30, Issue 6 , 2009 , Pages 578-580 ; 17415993 (ISSN) Ghafuri, H ; Hashemi, M. M ; Sharif University of Technology
    A simple, rapid, and highly efficient method for the preparation of symmetrical aliphatic, aromatic, and heteroaromatic disulfides is reported. Addition of NBS to an alkyl- or arylthiol under catalyst-free conditions in dichloromethane solution produces the corresponding disulfides in nearly quantitative yields  

    Comparison of isothermal with cyclic oxidation behavior of “Cr-Aluminide” coating on inconel 738LC at 900 °C

    , Article Oxidation of Metals ; Volume 87, Issue 1-2 , 2017 , Pages 57-74 ; 0030770X (ISSN) Salehi Doolabi, M ; Ghasemi, B ; Sadrnezhaad, S. K ; Feizabadi, A ; HabibollahZadeh, A ; Salehi Doolabi, D ; AsadiZarch, M ; Sharif University of Technology
    Springer New York LLC  2017
    A two-step pack cementation technique was used to cover nickel-based IN-738LC superalloy with a Cr-aluminide coating layer. The IN-738LC/Cr-aluminide samples were oxidized at 900 °C for 350 and 700 h, isothermally, and 175 and 350 h, cyclically. Each cycle lasted for 25 h. Effects of the isothermal and the cyclic oxidation on (a) morphology, (b) new-phase formation, (c) weight gain, and (d) oxidation reactions were investigated by scanning electron microscopy, electron dispersive spectroscopy, X-ray diffraction, and weight gain measurements. From results, it was concluded that the oxygen attack was more severe during the cyclic oxidation than the isothermal procedure. Kinetics of the... 

    Synthesis, characterization and biological evaluation of a well dispersed suspension of gallium-68-labeled magnetic nanosheets of graphene oxide for in vivo coincidence imaging

    , Article Radiochimica Acta ; Volume 105, Issue 1 , 2017 , Pages 65-73 ; 00338230 (ISSN) Fazaeli, Y ; Rahighi, R ; Tayyebi, A ; Feizi, S ; Sharif University of Technology
    Walter de Gruyter GmbH  2017
    Graphene oxide (GO) nanosheets were hybridized with Fe3O4 nanoparticles (NPs) to form magnetic GO (MGO) and were further labeled by [68Ga]GaCl3 as a potential drug delivery system. Paper chromatography, Fourier transform infra red (FTIR) spectroscopy, low-angle X-ray diffraction (XRD), CHN and atomic force microscopy (AFM) were utilized to characterize the trinary composite ([68Ga]@MGO). Biological evaluations of the prepared nanocomposite were performed in normal Sprague Dawley rats and it was found to be a possible host for theranostic radiopharmaceuticals. The results showed that the grafting of Fe3O4 NPs on nanocomposite reduced the unwanted liver and spleen uptakes and increased the... 

    Fabrication of chitosan/poly(lactic acid)/graphene oxide/TiO2 composite nanofibrous scaffolds for sustained delivery of doxorubicin and treatment of lung cancer

    , Article International Journal of Biological Macromolecules ; 2017 ; 01418130 (ISSN) Samadi, S ; Moradkhani, M ; beheshti, H ; Irani, M ; Aliabadi, M ; Sharif University of Technology
    Elsevier B.V  2017
    In this work, the synthesized graphene oxide/TiO2/doxorubicin (GO/TiO2/DOX) composites were loaded into the chitosan/poly(lactic acid) (PLA) solutions to fabricate the electrospun chitosan/PLA/GO/TiO2/DOX nanofibrous scaffolds via electrospinning process. The synthesized composites and nanofibers were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis. Three-factor three-level central composite design was used to determine the influence of PLA to chitosan ratio, TiO2/DOX content and GO/TiO2/DOX content on the release of DOX from nanofibrous scaffolds. Drug loading efficiency and drug release behavior from... 

    Photo-Fenton like degradation of catechol using persulfate activated by UV and ferrous ions: Influencing operational parameters and feasibility studies

    , Article Journal of Molecular Liquids ; Volume 249 , 2018 , Pages 463-469 ; 01677322 (ISSN) Delavaran Shiraz, A ; Takdastan, A ; Borghei, S. M ; Sharif University of Technology
    Elsevier B.V  2018
    In the present study, photo-Fenton degradation of catechol from aqueous solution was carried out using UV light and iron ions (Fe2+) as activators of persulfate (PS). Catechol degradation from solution was studied under different experimental variables such as solution pH (2.0–10.0), iron dosages (0.1–0.5 g/L), persulfate loadings (1.0–5.0 mM), initial catechol concentrations (20–100 mg/L) and scavengers (TBA and IPA). The comparative study of catechol removal showed that among the applied approaches, the order of degradation of catechol is as follows: PS/Fe2 +/UV > PS/Fe2 + > UV/PS > PS > UV. Furthermore, higher catechol degradation was observed with increasing iron dosage and PS... 

    Synthesis and cation-exchange behavior of expanded MoS2 nanosheets for anticorrosion applications

    , Article 2017 INN International Conference/Workshop on Nanotechnology and Nanomedicine, NTNM 2017, 2 May 2017 through 3 May 2017 ; Volume 5, Issue 7 , 2018 , Pages 15573-15579 ; 22147853 (ISSN) Haddadi, S. A ; Amini, M ; Ghaderi, S ; Ramazani, A ; Sharif University of Technology
    Elsevier Ltd  2018
    Molybdenum disulfide (MoS2), a 2D layered structure, because of its unique properties has widely attracted many researchers. In this study, by employing physical and chemical methods, not only layers of MoS2 have been intercalated, but also their surface properties enhanced. Low-dimensional and potential properties of intercalated MoS2 nanosheets are the aim of many researches. Here, we report a novel four step method to intercalate the layers of MoS2 nanosheets successfully using acid treatment, sonication, oxidization and thermal shocking. The other goal in this study is to evaluate the cation exchange ability and anticorrosion performance of the Ce3+ doped MoS2 nanosheets. The... 

    Activation of hydrocarbon C-H bonds by iodosylbenzene: How does it compare with iron(iv)-oxo oxidants?

    , Article Chemical Communications ; Issue 12 , 2009 , Pages 1562-1564 ; 13597345 (ISSN) Kim, S. J ; Latifi, R ; Kang, H. Y ; Nam, W ; De Visser, S. P ; Sharif University of Technology
    Combined experimental and theoretical studies on the reactivity of iodosylbenzene (PhIO) show that PhIO is capable of activating weak C-H bonds of hydrocarbons via a hydrogen abstraction mechanism. © 2009 The Royal Society of Chemistry