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    Synthesis and characterization of poly(methacrylates) containing spiroacetal and norbornene moieties in side chain [electronic resource]

    , Article Journal of Applied Polymer Science ; Volume 77, Issue 1, pages 30–38, 5 July 2000 Pourdjavadi, A. (Ali) ; Mirjalili, Bibi Fatemeh ; Sharif University of Technology
    Abstract
    A four-step synthetic strategy was applied to achieve novel methacrylic monomers. 5-Norbornene-2,2-dimethanol was prepared from a Diels–Alder reaction of cyclopentadiene and acrolein, followed by the treatment of the adduct with an HCHO/KOH/MeOH solution. The resulting 1,3-diol (1) was then acetalized with different aromatic aldehydes having OH groups on the ring to produce four spiroacetal derivatives. The reaction of methacryloyl chloride with the phenolic derivatives led to four new methacrylic monomers that were identified spectrochemically (mass, FTIR, 1H-NMR, and 13C-NMR spectroscopy). Free radical solution polymerization was used to prepare novel spiroacetal–norbornene containing... 

    Synthesis and characterization of carbon-stabilized magnesium nanoparticles

    , Article Journal of Cluster Science ; 2016 , Pages 1-9 ; 10407278 (ISSN) Safaei, S ; Asgari, F ; Arzi, M ; Hojaji, A ; Sadrnezhaad, S. K ; Sharif University of Technology
    Springer New York LLC  2016
    Abstract
    Magnesium nanopowder has attracted many interests in the recent years, which has a very difficult and costly synthesis process because of its high activity. In this work, magnesium nanoparticles stabilized with amorphous carbon (Mg–C nanoparticles) were synthesized by submerged arc discharge technique in kerosene. The arc discharge was generated between two electrodes of magnesium at the arc current of 1 A and arc voltage of 50 V. Mg–C nanoparticles were characterized by various techniques. Dynamic light scattering result indicated that size of magnesium nanoparticles is about 35 nm. X-ray diffraction showed that the produced sample consisted of hexagonal magnesium and amorphous carbon and... 

    Synthesis and characterization of carbon-stabilized magnesium nanoparticles

    , Article Journal of Cluster Science ; Volume 28, Issue 3 , 2017 , Pages 881-889 ; 10407278 (ISSN) Safaei, S ; Asgari, F ; Arzi, M ; Hojaji, A ; Sadrnezhaad, S. K ; Sharif University of Technology
    Springer New York LLC  2017
    Abstract
    Magnesium nanopowder has attracted many interests in the recent years, which has a very difficult and costly synthesis process because of its high activity. In this work, magnesium nanoparticles stabilized with amorphous carbon (Mg–C nanoparticles) were synthesized by submerged arc discharge technique in kerosene. The arc discharge was generated between two electrodes of magnesium at the arc current of 1 A and arc voltage of 50 V. Mg–C nanoparticles were characterized by various techniques. Dynamic light scattering result indicated that size of magnesium nanoparticles is about 35 nm. X-ray diffraction showed that the produced sample consisted of hexagonal magnesium and amorphous carbon and... 

    Synthesis and characterization of a new group of Exo-coordinating o2n2-donor macrocycles

    , Article Australian Journal of Chemistry ; Volume 69, Issue 3 , 2016 , Pages 273-278 ; 00049425 (ISSN) Ghanbari, B ; Safarkoopayeh, B ; Kia, R ; Raithby, P.R ; Sharif University of Technology
    CSIRO  2016
    Abstract
    The reaction of 15-18 membered benzodiazacrown ethers with salicylaldehyde afforded n-membered O2N2-donor macrocyclic ligands mounted with 1,3-diazacyclohexane subrings (1-4) in high yields. The products were characterized by FT-IR, 1H, 13C NMR spectroscopy, elemental analyses, and single crystal X-ray studies. The solid state structures revealed strong intramolecular hydrogen bonding between the pendant phenolic group and the tertiary nitrogen of the corresponding macroring  

    Synthesis and characterization of NiCo2O4 nanorods for preparation of supercapacitor electrodes

    , Article Journal of Solid State Electrochemistry ; Vol. 19, Issue. 1 , 2014 , pp. 269-274 ; ISSN: 1432-8488 Jokar, E ; Zad, A. I ; Shahrokhian, S ; Sharif University of Technology
    Abstract
    Here, a solvothermal method for synthesis of porous Ni–Co binary oxide (NiCo2O4) nanorods followed by thermal decomposition is described. The prepared nanorods were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer Emmett Teller (BET) methods. These porous NiCo2O4 nanostructures were promising candidates in the development of high capacity supercapacitors and having excellent cycling performance due to high specific surface area. In addition, the influence of annealing rate on the structure and electrochemical behavior of the synthesized nanorods was investigated. The results showed that the annealing rate had a direct effect on the crystalline... 

    Synthesis and characterization of semi-conductive nanocomposite based on hydrolyzed collagen and in vitro electrically controlled drug release study

    , Article Polymer (United Kingdom) ; Volume 76 , October , 2015 , Pages 287-294 ; 00323861 (ISSN) Pourjavadi, A ; Doroudian, M ; Sharif University of Technology
    Elsevier Ltd  2015
    Abstract
    In this study, a semi-conductive nanocomposite for electrically controlled drug delivery is introduced. Hydrolyzed collagen known as a naturally abundant polypeptide was modified with polycaprolactone. This modification changed the mechanical properties of the hydrolyzed-collagen. A hydrogel compound was synthesized through radical co-polymerization of acrylic acid on the backbone of this biocompatible polymer in the presence of a crosslinker. The reaction parameters affecting the water absorbency of the hydrogel were optimized using Taguchi method. In situ polymerization of aniline, incorporated conductive nanofiber pathways throughout the hydrogel matrix. 1H NMR, TGA, AFM, SEM, FTIR,... 

    Supercritical synthesis and characterization of graphene-pbs quantum dots composite with enhanced photovoltaic properties

    , Article Industrial and Engineering Chemistry Research ; Volume 54, Issue 30 , 2015 , Pages 7382-7392 ; 08885885 (ISSN) Tayyebi, A ; Tavakoli, M. M ; Outokesh, M ; Shafiekhani, A ; Simchi, A ; Sharif University of Technology
    American Chemical Society  2015
    Abstract
    Lead sulfide quantum dots (PbS QDs) were decorated onto a graphene surface in a semi-core-shell structure using supercritical ethanol. The temperature of ethanol played significant role in controlling size and agglomeration of QDs as well as the extent of reduction of graphene. Average size of the QDs was estimated by transmission electron microscopy to be around 3.96 nm and by quantum models to be about 4.34 nm. PbS QDs prepared at 330 °C were of high purity, and the yield was 99%. Instrumental and chemical analyses demonstrated formation of a strong bond between PbS QDs and graphene, through a Pb-O-C bridge. UV and photoluminescence measurements along with theoretical considerations... 

    Synthesis and characterization of electrochemically grown CdSe nanowires with enhanced photoconductivity

    , Article Journal of Materials Science: Materials in Electronics ; Volume 26, Issue 3 , March , 2015 , Pages 1395-1402 ; 09574522 (ISSN) Kalhori, H ; Irajizad, A ; Azarian, A ; Ashiri, R ; Sharif University of Technology
    Springer New York LLC  2015
    Abstract
    CdSe nanowires were grown in polycarbonate track etched membrane with pore diameter of 80 nm by an electrochemical deposition technique. The mechanism of the growth was studied during the potentiostatic deposition of nanowires. X-ray photoelectron spectroscopy and energy dispersive spectrometry results showed binding of fragments and fraction of atoms for the CdSe nanowires. Microstructure and morphology of synthesized CdSe nanowires were observed by scanning electron microscopy. Optical spectrophotometry technique was used to determine the energy band gap of CdSe nanowires. It was found that the nanowires were resistive in the dark and exhibited a pronounced visible light photoconductivity.... 

    Synthesis and characterization of magnetic silica-supported Mn(II)-substituted polyoxophosphotungstate as catalyst in sulfoxidation reaction

    , Article Journal of Nanoparticle Research ; Volume 18, Issue 10 , 2016 ; 13880764 (ISSN) Moradi Shoeili, Z ; Zare, M ; Bagherzadeh, M ; Sharif University of Technology
    Springer Netherlands  2016
    Abstract
    Abstract: Polyoxometalate-functionalized magnetic nanoparticles (Fe3O4@SiO2–MnPOW) were successfully synthesized via covalent anchoring of Mn(II)-substituted phosphotungstate on ammonium-modified Fe3O4@SiO2 nanoparticles. The complete characterization of nanoparticles has been carried out by scanning electron microscope, energy-dispersive X-ray, X-ray diffraction, Fourier transform infrared and elemental analysis. The resulting nanocomposites were efficient catalysts for the selective oxidation of sulfides with different green oxidants in good to excellent yields and also high selectivity. Leaching and recycling tests showed that the nanocatalyst can be reused several times without... 

    Synthesis and characterization of a new nanocomposite by filling of CNT with CoFe2O4 Magnetic nanoparticles and grafting to polymer

    , Article Nano ; Volume 4, Issue 6 , 2009 , Pages 371-376 ; 17932920 (ISSN) Sepahvand, R ; Adeli, M ; Actinchap, B ; Bahari, A ; Sharif University of Technology
    Abstract
    In this work, the synthesis and characterization of a new nanocomposite from carbon nanotubes-graft-polymer (CNTs-g-P) is reported. The products were obtained by the filling of multi-walled carbon nanotubes (MWCNTs) (inner diameter 2040 nm) with CoFe2O4 magnetic nanoparticles, been grafted with poly (caprolactone). The filling process was carried out by using acid treatment through wet chemistry. The structure and the properties of the new nanocomposite were studied with TEM, VSM, TGA, and spectroscopic techniques. © 2009 World Scientific Publishing Company  

    Synthesis and characterization of polyamide membrane for the separation of acetic acid from water using RO process

    , Article Membrane Water Treatment ; Volume 8, Issue 4 , 2017 , Pages 323-336 ; 20058624 (ISSN) Mirfarah, H ; Mousavi, S. A ; Mortazavi, S. S ; Sadeghi, M ; Bastani, D ; Sharif University of Technology
    Techno Press  2017
    Abstract
    The main challenge in many applications of acetic acid is acid dehydration and its recovery from wastewater streams. Therefore, the performance of polyamide thin film composite is evaluated to separate acetic acid from water. To reach this goal, the formation of polyamide layer on polysulfone support membrane was investigated via interfacial polymerization (IP) of meta-phenylenediamine (MPD) in water with trimesoyl chloride (TMC) in hexane. Also, the effect of synthesis conditions, such as concentration of monomers and curing temperature on separation of acetic acid from water were investigated by reverse osmosis process. Moreover, the separation mechanism was discussed. The solute... 

    Synthesis and characterization of new triphenylamine-based dyes with novel anchoring groups for dye-sensitized solar cell applications

    , Article Journal of Materials Science: Materials in Electronics ; Volume 28, Issue 2 , 2017 , Pages 1859-1868 ; 09574522 (ISSN) Salimi Beni, A ; Hosseinzadeh, B ; Azari, M ; Ghahary, R ; Sharif University of Technology
    Springer New York LLC  2017
    Abstract
    Three new chromophores based on the triphenylamine (MM, DM, DN) with various novel electron withdrawing anchoring groups have been synthesized for use in dye-sensitized solar cells (DSSCs). The sensitizers were characterized by 1H and 13C NMR, Mass, UV–Vis, and electrochemical analysis. The HOMO and LUMO electron distributions of the sensitizers were calculated using density functional theory on a B3LYP level for geometry optimization. The DSSC device based on DM dye showed the best photovoltaic performance among MM and DN dyes: maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 98 %, short circuit current (JSC) of 4.58 mA/cm2, open circuit voltage (VOC) of... 

    Synthesis and characterization of YBaCu2O5-δ compound

    , Article Physica C: Superconductivity and its Applications ; Volume 548 , 15 May , 2018 , Pages 112-115 ; 09214534 (ISSN) Ehsandoust, A ; Sandoghchi, M ; Mokhtari, P ; Akhavan, M ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    YBaCu2O5 compound as one of the possible microstructures of Y3Ba5Cu8O19 has been synthesized. The X-ray diffraction analysis of this compound indicates that its formation is accompanied with the formation of YBa2Cu3O7-δ. The observed superconductivity around ∼92 K supports this. So, it seems that YBa2Cu3O7-δ is responsible for the observed superconductivity in YBaCu2O5, and this phase is not an independent superconducting phase. Consequently, the overall effect of the YBaCu2O5 formation during the Y3Ba5Cu8O19 fabrication process could be a reduction in Tc. © 2018 Elsevier B.V  

    Investigation of complexation behavior of the dithiocarbamates of N 1 ,N n -dicinnamylalkane-1,n-diamines with metals

    , Article Journal of Molecular Structure ; Volume 1180 , 2019 , Pages 188-195 ; 00222860 (ISSN) Ziyaei Halimehjani, A ; Soleymani Movahed, F ; Fathi, M. B ; Daliri, R ; Saidi, M. R ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    Synthesis and characterization of metal dithiocarbamate complexes of N 1 ,N 3 -dicinnamylpropane-1,3-diamine, N 1 ,N 4 -dicinnamylbutane-1,4-diamine and N 1 ,N 6 -dicinnamylhexane-1,6-diamine are reported. The ligands are prepared using cinnamaldehyde and primary diamines to provide the corresponding diimines, followed by reduction with NaBH 4 to afford the corresponding secondary diamines. Diamines react with carbon disulfide in basic medium to furnish the corresponding bis(dithiocarbamate) salts, which underwent complexation with metals. The prepared complexes were characterized by IR, 1 H and 13 C NMR, TGA and elemental analyses. Although the dinuclear metal dithiocarbamate macrocyclic... 

    Synthesis and characterization of poly(L-lactide)-block-poly(ε-caprolactone)-grafted titanium dioxide nanoparticles via ring-opening in situ grafting polymerization

    , Article Polymer Composites ; Volume 42, Issue 8 , 2021 , Pages 3722-3731 ; 02728397 (ISSN) Ebrahimi, H ; Sharif, F ; Ramezani Saadat Abadi, A ; Sharif University of Technology
    John Wiley and Sons Inc  2021
    Abstract
    The synthesis of nanocomposites via in situ grafting polymerization due to its ability to produce polymeric materials with promising microscopic and macroscopic characteristics is becoming very attractive. In this paper, different poly(L-Lactide)-block-poly(ε-caprolactone) (PLLA-b-PCL) copolymers were in situ synthesized in the presence of modified titanium dioxide (TiO2) nanoparticles (mTNP) as the initiator and stannous octoate as the catalyst. The surface of TiO2 was modified by grafting aminopropyl trimethoxy silane to improve initiator efficiency. Copolymers with 90/10, 70/30, and 50/50 mass ratio of L-lactide/ ε-caprolactone and 5 wt% of mTNP (proportional to ε-caprolactone) were... 

    The photochromic switchable imidazoles: Their genesis, development, synthesis, and characterization

    , Article Dyes and Pigments ; Volume 203 , 2022 ; 01437208 (ISSN) Bagheri, M ; Mirzaee, M ; Hosseini, S ; Gholamzadeh, P ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Switchable photochromic dyes have benefited greatly from the use of heterocyclic chemicals. The imidazole group is particularly essential because it can be transformed into dimers, which can then be radicalized in the presence of light photons. Imidazole dimers have been optimized throughout thirty years of research, allowing derivatives with diverse colors, quick reversibility, and sensitivity to different wavelengths from UV to near IR ranges. These imidazole dimers are interesting to be used in the matrices of polymers, hydrogels, glasses, solar cells, and even pharmaceuticals. The goal of this review is to look at the history, development, and future of imidazole dimers. We will also... 

    Metal-Organic cubane cage with trimethylplatinum(IV) vertices

    , Article Inorganic Chemistry ; Volume 61, Issue 1 , 2022 , Pages 15-19 ; 00201669 (ISSN) Hendi, Z ; Jamali, S ; Mahmoudi, S ; Samouei, H ; Nayeri, S ; Chabok, S. M. J ; Jamshidi, Z ; Sharif University of Technology
    American Chemical Society  2022
    Abstract
    Herein we describe the synthesis and characterization of the first platinum(IV) metal-organic cage [(Me3PtIV)8(byp)12](OTf)8 (2), in which the organometallic moieties trimethylplatinum(IV) (PtMe3) occupied the corners of a cubane structure and 4,4′-bipyridine ligands used as linkers. The first-principles density functional theory calculations showed that the highest occupied molecular orbitals were localized on the PtMe3 moieties, while the lowest unoccupied molecular orbitals were distributed on the organic linkers. © 2021 American Chemical Society  

    Synthesis and characterization of 1-amidino-O-alkylureas metal complexes as α- glucosidase Inhibitors: Structure-activity relationship, molecular docking, and kinetic studies

    , Article Journal of Molecular Structure ; Volume 1250 , 2022 ; 00222860 (ISSN) Moghaddam, F. M ; Daneshfar, M ; Daneshfar, Z ; Iraji, A ; Samandari Najafabad, A ; Faramarzi, M. A ; Mahdavi, M ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    In the present study, metal complexes of 1-amidino-O-alkylureas were designed, synthesized and characterized by elemental analyses, FT-IR spectra, XRD, Mass analyses and scanning electron microscopy (SEM). All synthesized complexes were screen as α-Glucosidase inhibitors. According to the in vitro results, the Cu (II) complexes showed superior potency compared to other tested metal complexes. Particularly, [Cu(L-Me)2](Cl)2 (1b) showed the strongest inhibition against α-Glucosidase with an IC50 value of 2.75 ± 0.3 µM which was comparable to that of acarbose (IC50 = 750 µM). These findings are supported by the ligands and enzyme interactions through molecular docking. © 2021 Elsevier B.V  

    Synthesis and characterization of pure metallic titanium nanoparticles by an electromagnetic levitation melting gas condensation method

    , Article RSC Advances ; Vol. 4, issue. 14 , 2014 , pp. 7104-7108 ; ISSN: 20462069 Mohammadi, A. V ; Halali, M ; Sharif University of Technology
    Abstract
    Pure titanium nanoparticles were synthesized by utilizing an Electromagnetic Levitation Melting Gas Condensation (ELM-GC) method. Pure bulk titanium samples were melted and evaporated by electromagnetic levitation technique in an inert gas atmosphere in a silica tube. Titanium nanoparticles were formed from ascending vapor by employing high purity argon and helium as carrier gases and cooling agents. Particle size and morphology of the produced nanoparticles were studied by Field-Emission Scanning Electron Microscopy (FE-SEM) and Dynamic Light Scattering (DLS) analysis. Results showed almost spherical nanoparticles with a narrow size distribution under both cooling atmospheres. The purity of... 

    Synthesis and characterization of co-doped TiO2 thin films on glass-ceramic

    , Article Materials Science in Semiconductor Processing ; Vol. 26, Issue 1 , October , 2014 , pp. 41-48 ; ISSN: 13698001 Ahmadi, N ; Nemati, A ; Solati-Hashjin, M ; Sharif University of Technology
    Abstract
    In this research, an attempt was made to improve TiO2 photo-catalyst properties, thus pure, N-Ce co-doped TiO2 thin films were prepared on glass-ceramic substrate using a sol-gel dip-coating technique. The samples were calcinated in air at 475 °C, 550°C, and 650°C for 2 h. The result of simultaneous thermal analysis (STA) and X-ray diffraction (XRD) showed that the presence of Ce in TiO2 could inhibit the phase transformation from anatase to rutile and enhance the thermal stability, and anatase was the dominant phase in N-Ce co-doped TiO2 samples. Also based on the results, the doping results in decreasing the size of TiO 2 crystallite. The results of ultra violet-visible light diffuse...