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    Removal of toxic heavy metal ions from waste water by functionalized magnetic core-zeolitic shell nanocomposites as adsorbents

    , Article Environmental Science and Pollution Research ; Volume 20, Issue 6 , 2013 , Pages 3900-3909 ; 09441344 (ISSN) Padervand, M ; Gholami, M. R ; Sharif University of Technology
    Functionalized magnetic core-zeolitic shell nanocomposites were prepared via hydrothermal and precipitation methods. The products were characterized by vibrating sample magnetometer, X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption isotherms, and transmission electron microscopy analysis. The growth of mordenite nanocrystals on the outer surface of silica-coated magnetic nanoparticles at the presence of organic templates was well approved. The removal performance and the selectivity of mixed metal ions (Pb2+ and Cd2+) in aqueous solution were investigated via the sorption process. The batch method was employed to study the sorption kinetic,... 

    A low power 1-V 10-bit 40-MS/s pipeline ADC

    , Article 2011 18th IEEE International Conference on Electronics, Circuits, and Systems, ICECS 2011, 11 December 2011 through 14 December 2011 ; December , 2011 , Pages 212-215 ; 9781457718458 (ISBN) Hashemi, M ; Sharifkhani, M ; Gholami, M ; Sharif University of Technology
    A low power 10 bit, 40 MS/s pipeline analog to digital converter is presented. A number of low-power techniques are proposed in various levels of abstraction. In circuit level, a low power class A/AB opamp with direct common-mode-feedback circuit (CMFB) is proposed which significantly reduces power in the opamps. In backend design, optimal series capacitors are layed out to break the deadlock between the mismatch and loading effect of the first stage capacitors. A customized software tool is developed based on the proposed opamp and architecture which provides optimum stage scaling factors, tail current and opamp transistor sizes. Simulations in 0.13um CMOS technology show that the ADC... 

    Biodegradable ionic liquids: effects of temperature, alkyl side-chain length, and anion on the thermodynamic properties and interaction energies as determined by molecular dynamics simulations coupled with ab initio calculations

    , Article Industrial and Engineering Chemistry Research ; Volume 54, Issue 46 , November , 2015 , Pages 11678-11700 ; 08885885 (ISSN) Fakhraee, M ; Gholami, M. R ; Sharif University of Technology
    American Chemical Society  2015
    The effects of incorporating the ester functional group (-C=OO-) into the side chain of the 1-alkyl-3-methylimidazolium cation ([C1COOCnC1im]+, n = 1, 2, 4) paired with [Br]-, [NO3]-, [BF4]-, [PF6]-, [TfO]-, and [Tf2N]- anions on the various thermodynamic properties and interaction energies of these biodegradable ionic liquids (ILs) were investigated by means of molecular dynamics (MD) simulations combined with ab initio calculations in the temperature range of 298-550 K. Excluding the simulated density, the highest values of the volumetric properties such as molar volume, isobaric expansion coefficient, and isothermal compressibility coefficient can be attributed to the largest cation... 

    Acid blue 92 photocatalytic degradation in the presence of scavengers by two types photocatalyst

    , Article Environmental Progress and Sustainable Energy ; Volume 31, Issue 3 , 2012 , Pages 371-378 ; 19447442 (ISSN) Elahifard, M. R ; Gholami, M. R ; Sharif University of Technology
    Two types of nanosized photocatalyst, TiO 2 P-25 and ap/Ag/AgBr/TiO 2, were used for decolorization of Acid Blue 92 (AB92) in dark, visible light (V-L), and UV media. Under UV and V-L, the effect of three possible photodegradation processes of AB92 including photocatalytic degradation, self-photosensitization, and direct photolysis were studied. Results showed that in UV/photocatalysts, photocatalytic degradation is the major process for photodecolorization. However, in the presence of TiO 2, self-photosensitization has the major role under V-L. Because of the presence of AgBr as photoactive center in ap/Ag/AgBr/TiO 2, the main process is the photocatalytic degradation in V-L. By using... 

    Probing the effects of the ester functional group, alkyl side chain length and anions on the bulk nanostructure of ionic liquids: A computational study

    , Article Physical Chemistry Chemical Physics ; Volume 18, Issue 14 , 2016 , Pages 9734-9751 ; 14639076 (ISSN) Fakhraee, M ; Gholami, M. R ; Sharif University of Technology
    Royal Society of Chemistry 
    The effects of ester addition on nanostructural properties of biodegradable ILs composed of 1-alkoxycarbonyl-3-alkyl-imidazolium cations ([C1COOCnC1im]+, n = 1, 2, 4) combined with [Br]-, [NO3]-, [BF4]-, [PF6]-, [TfO]-, and [Tf2N]- were explored by using the molecular dynamics (MD) simulations and quantum theory of atoms in molecules (QTAIM) analysis at 400 K. Various thermodynamic properties of these ILs were extensively computed in our earlier work (Ind. Eng. Chem. Res., 2015, 54, 11678-11700). Nano-scale segregation analysis demonstrates the formation of a small spherical island-like hydrocarbon within the continuous ionic domain for ILs with short alkyl side chain ([C1COOC1C1im]), and a... 

    AgPt nanoparticles supported on magnetic graphene oxide nanosheets for catalytic reduction of 4-nitrophenol: studies of kinetics and mechanism

    , Article Applied Organometallic Chemistry ; Volume 31, Issue 11 , 2017 ; 02682605 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    AgxPt100−x (x = 0, 25, 50, 75 and 100) nanoparticles were grown on the surface of magnetic graphene oxide nanosheets (Fe3O4@GO) for the first time. The as-prepared nanocomposites were characterized using various techniques such as Fourier transform infrared spectroscopy, powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller surface area analysis, vibrating sample magnetometry and thermogravimetric analysis. The Fe3O4@GO-AgxPt100−x catalysts were applied in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol using sodium borohydride (NaBH4). The synthesized nanocomposites... 

    Pt–NiO–Al2O3/G derived from graphene-supported layered double hydroxide as efficient catalyst for p-nitrophenol reduction

    , Article Research on Chemical Intermediates ; Volume 43, Issue 10 , 2017 , Pages 5829-5839 ; 09226168 (ISSN) Akbarzadeh, E ; Gholami, M. R ; Sharif University of Technology
    The present work reports the synthesis of a Pt-modified NiO–Al2O3 nanocomposite derived from graphene-supported layered double hydroxide (Pt–NiO/G) and demonstrates its catalytic activity. The resulting Pt–NiO/G nanocomposite was characterized by FT-IR, XRD, FE-SEM, TEM and XPS techniques and used for catalytic reduction of p-nitrophenol (P-NP) to p-aminophenol (P-AP). The influence of graphene on catalytic activity was comparatively considered by preparation of Pt–NiO nanoparticles derived from layered double hydroxide. The superior catalytic performance of Pt–NiO/G was ascribed to the synergistic effect between Pt and NiO. Furthermore, reduction of P-NP was considered to follow a... 

    Increase in the β-sheet character of an amyloidogenic peptide upon adsorption onto gold and silver surfaces

    , Article ChemPhysChem ; Volume 18, Issue 5 , 2017 , Pages 526-536 ; 14394235 (ISSN) Soltani, N ; Gholami, M. R ; Sharif University of Technology
    Wiley-VCH Verlag  2017
    Fibrillation of amyloid beta (Aβ) peptide is the hallmark of Alzheimer's disease. Given that interactions at the bio–nano interface affect the fibrillation tendency of this peptide, an understanding of the interactions at Aβ peptide–inorganic surfaces on the microscopic level can help to determine the possible neurotoxicity of nanoparticles. Here, the interactions between a fibril-forming peptide, Aβ25–35, and (111) and (100) facets of gold and silver surfaces have been studied by conducting atomistic molecular dynamics simulations. The obtained results indicate that the adsorption onto gold and silver surfaces force the peptide into the β-sheet-rich conformations, which is prone to... 

    Kinetic analysis of the reduction of 4-nitrophenol catalyzed by CeO2 nanorods-supported CuNi nanoparticles

    , Article Industrial and Engineering Chemistry Research ; Volume 56, Issue 5 , 2017 , Pages 1159-1167 ; 08885885 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    American Chemical Society  2017
    CuxNi100-x (x = 0, 20, 40, 60, 80, and 100) nanoparticles were uniformly grown on the surface of CeO2 by the liquid impregnation method. The as-prepared nanocomposite abbreviated CuxNi100-x-CeO2 was characterized by various techniques including, X-ray powder diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, Brunauer-Emmett-Teller surface area analyzer, and transmission electron microscopy. The catalytic activity of CuxNi100-x-CeO2 nanocomposites was investigated in 4-nitrophenol (4-NP) reduction reaction. Among the synthesized nanocomposites, Cu60Ni40-CeO2 exhibited the best catalytic activity (rate constant as 0.1654 s-1) with high recyclability... 

    M: XNi100- X (M = Ag, and Co) nanoparticles supported on CeO2 nanorods derived from Ce-metal organic frameworks as an effective catalyst for reduction of organic pollutants: Langmuir-Hinshelwood kinetics and mechanism

    , Article New Journal of Chemistry ; Volume 41, Issue 19 , 2017 , Pages 10948-10958 ; 11440546 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    Royal Society of Chemistry  2017
    In this study, AgxNi100-x, and CoxNi100-x (x = 0, 20, 40, 60, 80, and 100) bimetallic nanoparticles were successfully decorated on the surface of CeO2 nanorods derived from Ce-metal organic frameworks (Ce-MOF). The as-synthesized products were characterized using different techniques including XRD, FE-SEM, EDX, TEM, ICP, and BET. The as-prepared nanocomposites showed remarkable catalytic activity towards the reduction of organic pollutants such as 4-nitrophenol (4-NP), and rhodamine-B dye (RhB) by NaBH4 solution, with high stability and reusability for five consecutive cycles. The obtained results indicated that among these nanocomposites, Ag80Ni20@CeO2, and Co60Ni40@CeO2 exhibited the best... 

    Engineering a highly dispersed core@shell structure for efficient photocatalysis: a case study of ternary novel BiOI@MIL-88A(Fe)@g-C3N4 nanocomposite

    , Article Materials Research Bulletin ; Volume 106 , 2018 , Pages 93-102 ; 00255408 (ISSN) Gholizadeh Khasevani, S ; Gholami, M. R ; Sharif University of Technology
    Ternary novel BiOI@MIL-88A(Fe)@g-C3N4 nanocomposite with core@shell structure was successfully synthesized by hydrothermal method. fabricated photocatalysts were characterized and results confirmed the formation of MIL-88A(Fe)@g-C3N4 core@shell structure and subsequently BiOI decoration on the surface of MIL-88A(Fe)@g-C3N4. Photocatalytic performances of prepared samples were investigated for degradation of Acid Blue 92 (AB92), Rhodamine B (RhB) and phenol under visible irradiation. It is clearly demonstrated that the as-prepared ternary BiOI@MIL-88A(Fe)@g-C3N4 composites exhibits exceptional visible-light photocatalytic activities for cationic, anionic as well as neutral pollutant molecules... 

    Cyclohexene oxidation catalyzed by flower-like core-shell Fe3O4@Au/metal organic frameworks nanocomposite

    , Article Materials Chemistry and Physics ; Volume 213 , July , 2018 , Pages 472-481 ; 02540584 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    Elsevier Ltd  2018
    In this study, Fe3O4@Au/metal-organic frameworks (Fe3O4@Au/MOF) nanocomposite with flower-like core-shell structure was successfully synthesized via a hydrothermal route. The as-prepared catalyst was characterized using different techniques such as FT-IR, XRD, TEM, EDX, VSM, TGA, BET, and ICP. This nanocomposite exhibited an excellent catalytic performance in selective oxidation of cyclohexene to 2-cyclohexene-1-one by using molecular oxygen as green oxidant. The influence of reaction conditions including, pressure of molecular oxygen, temperature, time, solvent, and amount of catalyst on conversion and selectivity of products were evaluated. The activation energy (Ea) of the reaction was... 

    Fabrication of novel ternary Au/CeO2@g-C3N4 nanocomposite: kinetics and mechanism investigation of 4-nitrophenol reduction, and benzyl alcohol oxidation

    , Article Applied Physics A: Materials Science and Processing ; Volume 124, Issue 6 , 2018 ; 09478396 (ISSN) Kohantorabi, M ; Gholami, M. R ; Sharif University of Technology
    Springer Verlag  2018
    Abstract: Au nanoparticles supported on cerium oxide/graphitic carbon nitride (CeO2@g-C3N4) was synthesized and used as heterogeneous catalyst in redox reaction. The catalyst was characterized by different techniques such as FT-IR, XRD, FE-SEM, EDS, TEM, BET, TGA, and ICP. The as-prepared ternary nanocomposite was used as an effective catalyst for the reduction of toxic 4-nitrophenol to useful 4-aminophenol by NaBH4. The rate constant value of reduction reaction reached up to 0.106 s−1 by Au/CeO2@g-C3N4, which was 3.8, and 8.8 times higher than that of Au@CeO2 (0.028 s−1), and Au@g-C3N4 (0.012 s−1) nanocomposites, respectively. The superior catalytic performance of as-prepared catalyst in... 

    Synthesis of BiOI/ZnFe2O4-Metal-Organic Framework and g-C3N4-Based Nanocomposites for Applications in Photocatalysis

    , Article Industrial and Engineering Chemistry Research ; Volume 58, Issue 23 , 2019 , Pages 9806-9818 ; 08885885 (ISSN) Khasevani, S. G ; Gholami, M. R ; Sharif University of Technology
    American Chemical Society  2019
    A novel binary BiOI/ZnFe2O4 (BZ) with p-n heterojunction based on the different metal-organic framework (MOF) MIL-88B(Fe) and graphite carbon nitride (g-C3N4) as substrates has been designed. As-prepared ternary nanocomposites have been first obtained via a simple hydrothermal system and subsequently deposited onto the MOF and g-C3N4 substrates. The photoactivity of the ternary nanocomposites was evaluated by organic pollutants degradation under LED light. These characterization results indicated that BiOI as a p-type semiconductor was well deposited on the surface of ZnFe2O4 (n-type semiconductors). The p-n heterojunction photocatalyst (BZ) improved the valence band potential of ZnFe2O4 and... 

    Novel MIL-88A/g-C 3 N 4 nanocomposites: Fabrication, characterization and application as a photocatalyst

    , Article Inorganic Chemistry Communications ; Volume 102 , 2019 , Pages 221-228 ; 13877003 (ISSN) Gholizadeh Khasevani, S ; Gholami, M. R ; Sharif University of Technology
    Elsevier B.V  2019
    The nanocomposite of g-C 3 N 4 supported by MIL-88A has been prepared via a facile hydrothermal method. The photocatalytic performance of as-prepared composite (MIL-88A/g-C 3 N 4 ) was examined by the degradation of the Methylene Blue (MB) solution under visible light. The characterization test illustrated that the MIL-88A particles were successfully dispersed on the surface of g-C 3 N 4 structure. Photoactivity results demonstrated that the MIL-88A/g-C 3 N 4 /H 2 O 2 exhibited dramatically visible light photocatalytic performance. Hydroxyl radicals ([rad]OH) are generated by dissociation of H 2 O 2 under visible irradiation can remarkably enhance the degradation rate of MB molecules.... 

    Evaluation of the reaction mechanism for photocatalytic degradation of organic pollutants with MIL-88A/BiOI structure under visible light irradiation

    , Article Research on Chemical Intermediates ; Volume 45, Issue 3 , 2019 , Pages 1341-1356 ; 09226168 (ISSN) Gholizadeh Khasevani, S ; Gholami, M. R ; Sharif University of Technology
    Springer Netherlands  2019
    In this study, we synthesized novel visible light photocatalyst MIL-88A/BiOI using depositing BiOI particles on the surface of a metal–organic framework (MIL-88A). Photocatalytic application of binary composite MIL-88A/BiOI was obtained by discoloration of Methylene Blue (MB) and Acid Blue 92 (AB92) in aqueous solution under visible light source. The photodegradation experiments for treating organic dyes show that the MIL-88A/BiOI heterojunction structure possess a higher rate for decomposition of dyes due to the decreased aggregation of the BiOI nanoparticles, effective charge carrier separation and the synergistic effect between MIL-88A and BiOI samples as a heterojunction. Also, the... 

    Preparation of Titania based solid strong acid and study of its catalytic activity in esterification of Phthalic anhydride and Sebacic acid

    , Article Materials Letters ; Volume 60, Issue 6 , 2006 , Pages 715-719 ; 0167577X (ISSN) Khodadadi Moghaddam, M ; Gholami, M. R ; Sharif University of Technology
    Esterification of Phthalic anhydride with 2-Octanol and Sebacic acid with Ethanol has been studied in the presence of Sulfated Titania. This study showed that Sulfated Titania has strong catalytic effect on esterification reactions. The effect of some factors such as reaction temperature, molar ratio of acid to alcohol, amount of catalyst used, reaction time, calcination temperature, drying temperature and calcination atmosphere has been investigated. Equilibrium composition achieved in 80 min for Diethyl Sebacate and 20 min for Dioctyl Phthalate in various conditions. © 2005 Elsevier B.V. All rights reserved  

    Substituent effects on the gas phase reactivity of alkyl allyl sulfides, a theoretical study

    , Article Journal of Molecular Structure: THEOCHEM ; Volume 759, Issue 1-3 , 2006 , Pages 11-15 ; 01661280 (ISSN) Izadyar, M ; Gholami, M. R ; Sharif University of Technology
    The potential energy surface of the reaction C3H 5SCH2X→C3H6+XCH=S was studied for the various X substitutions (X=CH3, H, Cl, F) at the high level of the theory (G3MP2 method) using the 6-31G(d) basis set. It was demonstrated that CH3, H, Cl and F substitution, respectively, accelerates the reaction (This order for the substitutions will be called X=CH3-to-F throughout this paper). Barrier height changes from ΔE≠=167. 76 to 148.63 kJ mol-1, because of the electronic effects introduced upon the substitution. It was shown that the X=CH3-to-F substitution in the C6-position posses two types of contribution to the calculated energy barriers and bond lengths at the transition state (TS). First,... 

    Synthesis of CuCo2O4/BiVO4composites as promise and efficient catalysts for 4-nitrophenol reduction in water: Experimental and theoretical study

    , Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 4 , 2021 ; 22133437 (ISSN) Mirzaee Valadi, F ; Gholami, M. R ; Sharif University of Technology
    Elsevier Ltd  2021
    This study investigates the synthesis of CuCo2O4, BiVO4, and CuCo2O4/BiVO4 nanocomposite by the solvothermal method. The Physico-chemical properties of the samples were verified through Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Transmission Electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET). Evaluation of catalytic efficiency of the synthesized samples were done in promoting the 4-Nitrophenol reduction to 4-Aminophenol in the existence of high amount of sodium borohydride (NaBH4) as a reducing agent, and the progress of the catalytic reaction was monitored... 

    Solute-solvent interaction effects on second-order rate constants of reaction between 1-chloro-2,4-dinitrobenzene and aniline in alcohol-water mixtures

    , Article International Journal of Chemical Kinetics ; Volume 37, Issue 2 , 2005 , Pages 90-97 ; 05388066 (ISSN) Harati, M ; Gholami, M. R ; Sharif University of Technology
    The second-order rate coefficients for aromatic nucleophilic substitution reaction between 1-chloro-2,4-dinitrobenzene and aniline have been measured in aqueous solutions of ethanol and methanol at 25°C. The plots of rate constants versus mole fraction of water show a maximum in all-aqueous solutions. The effect of four empirical solvent parameters including hydrogen bond donor acidity (α), dipolarity/polarizability (π*). normalized polarity (ETN), and solvophobicity (Sp) has been investigated. This investigation has been carried out by means of simple and multiple regression models A dual-parameter equation of log k2 versus Sp and α was obtained in all-aqueous solutions (n = 41, r = 0.962,...