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    Combinatorial screening of nanoclay-reinforced hydrogels: a glimpse of the "holy grail" in orthopedic stem cell therapy?

    , Article ACS Applied Materials and Interfaces ; Volume 10, Issue 41 , 2018 , Pages 34924-34941 ; 19448244 (ISSN) Hasany, M ; Thakur, A ; Taebnia, N ; Kadumudi, F. B ; Shahbazi, M. A ; Pierchala, M. K ; Mohanty, S ; Orive, G ; Andresen, T. L ; Foldager, C. B ; Yaghmaei, S ; Arpanaei, A ; Gaharwar, A. K ; Mehrali, M ; Dolatshahi Pirouz, A ; Sharif University of Technology
    American Chemical Society  2018
    Despite the promise of hydrogel-based stem cell therapies in orthopedics, a significant need still exists for the development of injectable microenvironments capable of utilizing the regenerative potential of donor cells. Indeed, the quest for biomaterials that can direct stem cells into bone without the need of external factors has been the "Holy Grail" in orthopedic stem cell therapy for decades. To address this challenge, we have utilized a combinatorial approach to screen over 63 nanoengineered hydrogels made from alginate, hyaluronic acid, and two-dimensional nanoclays. Out of these combinations, we have identified a biomaterial that can promote osteogenesis in the absence of... 

    Synthesis of nZVI-Ni@BC composite as a stable catalyst to activate persulfate: Trichloroethylene degradation and insight mechanism

    , Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 1 , 2021 ; 22133437 (ISSN) Shan, A ; Idrees, A ; Zaman, W. Q ; Abbas, Z ; Ali, M ; Rehman, M. S. U ; Hussain, S ; Danish, M ; Gu, X ; Lyu, S ; Sharif University of Technology
    Elsevier Ltd  2021
    In Fenton-like oxidation processes, the use of biochar (BC) as support material for the nanoscale zero valent iron-nickel (nZVI-Ni) bimetallic particles attained much attention to activate persulfate (PS) for TCE degradation in aqueous medium. In present work, nZVI-Ni@BC particles with nZVI-Ni to BC mass ratio of 1:5 exhibited excellent results (> 99 % ± 0.24) for TCE degradation. The physico-chemical characteristics, surface morphologies, and elemental mapping of the synthesized nZVI-Ni@BC particles investigated through SEM, EDX, TEM, XPS, XRD, BET and FTIR spectroscopy. For the nZVI-Ni@BC-persulfate system, the effects of PS concentration, initial pH, inorganic ions and natural organic... 

    Zeolite encapsulated Ni(II)-Schiff-base complex: A novel size-selective electro-catalyst for the determination of the purity of stevioside

    , Article Talanta ; Volume 108 , April , 2013 , Pages 19-29 ; 00399140 (ISSN) Rashvand Avei, M ; Jafarian, M ; Etezadi, S ; Gobal, F ; Khakali, M ; Rayati, S ; Ghasem Mahjani, M ; Sharif University of Technology
    Ship-in-a-bottle complex of nickel(II) containing the ligand N,N′-bis(2,4-dihydroxyacetophenone)-2,2-dimethylpropandiimine (H 2{salnptn(4-OH)2}) has been synthesized in zeolite Y. The characteristics of the encapsulated complex are identified by the methods of EDX, SEM, XRD, FT-IR and cyclic voltammetry. A catalytic effect in the electrochemical oxidation of glucose, fructose and sucrose, and a blocking effect in stevioside oxidation are demonstrated on the Ni II{salnptn(4-OH)2}-Y/CPE. The effects of some parameters, such as potential scan rate and concentration of carbohydrates are investigated. The rate constants for the catalytic reaction (k′) of carbohydrates are also obtained. The... 

    Synthesis and characterization of bioactive glass/forsterite nanocomposites for bone and dental implants

    , Article Ceramics - Silikaty ; Volume 56, Issue 4 , 2012 , Pages 331-340 ; 08625468 (ISSN) Kamalian, R ; Yazdanpanah, A ; Moztarzadeh, F ; Ravarian, R ; Moztarzadeh, Z ; Tahmasbi, M ; Mozafari, M ; Sharif University of Technology
    In this research, bioactive glass (BG) of the type CaO-P2O 5-SiO2 and nanocrystalline forsterite (NF) bioceramic were successfully synthesized via sol-gel processing method. Heat-treatment process was done to obtain phase-pure nanopowders. After characterization of each sample, the nanocomposite samples were prepared by cold pressing method and sintered at 1000°C. The samples were fully characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) analyses. The average nanocrystallite size was determined using the Debye-Scherrer's formula 19.6 nm. The bioactivity was examined in vitro... 

    Synthesis, characterization, DFT studies and catalytic activities of manganese(ii) complex with 1,4-bis(2,2′:6,2′′-terpyridin- 4′-yl) benzene

    , Article Dalton Transactions ; Volume 41, Issue 39 , Jul , 2012 , Pages 12282-12288 ; 14779226 (ISSN) Najafpour, M. M ; Hillier, W ; Shamkhali, A. N ; Amini, M ; Beckmann, K ; Jagličić, Z ; Jagodič, M ; Strauch, P ; Moghaddam, A. N ; Beretta, G ; Bagherzadeh, M ; Sharif University of Technology
    A new di-manganese complex with "back-to-back" 1,4-bis(2,2′:6,2′′-terpyridin-4′-yl) benzene ligation has been synthesized and characterised by a variety of techniques. The back-to-back ligation presents a novel new mononuclear manganese catalytic centre that functions as a heterogeneous catalysis for the evolution of oxygen in the presence of an exogenous oxidant. We discuss the synthesis and spectroscopic characterizations of this complex and propose a mechanism for oxygen evolution activity of the compound in the presence of oxone. The di-manganese complex also shows efficient and selective catalytic oxidation of sulfides in the presence of H2O2. Density functional theory calculations were... 

    Characterisation of nanocrystalline sulfated titania modified with transition metals and aluminum as solid acids for esterification

    , Article Progress in Reaction Kinetics and Mechanism ; Volume 41, Issue 1 , 2016 , Pages 57-66 ; 14686783 (ISSN) Rahman Setayesh, S ; Abolhasani, E ; Ghasemi, S ; Sharif University of Technology
    Science Reviews 2000 Ltd  2016
    TiO2, transition metal (Cr, Mn, Fe, Co, Ni, Cu, and Zn)- and aluminum-doped TiO2 nanoparticles were prepared by the sol-gel technique. The sulfated catalysts were prepared by the impregnation method with H2SO4 solution. The catalysts were characterised by X-ray diffraction (XRD), BET surface area measurement, diffuse reflectance spectroscopy (DRS), and Fourier transform infrared (FTIR) techniques. The sulfate content of the metal-incorporated samples was considerably higher than for SO4 2-/TiO2. The metal doping brought about a considerable reduction in the extent of sulfate loss from the catalyst surface due to the wide dispersion on the surface. The SO4 2-/TiO2 and SO4 2-/M/TiO2... 

    Ugi four-component assembly process: An efficient approach for one-pot multifunctionalization of nanographene oxide in water and its application in lipase immobilization

    , Article Chemistry of Materials ; Volume 28, Issue 9 , 2016 , Pages 3004-3016 ; 08974756 (ISSN) Rezaei, A ; Akhavan, O ; Hashemi, E ; Shamsara, M ; Sharif University of Technology
    American Chemical Society  2016
    Graphene-based materials are revealing the leading edge of advanced technology for their exceptional physical and chemical properties. Chemical manipulation on graphene surface to tailor its unique properties and modify atomic structures is being actively pursued. Therefore, the discovery of robust and general protocols to anchor active functionality on graphene basal plane is still of great interest. Multicomponent reactions promise an enormous level of interest due to addressing both diversity and complexity in combinatorial synthesis, in which more than two starting compounds react to form a product derived from entire inputs. In this article, we present the first covalent... 

    Fouling control mechanism by optimum ozone addition in submerged membrane bioreactors treating synthetic wastewater

    , Article Journal of Environmental Chemical Engineering ; Volume 6, Issue 6 , 2018 , Pages 7294-7301 ; 22133437 (ISSN) Mashayekhi, F ; Hazrati, H ; Shayegan, J ; Sharif University of Technology
    In this paper, the effect of ozone on membrane fouling of membrane bioreactor (MBR) systems was investigated. Sludge specification such as soluble microbial product (SMP), extracellular polymeric substance (EPS), viscosity, particle size distribution (PSD), microscopic observations and sludge volume index (SVI) in presence of ozone were determined. Further, EPS, Fourier-transform infrared (FTIR) analysis, excitation-emission matrix (EEM) fluorescence spectroscopy, and gel permission chromatography (GPC) are considered to determine cake layer characteristics. The results indicated COD removal did not show significant difference with ozonation. Ozone also increases the particle size and... 

    Gold-Decorated 3D 2,6-diaminopyridine network: a robust catalyst for the bromination of aromatic compounds

    , Article Industrial and Engineering Chemistry Research ; Volume 57, Issue 37 , 2018 , Pages 12314-12322 ; 08885885 (ISSN) Pourjavadi, A ; Keshavarzi, N ; Hosseini, S. H ; Matloubi Moghaddam, F ; Sharif University of Technology
    American Chemical Society  2018
    This article reports the synthesis of a magnetic heterogeneous catalyst through the decoration of gold ions onto the cross-linked polymeric nanocomposite from 2,6-diaminopyridine. The activity of the resulting catalyst was then evaluated in the bromination of aromatic compounds. The nitrogen rich support showed a high affinity to gold ions, and the measured content of Au was 0.76 mmol g-1. The structure of the catalyst was fully characterized by using Fourier-transform infrared spectroscopy, thermogravimetric analysis, atomic absorption spectroscopy, transmission electron microscopy, scanning electron microscope, energy-dispersive X-ray spectroscopy, Brunauer-Emmett-Teller surface area... 

    Iron‑vanadium oxysulfide nanostructures as novel electrode materials for supercapacitor applications

    , Article Journal of Electroanalytical Chemistry ; Volume 818 , 2018 , Pages 157-167 ; 15726657 (ISSN) Asen, P ; Shahrokhian, S ; Iraji Zad, Azam ; Sharif University of Technology
    Elsevier B.V  2018
    Iron‑vanadium oxysulfide (Fe-VO-S) nanostructures with different Fe:VO atomic ratios are synthesized by a facile and low cost electrochemical deposition method. The synthesis of the various samples is confirmed by the physicochemical characterizations such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). For different Fe-VO-S nanostructures, the correlation between the physicochemical and the electrochemical properties is investigated. It is found that the Fe:VO atomic ratio has an important effect on the structure and size of the resulted particles.... 

    A study of structural, magnetic and various dielectric parameters of Ca-Substituted W-Type hexaferrites for applications at 1–6 GHz frequencies

    , Article Journal of Electronic Materials ; Volume 48, Issue 11 , 2019 , Pages 7149-7161 ; 03615235 (ISSN) ur Rehman, A ; Shaukat, S. F ; Akhtar, M. N ; Ahmad, M ; Sharif University of Technology
    Springer New York LLC  2019
    Single phase Ca-substituted W-type hexaferrites Sr1-xCaxZn2Fe16O27(x = 0.00(0.25)1.00) have successfully been synthesized by using sol–gel self-combustion at 1300°C. These hexaferrites are investigated by x-ray difrractometry (XRD), scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transform infrared spectroscopy, vibrating sample magnetometry, and vector network analysis. XRD analysis confirms the formation of a single W-type hexaferrites phase. The DC electrical resistivity increases with incrementing Ca contents. The morphology of all the hexaferrites shows hexagonal platelet-like structure. The prepared ferrites depict soft magnetic nature with high saturation... 

    An electrochemical sensing platform based on nitrogen-doped hollow carbon spheres for sensitive and selective isoprenaline detection

    , Article Journal of Electroanalytical Chemistry ; Volume 847 , 2019 ; 15726657 (ISSN) Shahrokhian, S ; Panahi, S ; Salimian, R ; Sharif University of Technology
    Elsevier B.V  2019
    In this work, uniform and monodisperse hollow carbon spheres (HCSs) are synthesized through two different processes using polydopamine (PDA), as a carbon precursor, and silica core as a template, under the modified Stöber condition. The surface morphology of the synthesized structures is characterized by means of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Fourier-transform infrared spectroscopy (FT-IR). In the next step, the electrochemical behavior of isoprenaline (ISPN) is investigated by using glassy carbon electrode modified with a thin film of the synthesized hollow carbon spheres. The electrochemical characterization of the modified electrodes is... 

    Polyphosphate-reduced graphene oxide on Ni foam as a binder free electrode for fabrication of high performance supercapacitor

    , Article Electrochimica Acta ; Volume 296 , 2019 , Pages 130-141 ; 00134686 (ISSN) Talebi, M ; Asen, P ; Shahrokhian, S ; Ahadian, M. M ; Sharif University of Technology
    Elsevier Ltd  2019
    Polyphosphate reduced graphene oxide on Ni foam (PPO-RGO/NF) is synthesized by varying weight ratios of Na5P3O10 (PO): graphene oxide (GO) with a simple, scalable and low cost method through freeze-drying of the PO-GO/NF followed by thermal treatment of the prepared electrodes. The resulting samples are characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), Brunauer-Emmett-Teller (BET), and raman spectroscopy methods. The results show that the weight ratio of PO:GO, considerably affect the... 

    Pectic acid–graphene oxide nanocomposite as an adsorbent in vortex-assisted dispersive solid-phase extraction for preconcentration of copper ion followed by flame atomic absorption spectrometry

    , Article Polymer Bulletin ; Volume 77, Issue 6 , 2020 , Pages 2821-2836 Eftekhari, A ; Shakerian, M ; Majeed, H. J ; Eftekhari, M ; Rezazadeh, N ; Sharif University of Technology
    Springer  2020
    An efficient, green, novel and rapid vortex-assisted dispersive solid-phase extraction (VADSPE) technique was used for the preconcentration and determination of trace levels of Cu2+ followed by flame atomic absorption spectrometry. Graphene oxide (GO) was synthesized from graphite and then modified by pectic acid (poly-d-galacturonic acid, PA) to synthesize the pectic acid–graphene oxide (PA-GO) nanocomposite. The Fourier transform infrared spectrophotometry, field emission scanning electron microcopy, energy-dispersive X-ray spectroscopy and X-ray diffraction analysis were used to characterize the synthesized GO-PA nanocomposite. By using VADSPE technique, PA-GO was used as an adsorbent for... 

    Development of a quartz crystal microbalance biodetector based on cellulose nanofibrils (CNFs) for glycine

    , Article Journal of Materials Science: Materials in Electronics ; Volume 31, Issue 20 , 2020 , Pages 17451-17460 Hosseini, M. S ; Iraji zad, A ; Vossoughi, M ; Kalantarian, A ; Sharif University of Technology
    Springer  2020
    The performance of a quartz crystal microbalance (QCM) used as a sensor/detector relies on the performance and quality of the film coated onto the quartz crystal sensor. This study focuses on the sensor coating preparation for the detection of glycine. Cellulose nanofibrils (CNFs), natural polymers, were coated on a quartz crystal (QC) surface by a spin-coating method. The prepared CNF-coated QC was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), cyclic voltammetry (CV), Fourier transform infrared spectrophotometry-attenuated total reflectance (FTIR-ATR), Raman spectroscopy, and water contact angle (WCA). The stable and fully covered QCs without further... 

    In situ synthesis of quasi-needle-like bimetallic organic frameworks on highly porous graphene scaffolds for efficient electrocatalytic water oxidation

    , Article Chemical Communications ; Volume 56, Issue 21 , 2020 , Pages 3135-3138 Nourmohammadi Khiarak, B ; Hasanzadeh, M ; Mojaddami, M ; Shahriyar Far, H ; Simchi, A ; Sharif University of Technology
    Royal Society of Chemistry  2020
    We present enhanced electrocatalytic activity of three-dimensional graphene scaffolds by decoration with one-dimensional CoxNi1-x MOF nanostructures (0 ≤ x ≤ 1). The decreased overpotential and fast kinetics of the oxygen evolution reaction as compared with the existing materials are shown. The developed bimetallic MOF/3DG composites have great potential to be used in electrocatalytic water oxidation. This journal is © The Royal Society of Chemistry  

    A new insight to the assessment of asphaltene characterization by using fortier transformed infrared spectroscopy

    , Article Journal of Petroleum Science and Engineering ; Volume 205 , 2021 ; 09204105 (ISSN) Taherian, Z ; Saeedi Dehaghani, A ; Ayatollahi, S ; Kharrat, R ; Sharif University of Technology
    Elsevier B.V  2021
    This research aims to present asphaltene fraction of oil by FTIR spectrum technique. For this purpose, three different oil samples with various SARA contents and almost identical API degrees were utilized in this research. Two asphaltenic oil samples were referred to as ‘A’ and ‘B’, and the aliphatic oil sample was named as ‘C’. First of all, the asphaltene fraction was extracted through the IP-143 test. The possible chemical bonds and functional groups were identified through NMR tests. Then, the FTIR spectrums of the oil samples and the extracted corresponding asphaltene fractions were taken. The interpretations were used to find the functional groups in the FTIR of the oil samples that... 

    External parameter orthogonalization-support vector machine for processing of attenuated total reflectance-mid-infrared spectra: A solution for saffron authenticity problem

    , Article Analytica Chimica Acta ; Volume 1154 , 2021 ; 00032670 (ISSN) Amirvaresi, A ; Parastar, H ; Sharif University of Technology
    Elsevier B.V  2021
    In the present work, a new approach based on external parameter orthogonalization combined with support vector machine (EPO-SVM) is proposed for processing of attenuated total reflectance-Fourier transform mid-infrared (ATR-FT-MIR) spectra with the goal of solving authentication problem in saffron, the most expensive spice in the world. First, one-hundred authentic saffron samples are clustered by principal component analysis (PCA) with EPO as the best preprocessing strategy. Then, EPO-SVM is used for the detection of four commonly used plant-derived adulterants (i.e. safflower, calendula, rubia, and style) in binary mixtures (saffron and each of plant adulterants) and its performance is... 

    Preparation of new MOF-808/chitosan composite for Cr(VI) adsorption from aqueous solution: Experimental and DFT study

    , Article Carbohydrate Polymers ; Volume 288 , 2022 ; 01448617 (ISSN) Mirzaee Valadi, F ; Shahsavari, S ; Akbarzadeh, E ; Gholami, M. R ; Sharif University of Technology
    Elsevier Ltd  2022
    In this study, a series of Zirconium-based MOF and chitosan composites (MOF-808/chitosan) were synthesized as efficient adsorbent for Cr(VI) ions elimination from aqueous solution. MOF-808/chitosan structure and morphology was characterized by FE-SEM, EDX, XRD, BET, zeta potential analysis, FT-IR, XPS techniques. The kinetic studies ascertained that Cr(VI) adsorption over MOF-808/chitosan followed pseudo-second-order kinetic model. The adsorption isotherms fitted the Langmuir isotherm model, implying on homogeneously adsorption of Cr(VI) on the surface of MOF-808/chitosan. According to the Langmuir model, the maximum capacity was obtained to be 320.0 mg/g at pH 5. Thermodynamic investigation... 

    Synthesizing and staining manganese oxide nanoparticles for cytotoxicity and cellular uptake investigation

    , Article Biochimica et Biophysica Acta - General Subjects ; Vol. 1840, Issue. 1 , 2014 , pp. 428-433 ; ISSN: 03044165 Omid, H ; Oghabian, M. A ; Ahmadi, R ; Shahbazi, N ; Hosseini, H. R. M ; Shanehsazzadeh, S ; Zangeneh, R. N ; Sharif University of Technology
    Background For decades, contrast agents have been used to reduce longitudinal (T1) or transverse (T2) relaxation times. High toxicity of gadolinium-based contrast agents leads researchers to new T1 contrast agents. Manganese oxide (MnO) nanoparticle (NP) with the lower peril and good enough signal change ability has been offered as a new possibility for magnetic resonance imaging (MRI). Methods The synthesized NPs were investigated for physicochemical and biological properties by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscope, dynamic light scattering (DLS), inductively coupled plasma, enzyme-linked immunosorbent assay, and 3 T magnetic resonance...