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    A facile one-pot, four-component synthesis of (Z)-isomer of rhodanine-oxindole derivatives under environmentally benevolent conditions

    , Article Synthetic Communications ; Volume 52, Issue 2 , 2022 , Pages 175-184 ; 00397911 (ISSN) Moghaddam, F. M ; Aghamiri, B ; Jalalinik, M ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    Abstract
    Herein, an efficient and sustainable one-pot, four-component access to rhodanine-oxindole derivatives is achieved by a reaction between primary amines, carbon disulfide, ethyl chloroacetate, and cyano-substituted alkenyl oxindoles. The reaction was conducted without any harsh conditions as well as exhausting workup in polyethylene glycol (PEG) as a green solvent at room temperature and delivered rhodanine-oxindole products in high yield. This publication is the first easy protocol to be reported for the rapid construction of new rhodanine-oxindole derivatives at room temperature without harsh conditions and via multicomponent reaction. © 2021 Taylor & Francis Group, LLC  

    Tissue growth into three-dimensional composite scaffolds with controlled micro-features and nanotopographical surfaces

    , Article Journal of Biomedical Materials Research - Part A ; Volume 101, Issue 10 , 2013 , Pages 2796-2807 ; 15493296 (ISSN) Tamjid, E ; Simchi, A ; Dunlop, J. W. C ; Fratzl, P ; Bagheri, R ; Vossoughi, M ; Sharif University of Technology
    2013
    Abstract
    Controlling topographic features at all length scales is of great importance for the interaction of cells with tissue regenerative materials. We utilized an indirect three-dimensional printing method to fabricate polymeric scaffolds with pre-defined and controlled external and internal architecture that had an interconnected structure with macro- (400-500 μm) and micro- (∼25 μm) porosity. Polycaprolactone (PCL) was used as model system to study the kinetics of tissue growth within porous scaffolds. The surface of the scaffolds was decorated with TiO2 and bioactive glass (BG) nanoparticles to the better match to nanoarchitecture of extracellular matrix (ECM). Micrometric BG particles were... 

    An unbreakable on-line approach towards sol-gel capillary microextraction

    , Article Journal of Chromatography A ; Volume 1218, Issue 26 , 2011 , Pages 3952-3957 ; 00219673 (ISSN) Bagheri, H ; Piri-Moghadam, H ; Es'haghi, A ; Sharif University of Technology
    2011
    Abstract
    In this work a novel unbreakable sol-gel-based in-tube device for on-line solid phase microextraction (SPME) was developed. The inner surface of a copper tube, intended to be used as a high performance liquid chromatography (HPLC) loop, was electrodeposited by metallic Cu followed by the self assembled monolayers (SAM) of 3-(mercaptopropyl) trimethoxysilane (3MPTMOS). Then, poly (ethyleneglycol) (PEG) was chemically bonded to the -OH sites of the SAM already covering the inner surface of the copper loop using sol-gel technology. The homogeneity and the porous surface structure of the SAM and sol-gel coatings were examined using the scanning electron microscopy (SEM) and adsorption/desorption... 

    Supersonic flutter prediction of functionally graded conical shells

    , Article Composite Structures ; Volume 92, Issue 2 , 2010 , Pages 377-386 ; 02638223 (ISSN) Mahmoudkhani, S ; Haddadpour, H ; Navazi, H.M ; Sharif University of Technology
    2010
    Abstract
    Aero-thermoelastic analysis of a simply supported functionally graded truncated conical shell subjected to supersonic air flow is performed to predict the flutter boundaries. The temperature-dependent properties of the FG shell are assumed to be graded through the thickness according to a simple rule of mixture and power-law function of volume fractions of material constituents. Through the thickness steady-state heat conduction is considered for thermal analysis. To perform the stability analysis, the general nonlinear equations of motion are first derived using the classical Love's shell theory and the von Karman-Donnell-type of kinematic nonlinearity together with the linearized... 

    Acoustic resonance scattering from a multilayered cylindrical shell with imperfect bonding

    , Article Ultrasonics ; Volume 49, Issue 8 , 2009 , Pages 682-695 ; 0041624X (ISSN) Rajabi, M ; Hasheminejad, S. M ; Sharif University of Technology
    Abstract
    The method of wave function expansion is adopted to study the three dimensional scattering of a time-harmonic plane progressive sound field obliquely incident upon a multi-layered hollow cylinder with interlaminar bonding imperfection. For the generality of solution, each layer is assumed to be cylindrically orthotropic. An approximate laminate model in the context of the modal state equations with variable coefficients along with the classical T-matrix solution technique is set up for each layer to solve for the unknown modal scattering and transmission coefficients. A linear spring model is used to describe the interlaminar adhesive bonding whose effects are incorporated into the global... 

    Generic extraction medium: From highly polar to non-polar simultaneous determination

    , Article Analytica Chimica Acta ; Volume 1066 , 2019 , Pages 1-12 ; 00032670 (ISSN) Zeinali, S ; Khalilzadeh, M ; Bagheri, H ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    Sample preparation for non-target analysis is challenging due to the difficulty in the extraction of polar and non-polar analytes simultaneously. Most commercial solid sorbents lack the proper comprehensiveness for extraction of analytes with different physiochemical properties. A possible key is the combination of hydrophobic polymer and hydrophilic surface functional groups in solid based extraction methods in order to generate the susceptibility for retaining both polar and non-polar analytes. To pursue this goal, in this study, four polar groups including [sbnd]NH 2 , [sbnd]NO 2 , [sbnd]COOH, and [sbnd]COCH 3 were chemically bound to Amberlite XAD-4 substrate in order to prepare a... 

    Preparation and evaluation of various banana-based biochars together with ultra-high performance liquid chromatography-tandem mass spectrometry for determination of diverse pesticides in fruiting vegetables

    , Article Food Chemistry ; Volume 360 , 2021 ; 03088146 (ISSN) Keikavousi Behbahan, A ; Mahdavi, V ; Roustaei, Z ; Bagheri, H ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Biomass, originates from plant- or animal-based materials with a huge potential to be reused. Here we report a simple, rapid and inexpensive method for preparation of modified biochars derived from the banana peel followed by their applications in pipette-tip micro solid-phase extraction (PT-µSPE). Due to the contribution of various effective parameters on modification of banana peel biochars (BPBs), Taguchi design was used to optimize activation temperature, activation repetition, treatment material and impregnation ratio. Efficiency of the prepared BPBs were studied by extraction of twelve various pesticides, as model analytes with an extended range of log P values (1.4–5.7), followed by... 

    Unveiling the catalytic ability of carbonaceous materials in Fenton-like reaction by controlled-release CaO2 nanoparticles for trichloroethylene degradation

    , Article Journal of Hazardous Materials ; Volume 416 , 2021 ; 03043894 (ISSN) Ali, M ; Tariq, M ; Sun, Y ; Huang, J ; Gu, X ; Ullah, S ; Nawaz, M. A ; Zhou, Z ; Shan, A ; Danish, M ; Lyu, S ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Carbonaceous materials (CMs) have been applied extensively for enhancing the catalytic performance of environmental catalysts, however, the self-catalytic mechanism of CMs for groundwater remediation is rarely investigated. Herein, we unveiled the catalytic ability of various CMs via Fe(III) reduction through polyvinyl alcohol-coated calcium peroxide nanoparticles (PVA@nCP) for trichloroethylene (TCE) removal. Among selected CMs (graphite (G), biochar (BC) and activated carbon (AC)), BC and AC showed enhancement of TCE removal of 89% and 98% via both adsorption and catalytic degradation. BET and SEM analyses showed a higher adsorption capacity of AC (27.8%) than others. The generation of... 

    Unveiling the catalytic ability of carbonaceous materials in Fenton-like reaction by controlled-release CaO2 nanoparticles for trichloroethylene degradation

    , Article Journal of Hazardous Materials ; Volume 416 , 2021 ; 03043894 (ISSN) Ali, M ; Tariq, M ; Sun, Y ; Huang, J ; Gu, X ; Ullah, S ; Nawaz, M. A ; Zhou, Z ; Shan, A ; Danish, M ; Lyu, S ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Carbonaceous materials (CMs) have been applied extensively for enhancing the catalytic performance of environmental catalysts, however, the self-catalytic mechanism of CMs for groundwater remediation is rarely investigated. Herein, we unveiled the catalytic ability of various CMs via Fe(III) reduction through polyvinyl alcohol-coated calcium peroxide nanoparticles (PVA@nCP) for trichloroethylene (TCE) removal. Among selected CMs (graphite (G), biochar (BC) and activated carbon (AC)), BC and AC showed enhancement of TCE removal of 89% and 98% via both adsorption and catalytic degradation. BET and SEM analyses showed a higher adsorption capacity of AC (27.8%) than others. The generation of... 

    A hierarchical machine learning model based on Glioblastoma patients' clinical, biomedical, and image data to analyze their treatment plans

    , Article Computers in Biology and Medicine ; Volume 150 , 2022 ; 00104825 (ISSN) Ershadi, M. M ; Rahimi Rise, Z ; Akhavan Niaki, S. T ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Aim of study: Glioblastoma Multiforme (GBM) is an aggressive brain cancer in adults that kills most patients in the first year due to ineffective treatment. Different clinical, biomedical, and image data features are needed to analyze GBM, increasing complexities. Besides, they lead to weak performances for machine learning models due to ignoring physicians' knowledge. Therefore, this paper proposes a hierarchical model based on Fuzzy C-mean (FCM) clustering, Wrapper feature selection, and twelve classifiers to analyze treatment plans. Methodology/Approach: The proposed method finds the effectiveness of previous and current treatment plans, hierarchically determining the best decision for... 

    An in vitro study of bare and poly(ethylene glycol)-co-fumarate-coated superparamagnetic iron oxide nanoparticles: A new toxicity identification procedure

    , Article Nanotechnology ; Volume 20, Issue 22 , 2009 ; 09574484 (ISSN) Mahmoudi, M ; Simchi, A ; Imani, M ; Milani, A. S ; Stroeve, P ; Sharif University of Technology
    2009
    Abstract
    As the use of superparamagnetic iron oxide nanoparticles (SPION) in biomedical applications increases (e.g. for targeting drug delivery and imaging), patients are likely to be exposed to products containing SPION. Despite their high biomedical importance, toxicity data for SPION are limited to date. The aim of this study is to investigate the cytotoxicity of SPION and its ability to change cell medium components. Bare and poly(ethylene glycol)-co-fumarate (PEGF)-coated SPION with narrow size distributions were synthesized. The particles were prepared by co-precipitation using ferric and ferrous salts with a molar Fe3+/Fe2+ ratio of 2. Dulbecco's modified Eagle's medium (DMEM) and primary... 

    An efficient one-pot synthesis of 1-aminophosphonates

    , Article Synthesis (Germany) ; Volume 55, Issue 1 , Volume 55, Issue 1 , 2022 , Pages 121-130 ; 00397881 (ISSN) Kaboudin, B ; Faghih, S ; Alavi, S ; Naimi Jamal, M. R ; Fattahi, A ; Sharif University of Technology
    Georg Thieme Verlag  2022
    Abstract
    1-Aminophosphonates are valuable compounds with wide range of applications in biological and industry. Various reaction conditions and catalysts have been reported for the synthesis of 1-aminophosphonates via three-component (dialkyl phosphite + aldehyde + amine) or two-component reaction (dialkyl phosphite + imine). Here a solvent-free synthesis of 1-aminophosphonates under very mild reaction conditions is reported. The three-component condensation reactions of dialkyl phosphite, carbonyl compound, and an amine gave 1- aminophosphonates in good to excellent yields under solvent- and catalyst-free conditions at ambient temperature. Hydrophosphorylation of imines in the presence of dialkyl... 

    One-pot synthesis of dispiro[oxindole-3,3′-pyrrolidines] by three-component [3+2] cycloadditions of in situ-generated azomethine ylides with 3-benzylidene-2,3-dihydro-1H-indol-2-ones

    , Article Helvetica Chimica Acta ; Volume 96, Issue 11 , 2013 , Pages 2103-2114 ; 0018019X (ISSN) Matloubia Moghaddam, F ; Kiamehr, M ; Reza Khodabakhshi, M ; Jebeli Javan, M ; Fathi, S ; Villinger, A ; Iaroshenko, V. O ; Langer, P ; Sharif University of Technology
    2013
    Abstract
    An efficient one-pot, three-component synthesis of novel dispiro[oxindole-3,3′-pyrrolidines] by 1,3-dipolar cycloaddition of azomethine ylides, in situ generated by reaction of 1,2-diones with sarcosine and subsequent decarboxylation, with a series of (E)-3-benzylidene-2,3-dihydro- 1H-indol-2-ones is reported. Molecular complexity is generated in only one synthetic step. All reactions proceed with excellent regioselectivity and in good-to-excellent yields. The workup is easy, the reaction times are short, and no catalyst is required. © 2013 Verlag Helvetica Chimica Acta AG, Zürich