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    Catalytic wet peroxide oxidation of phenol in a new two-impinging-jets reactor

    , Article Industrial and Engineering Chemistry Research ; Volume 48, Issue 23 , 2009 , Pages 10619-10626 ; 08885885 (ISSN) Dehkordi, A. M ; Ebrahimi, A. A ; Sharif University of Technology
    Abstract
    The catalytic wet peroxide oxidation (CWPO) of phenol with activated carbon (AC) as the catalyst has been successfully tested in a novel type of two-impinging-jets reactor (TIJR). The TIJR is characterized by a high-intensity reaction chamber, which is separated by a perforated plate from other parts of the reactor. The perforated plate was used as a filter to keep the catalyst particles within the reaction chamber. The influences of various operating and design parameters such as jet Reynolds number, feed flow rate, internozzle distance, and the jet diameter on the performance capability of the TIJR were investigated. As a result of the impinging process, turbulence, complex trajectory 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... 

    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... 

    Advancement in Fenton-like reactions using PVA coated calcium peroxide/FeS system: Pivotal role of sulfide ion in regenerating the Fe(II) ions and improving trichloroethylene degradation

    , Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 1 , 2021 ; 22133437 (ISSN) Ali, M ; Zhang, X ; Idrees, A ; Tariq, M ; Danish, M ; Farooq, U ; Shan, A ; Jiang, X ; Huang, J ; Lyu, S ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    This study demonstrated the prolonged benefits of polyvinyl-coated calcium peroxide (PVA@CP) in Fe(II)/nFeS mediated Fenton-like reaction. PVA@CP was prepared by a coating of PVA on calcium peroxide (CP) and synthesized nano-sized iron sulfide (nFeS) was characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopy (EDS) elemental mapping, X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma optical emission spectroscopy (ICP-OES) and Fourier transmission infrared (FTIR) techniques. Trichloroethylene (TCE) degradation in various oxic environments (H2O2, CP, or... 

    Advancement in Fenton-like reactions using PVA coated calcium peroxide/FeS system: Pivotal role of sulfide ion in regenerating the Fe(II) ions and improving trichloroethylene degradation

    , Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 1 , 2021 ; 22133437 (ISSN) Ali, M ; Zhang, X ; Idrees, A ; Tariq, M ; Danish, M ; Farooq, U ; Shan, A ; Jiang, X ; Huang, J ; Lyu, S ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    This study demonstrated the prolonged benefits of polyvinyl-coated calcium peroxide (PVA@CP) in Fe(II)/nFeS mediated Fenton-like reaction. PVA@CP was prepared by a coating of PVA on calcium peroxide (CP) and synthesized nano-sized iron sulfide (nFeS) was characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) with energy dispersive spectroscopy (EDS) elemental mapping, X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma optical emission spectroscopy (ICP-OES) and Fourier transmission infrared (FTIR) techniques. Trichloroethylene (TCE) degradation in various oxic environments (H2O2, CP, or... 

    Antioxidant Production from Rice Bran and Optimization of the Process

    , M.Sc. Thesis Sharif University of Technology Arab, Fatemeh (Author) ; Alemzadeh, Iran (Supervisor) ; Maghsoudi, Vida (Supervisor)
    Abstract
    An antioxidant is a molecule capable of preventing the oxidation of other molecules and neutralizing free radicals. Free radicals are the root cause for many human diseases.Rice bran is one of the most important co-products in the rice milling.In this research antioxidant activity of two Iranian rice bran varieties Fajr and Tarem, extracted by three different solvents (methanol, ethanol and ethyl acetate),determined at different time of extraction by measurement of total phenolic content, free radical scavenging, inhabitation of linoleic acid peroxidation and reducing power. The methanolic extract of Fajr rice bran produced strong results in antioxidant activity. The amount of Total... 

    The comparision of Coprinus cinereus peroxidase enzyme and TiO 2 catalyst for phenol removal

    , Article Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering ; Volume 48, Issue 3 , 2013 , Pages 300-307 ; 10934529 (ISSN) Sarkhanpour, R ; Tavakoli, O ; Sarrafzadeh, M. H ; Kariminia, H. R ; Sharif University of Technology
    2013
    Abstract
    This article investigates phenol removal from an aqueous solution by using enzymatic and photocatalytic methods and the efficiency of these methods has been compared. In enzymatic and photocatalytic methods, Coprinus cinereus, peroxidase enzyme and commercial TiO2 powders (Degussa P-25) in aqueous suspension were used, respectively, in ambient temperature. The effects of different operating parameters such as duration of process, catalyst dosage or enzyme concentration, pH of the solution, initial phenol concentration and H2O2 concentration on both processes were examined. In enzymatic method, efficiency of degradation reached 100% within 5min, while in the photocatalytic method, the... 

    Localized surface plasmon resonance sensor for simultaneous kinetic determination of peroxyacetic acid and hydrogen peroxide

    , Article Analytica Chimica Acta ; Volume 762 , 2013 , Pages 87-93 ; 00032670 (ISSN) Tashkhourian, J ; Hormozi Nezhad, M. R ; Khodaveisi, J ; Dashti, R ; Sharif University of Technology
    2013
    Abstract
    A new sensor for simultaneous determination of peroxyacetic acid and hydrogen peroxide using silver nanoparticles (Ag-NPs) as a chromogenic reagent is introduced. The silver nanoparticles have the catalytic ability for the decomposition of peroxyacetic acid and hydrogen peroxide; then the decomposition of them induces the degradation of silver nanoparticles. Hence, a remarkable change in the localized surface plasmon resonance absorbance strength could be observed. Spectra-kinetic approach and artificial neural network was applied for the simultaneous determination of peroxyacetic acid and hydrogen peroxide. Linear calibration graphs were obtained in the concentration range of (8.20×10-5 to... 

    Determination of antioxidant component and activity of rice bran extract

    , Article Scientia Iranica ; Volume 18, Issue 6 , December , 2011 , Pages 1402-1406 ; 10263098 (ISSN) Arab, F ; Alemzadeh, I ; Maghsoudi, V ; Sharif University of Technology
    2011
    Abstract
    Rice bran is one of the most important co-products in the rice milling. In this research, antioxidant activity of two Iranian rice bran varieties, Fajr and Tarem, extracted by three different solvents (methanol, ethanol and ethyl acetate) was evaluated. The order of antioxidant activity was evaluated by measurement of total phenolic content, antioxidant activity in linoleic acid system, reducing power and scavenging capacity by DPPH radical. The methanolic extract of Fajr rice bran showed a total phenolic content of 3.31 mg Gallic acid/gr rice bran and a DPPH free radical-scavenging activity of 93.91%, achieved at 50 mg/ml concentration, and a percent inhibition of linoleic acid peroxidation... 

    Adsorption and dissociation of hydrogen peroxide on small Pd xM3-x (M = Pt, Cu; X = 1-3) clusters: A hybrid density functional study

    , Article Molecular Physics ; Volume 109, Issue 14 , May , 2011 , Pages 1797-1804 ; 00268976 (ISSN) Nahali, M ; Gobal, F ; Arab, R ; Sharif University of Technology
    2011
    Abstract
    The adsorption and dissociation of H2O2 on small PdxM3-x (M=Pt, Cu; x = 1-3) clusters is investigated using the B3PW91 hybrid density functional method. Natural bond orbitals are analysed to obtain partial charges on atoms, dipole moments, bond orders, and hybrid orbitals of the PdxM3-x-H2O2 systems. The calculated adsorption energies are in the range of -0.32 to -2.12 eV. Generally, H2O2 adsorbs on top positions through one of its oxygen atoms and only in a few cases reacts with the cluster through both oxygen and hydrogen sides. In the latter case the cluster sites which are negatively charged interact with the hydrogen atoms. Interestingly, on the triplet Pd2Pt cluster, H2O2 dissociates... 

    Effect of formulation factors on the bioactivity of glucose oxidase encapsulated chitosan-alginate microspheres: In vitro investigation and mathematical model prediction

    , Article Chemical Engineering Science ; Volume 125 , March , 2015 , Pages 4-12 ; 00092509 (ISSN) Abdekhodaie, M. J ; Cheng, J ; Wu, X. Y ; Sharif University of Technology
    Elsevier Ltd  2015
    Abstract
    Higher reactive oxygen species (ROS) levels in cancer cells than normal cells have long been recognized, which makes cancer cells more susceptible to excess ROS. Thus oxidation (also called pro-oxidant) therapy has been explored as new cancer therapy regimens. To produce additional ROS, e.g. H2O2 in situ within tumor, we encapsulated glucose oxidase in chitosan-coated alginate-calcium microspheres (GOX-MS) for locoregional treatment and demonstrated its efficacy against cancer cells in vitro and in vivo. Owing to the complex biological functions of ROS, the production rate and amount of H2O2 are critical to achieve therapeutic benefits without causing normal tissue toxicity. This work was... 

    Polymeric ionic liquid nanogel-anchored tungstate anions: A robust catalytic system for oxidation of sulfides to sulfoxides

    , Article New Journal of Chemistry ; Volume 39, Issue 2 , 2015 , Pages 1348-1354 ; 11440546 (ISSN) Pourjavadi, A ; Nazari Chamazkoti, M ; Hosseini, S. H ; Sharif University of Technology
    Abstract
    A new heterogeneous catalytic system was prepared by immobilization of tungstate ions on a cross-linked poly(ionic liquid) nanogel. The solid nanogel was easily synthesized by a surfactant-less method. The resulting catalyst was highly active in selective oxidation of sulfides to sulfoxides by H2O2. The oxidation reactions were successfully performed under solvent-free conditions affording high yields. The catalyst was recycled and reused for several reaction cycles without any significant loss of catalytic activity  

    Mo(vi) complex supported on Fe3O4 nanoparticles: magnetically separable nanocatalysts for selective oxidation of sulfides to sulfoxides

    , Article RSC Advances ; Volume 5, Issue 66 , Jun , 2015 , Pages 53349-53356 ; 20462069 (ISSN) Keypour, H ; Balali, M ; Haghdoost, M. M ; Bagherzadeh, M ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Abstract
    A molybdenum complex, [MoO2Cl2(DMSO)2], was immobilized on amino propyl and Schiff base modified magnetic Fe3O4@SiO2 nanoparticles by covalent linkage. The resulting nanoparticles were used as efficient and recyclable catalysts for the selective oxidation of sulfides to sulfoxides using urea hydrogen peroxide as the oxidant. The complete characterization of catalysts was carried out by means of thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), elemental analysis, FT-IR and Raman microprobe... 

    Characteristics and composition of watermelon seed oil and solvent extraction parameters effects

    , Article JAOCS, Journal of the American Oil Chemists' Society ; Volume 87, Issue 6 , 2010 , Pages 667-671 ; 0003021X (ISSN) Moaddabdoost Baboli, Z ; Safe Kordi, A. A ; Sharif University of Technology
    2010
    Abstract
    Watermelon seed oil characteristics were evaluated to determine whether this oil could be exploited as an edible oil. Hexane extraction of watermelon seeds produced yields of 50% (w/w) oil. The refractive index, saponification and iodine value were 1.4712 (at 25 °C), 200 mg KOH/g and 156 g I/100 g, respectively. The acid and peroxide values were 2.4 mg KOH/g and 3.24 mequiv/kg, respectively. The induction time of the oil was also 5.14 h at 110 °C, which was measured for the first time. Total unsaturation contents of the oil was 81.6%, with linoleic acid (18:2) being the dominant fatty acid (68.3%). Considering that the watermelon seed oil was highly unsaturated, the relatively high induction... 

    Catalytic behavior of an iron(III) complex containing an N,O-type bidentate oxazoline ligand for selective oxidation of sulfides

    , Article Transition Metal Chemistry ; Volume 41, Issue 1 , 2016 , Pages 97-105 ; 03404285 (ISSN) Amini, M ; Khaksar, M ; Arab, A ; Masoomi Jahandizi, R ; Bagherzadeh, M ; Boghaei, D. M ; Ellern, A ; Keith Woo, L ; Sharif University of Technology
    Springer International Publishing 
    Abstract
    The reaction of Fe(acac)3 and 2-(2′-hydroxyphenyl)oxazoline (Hphox) as a bidentate O,N donor ligand afforded a six-coordinated iron(III) complex [Fe(phox)2(acac)] with distorted octahedral configuration. The complex was isolated as an air-stable crystalline solid and characterized by elemental analysis, FTIR, solution electrical conductivity, and by single-crystal X-ray structure analysis. The structure, electronic properties, and vibrational normal modes of the complex were investigated by DFT. The use of this complex as a catalyst for the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide as the primary oxidant was investigated. The catalyst shows very... 

    Kinetic study and growth behavior of template-based electrodeposited platinum nanotubes controlled by overpotential

    , Article Materials Chemistry and Physics ; Volume 187 , 2017 , Pages 141-148 ; 02540584 (ISSN) Yousefi, E ; Dolati, A ; Imanieh, I ; Yashiro, H ; Kure-Chu, S. Z ; Sharif University of Technology
    Elsevier Ltd  2017
    Abstract
    Platinum nanotubes (PtNTs) are fabricated by potentiostatic electrodeposition at various overpotentials (−200 up to −400 mV versus SCE) in polycarbonate templates (PCTs) with pore diameter of 200 nm in a solution containing 5 mM H2PtCl6 and 0.1 M H2SO4. The synthesized PtNTs are characterized by field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The electrochemical growth mechanism within nanoscopic pores and the relationship between morphological variations and kinetic parameters are investigated for the first time. It is shown that more porous structure of nanotubes forms at high overpotentials possibly due to preferably nucleation. The... 

    Nano mesoporous silica for cancer treatment: ROS-responsive and redox-responsive carriers

    , Article Journal of Drug Delivery Science and Technology ; Volume 57 , 2020 Bahrami, F ; Abdekhodaie, M. J ; Behroozi, F ; Mehrvar, M ; Sharif University of Technology
    Editions de Sante  2020
    Abstract
    Reactive oxygen species ROS and redox agents are two features of cancer medium, which could be used through responsive drug delivery systems for cancer treatment. Furthermore, mesoporous silica nanoparticles (MSNs) have special characteristics to use them in ROS-responsive and redox-responsive carriers. To shed light on this issue, we propose two drug delivery systems: 1) responsive to hydrogen peroxide (a ROS component) and 2) responsive to dithiothreitol (a redox agent). The proposed carriers are composed of 4 parts: MSNs, responsive agent (selenocystine for ROS-responsive and dithiodipropionic for the redox-responsive carrier), hyaluronic acid as the coating and targeting agent, and the... 

    Catalytic oxidation of sulfides to sulfoxide using manganese(III) complexes with bidentate O,N-donor oxazoline ligand and UHP oxidizing agent

    , Article Catalysis Communications ; Volume 10, Issue 2 , 2008 , Pages 196-200 ; 15667367 (ISSN) Bagherzadeh, M ; Latifi, R ; Tahsini, L ; Amini, M ; Sharif University of Technology
    2008
    Abstract
    The efficient catalytic systems were investigated for the oxidation of various sulfide by manganese(III)-oxazoline complexes, [Mn(phox)2(MeOH)2]ClO4 and Mn(phox)3 (Hphox = 2-(2′-hydroxyphenyl)oxazoline). These complexes were found efficient catalysts for the oxidation of sulfides with urea hydrogen peroxide (UHP) in short reaction times (5 min) and under mild condition. Sulfoxides were obtained as the main products together with variable amounts of sulfones. The efficiency of the catalytic system was strongly influenced by the nature of solvents and axial ligands so the best yields were achieved in a mixture of methanol: dichloromethane and in the presence of imidazole as co-catalyst. © 2008... 

    Density functional theory studies of oxygen and carbonate binding to a dicopper patellamide complex

    , Article Journal of Inorganic Biochemistry ; Volume 102, Issue 12 , 2008 , Pages 2171-2178 ; 01620134 (ISSN) Latifi, R ; Bagherzadeh, M ; Milne, B. F ; Jaspars, M ; de Visser, S. P ; Sharif University of Technology
    2008
    Abstract
    In this work we present results of density functional theory (DFT) calculations on dicopper patellamides and their affinity for molecular oxygen and carbonate. Patellamides are cyclic octapeptides that are produced by a cyanobacterium, and may show promise as therapeutics. Thus, carbonate binding to a dicopper patellamide center gives a stable cyclic octapeptide with a twist of almost 90°. The system exists in close-lying open-shell singlet and triplet spin states with two unpaired electrons in orthogonal σ* orbitals on each metal center. Subsequently, we replaced carbonate with dioxygen and found a stable Cu2(μ-O)2 diamond shaped patellamide core. In this structure the original dioxygen... 

    An innovative, highly stable Ag/ZIF-67@GO nanocomposite with exceptional peroxymonosulfate (PMS) activation efficacy, for the destruction of chemical and microbiological contaminants under visible light

    , Article Journal of Hazardous Materials ; Volume 413 , 2021 ; 03043894 (ISSN) Kohantorabi, M ; Giannakis, S ; Moussavi, G ; Bensimon, M ; Gholami, M. R ; Pulgarin, C ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    In this work, Ag nanoparticles were loaded on ZIF-67 covered by graphene oxide (Ag/ZIF-67@GO), and its catalytic performance was studied for the heterogeneous activation of peroxymonosulfate (PMS) under visible-light. The catalyst surface morphology and structure were analyzed by FT-IR, XRD, XPS, DRS, FE-SEM, EDX, TEM, BET, ICP-AES and TGA analysis. The efficacy of PMS activation by the Ag/ZIF-67@GO under visible light was assessed by phenol degradation and E. coli inactivation. Phenol was completely degraded within 30 min by HO•, SO4•− and O2•− generated through the photocatalytic PMS activation. In addition, total E. coli inactivation was attained in 15 min that confirmed the highly...