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    Erratum: Shock polar investigation in supersonic rarefied gas flows over a circular cylinder (Physics of Fluids (2021) 33 (052006) DOI: 10.1063/5.0050571)

    , Article Physics of Fluids ; Volume 33, Issue 6 , 2021 ; 10706631 (ISSN) Akhlaghi, H ; Roohi, E ; Daliri, A ; Soltani, M. R ; Sharif University of Technology
    American Institute of Physics Inc  2021
    Abstract
    This article was originally published online on 25May 2021 with the third author listed at the wrong affiliation. The affiliations appear correct above. All online versions of the article were corrected on 28 May 2021; the article is correct as it appears in the printed version of the journal. © 2021 American Institute of Physics Inc.. All rights reserved  

    Unique examples of copper(II)/sodium(I) and nickel(II)/sodium(I) Schiff base complexes with bridging bis-bidentate Salen type ligand: Synthesis, crystal structures and antibacterial studies

    , Article Inorganica Chimica Acta ; Volume 445 , 2016 , Pages 124-128 ; 00201693 (ISSN) Mahlooji, N ; Behzad, M ; Amiri Rudbari, H ; Bruno, G ; Ghanbari, B ; Sharif University of Technology
    Elsevier S.A  2016
    Abstract
    Two unique heteronuclear Schiff base complexes of Cu(II), [{Cu(L)Na(ClO4)}2(μ-H2L)] (1) and Ni(II), [{Ni(L)Na(BF4)}2(μ-H2L)] (2) were synthesized and characterized by different spectroscopic methods as well as X-ray crystallography. The Schiff base ligand (H2L) was synthesized from the condensation meso-1,2-diphenyl-1,2-ethylenediamine with 3-methoxysalicylaldehyde. The 3d metal ions in these complexes have been accommodated by the inner N2O2 compartment of the Schiff base ligand, while the O2O′2 outer compartment has accommodated the Na(I) ion (O and O′ denote the phenolic and methoxy oxygen atoms, respectively). Besides, a Schiff base ligand has doubly bridged the M(II)/Na(I) moieties via... 

    Magnetic metal nanoparticles decorated ionic liquid with excellent antibacterial activity

    , Article Journal of Nanostructures ; Volume 10, Issue 3 , 2020 , Pages 613-623 Salari, H ; Karimi Asl, M ; Padervand, M ; Gholami, M. R ; Sharif University of Technology
    University of Kashan  2020
    Abstract
    Fe3O4 magnetic structure was synthesized with co-precipitation method. Surface of magnetic core was modified with hydrophobic BMIM[PF6] ionic liquid. The samples became antibacterial by loading gold, copper and silver nanoparticles and denoted as Fe3O4/IL/X (X=Ag, Au, Cu). X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), thermal gravimetric analysis (TGA), Atomic absorption spectroscopy (AAS), Fourier transform infrared (FTIR) and vibration sample magnetometer (VSM) technics were applied for catalysts characterization, metal concentration analysis and morphology monitoring. Modified nanostructures were used for inactivation of Escherichia coli as... 

    Enhanced antibacterial activity of echinacea angustifolia extract against multidrug-resistant klebsiella pneumoniae through niosome encapsulation

    , Article Nanomaterials ; Volume 11, Issue 6 , 2021 ; 20794991 (ISSN) Moghtaderi, M ; Mirzaie, A ; Zabet, N ; Moammeri, A ; Mansoori Kermani, A ; Akbarzadeh, I ; Eshrati Yeganeh, F ; Chitgarzadeh, A ; Bagheri Kashtali, A ; Ren, Q ; Sharif University of Technology
    MDPI AG  2021
    Abstract
    With the increased occurrence of antibiotic-resistant bacteria, alternatives to classical antibiotics are urgently needed for treatment of various infectious diseases. Medicinal plant extracts are among the promising candidates due to their bioactive components. The aim of this study was to prepare niosome-encapsulated Echinacea angustifolia extract and study its efficacy against multidrug-resistant Klebsiella pneumoniae strains. Encapsulation was first optimized by Design of Experiments, followed by the empirical study. The obtained niosomes were further charac-terized for the size and morphology using dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning... 

    In vitro study: Evaluation of mechanical behavior, corrosion resistance, antibacterial properties and biocompatibility of HAp/TiO2/Ag coating on Ti6Al4V/TiO2 substrate

    , Article Surfaces and Interfaces ; Volume 24 , 2021 ; 24680230 (ISSN) Ahmadi, R ; Asadpourchallou, N ; Koozegar Kaleji, B ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Biocompatibility materials such as Ti6Al4V alloy have many medical applications, but their corrosion resistance and antibacterial properties are low, which limits their medical application. Therefore, to improve these challenges in this study, HAp + 15 wt% TiO2 + 5 wt% Ag nanocomposite coating was applied on Ti6Al4V/TiO2 substrate by sol-gel dip method and sintered at 550 °C. The TiO2 layer was pre-formed on the Ti6Al4V substrate using the gel-sol process. The results showed that the nanocomposite was synthesized correctly, and the particle size was in range of 40–90 nm. The evaluation of the coatings developed showed that TiO2/HAp + 15 wt% TiO2 + 5 wt% Ag coating had higher adhesion... 

    In vitro study: Evaluation of mechanical behavior, corrosion resistance, antibacterial properties and biocompatibility of HAp/TiO2/Ag coating on Ti6Al4V/TiO2 substrate

    , Article Surfaces and Interfaces ; Volume 24 , 2021 ; 24680230 (ISSN) Ahmadi, R ; Asadpourchallou, N ; Koozegar Kaleji, B ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Biocompatibility materials such as Ti6Al4V alloy have many medical applications, but their corrosion resistance and antibacterial properties are low, which limits their medical application. Therefore, to improve these challenges in this study, HAp + 15 wt% TiO2 + 5 wt% Ag nanocomposite coating was applied on Ti6Al4V/TiO2 substrate by sol-gel dip method and sintered at 550 °C. The TiO2 layer was pre-formed on the Ti6Al4V substrate using the gel-sol process. The results showed that the nanocomposite was synthesized correctly, and the particle size was in range of 40–90 nm. The evaluation of the coatings developed showed that TiO2/HAp + 15 wt% TiO2 + 5 wt% Ag coating had higher adhesion... 

    Efficient wound healing by antibacterial property: Advances and trends of hydrogels, hydrogel-metal NP composites and photothermal therapy platforms

    , Article Journal of Drug Delivery Science and Technology ; Volume 73 , 2022 ; 17732247 (ISSN) Ahmadian, Z ; Gheybi, H ; Adeli, M ; Sharif University of Technology
    Editions de Sante  2022
    Abstract
    Bacterial infection is one of the biggest challenges in wound healing and imposes enormous burden on patient and medical system. Moreover, multidrug resistant microorganisms (MDR) limit the usage of therapeutic agents including antibiotics for wound treatment. Hydrogels are three-dimensional networks that have emerged as efficient scaffolds for the treatment of infected wounds. In addition to their intrinsic antibacterial activities, hydrogels are able to load and release therapeutic agents to keep the efficient dose during wound healing process. At the same lines, incorporation of metal nanoparticles (NPs) into hydrogels boosts their antibacterial activity. Moreover, photothermal agents... 

    Synthesis and Antibacterial Activity of TiO2/ZnO Nanocomposite via Sol-Gel Method

    , M.Sc. Thesis Sharif University of Technology Mohammadi, Hanif (Author) ; Ghorbani, Mohammad (Supervisor)
    Abstract
    The synthesis and usage of TiO2/ZnO nanocomposite thin film in antibacterial activity against E-coli were experimented through a systematic research. TiO2/ZnO nanocomposite films can demonstrate different properties like gas sensing, self cleaning and treatment of the broad range of aqueous pollutants when it is exposed to light with wavelengths less than 400 nm. This phenomenon happens because of the photocatalytic reactions in the nanocomposite thin film which cause active species production on the surface of the thin film. The nanocomposite synthesis was based on sol-gel process in atmospheric pressure. In this study titanium dioxide is prepared by sol gel method from titanium... 

    Synthesis of Colloidal Silver Nanoparticles by Microwave Method and Study of its Antibacterial Activity

    , M.Sc. Thesis Sharif University of Technology Abtahi, Nikoo (Author) ; Dolati, Abolghasem (Supervisor)
    Abstract
    Silver nanoparticles are widely used in different industries because of their antibacterial effects. Many synthesis methods were used to obtain silver nanoparticles. In this study the microwave method is used to synthesize nanosilver. This method is easier and faster in comparison to other methods. The effect of precursors’ concentrations, using different solvents, different remaining time in microwave and microwave power were studied. By increasing the reaction time, microwave power and using different solvents, nanosilver particle size varies from 2 nm up to 300nm. The TEM images, size distribution, XRD patterns and UV-visible spectrum are shown. The obtained nanosilver was used to observe... 

    Incredible antibacterial activity of noble metal functionalized magnetic core-zeolitic shell nanostructures

    , Article Materials Science and Engineering C ; Volume 35, Issue 1 , Feb , 2014 , Pages 115-121 Padervand, M. (Mohsen) ; Janatrostami, S ; Karanji, A. K ; Gholami, M. R. (Mohamad Reza) ; Sharif University of Technology
    Abstract
    Functionalized magnetic core-zeolitic shell nanostructures were prepared by hydrothermal and coprecipitation methods. The products were characterized by Vibrating Sample Magnetometer (VSM), X-ray powder diffraction (XRD), Fourier Transform Infrared (FTIR) spectra, nitrogen adsorption-desorption isotherms, and Transmission Electron Microscopy (TEM). The growth of mordenite nanoparticles on the surface of silica coated nickel ferrite nanoparticles in the presence of organic templates was also confirmed. Antibacterial activity of the prepared nanostructures was investigated by the inactivation of Escherichia coli as a gram negative bacterium. A new mechanism was proposed for inactivation of E.... 

    Inclusion of Pediococcus acidilactici as probiotic candidate in diets for beluga (Huso huso) modifies biochemical parameters and improves immune functions

    , Article Fish Physiology and Biochemistry ; Volume 44, Issue 4 , 2018 , Pages 1099-1107 ; 09201742 (ISSN) Ghiasi, M ; Binaii, M ; Naghavi, A ; Khoshbavar Rostami, H ; Nori, H ; Amerizadeh, A ; Sharif University of Technology
    Springer Netherlands  2018
    Abstract
    Administration of probiotic candidates in fish has generally been shown as a useful strategy to improve growth performance, survival, digestive enzyme activity, and gut microbiota. Unfortunately, the sero-immunological responses of different fish to different probiotic candidates are poorly understood. The present study assessed the effect of Pediococcus acidilactici as a probiotic on the biochemical and immunological parameters of beluga. Fish (248.32 ± 10.21 g) were fed a control diet (without P. acidilactici(and three different doses of P. acidilactici-supplemented diets (107, 108, and 109 CFUg−1 diets) for 8 weeks. On week 8, blood and serum were sampled. Dose-dependent increase of... 

    Novel Pt-Ag3PO4/CdS/chitosan nanocomposite with enhanced photocatalytic and biological activities

    , Article Nanomaterials ; Volume 10, Issue 11 , May , 2020 , Pages 1-21 Kiani, M ; Bagherzadeh, M ; Kaveh, R ; Rabiee, N ; Fatahi, Y ; Dinarvand, R ; Jang, H. W ; Shokouhimehr, M ; Varma, R. S ; Sharif University of Technology
    MDPI AG  2020
    Abstract
    Decorating photocatalysts with noble metal nanoparticles (e.g., Pt) often increases the catalysts’ photocatalytic activity and biomedical properties. Here, a simple and inexpensive method has been developed to prepare a Pt-Ag3PO4/CdS/chitosan composite, which was characterized and used for the visible light-induced photocatalytic and antibacterial studies. This synthesized composite showed superior photocatalytic activity for methylene blue degradation as a hazardous pollutant (the maximum dye degradation was observed in 90 min of treatment) and killing of Gram positive bacterial (Staphylococcus aureus and Bacillus cereus) as well as Gram negative bacteria (Klebsiella pneumoniae, Salmonella... 

    A Practical Examination of the Antibacterial and Absorption Effect of Bioceramic Apatite-Coated TiO2 as a Modified Nanophotocatalyst

    , M.Sc. Thesis Sharif University of Technology Azimzadeh Irani, Maryam (Author) ; Gholami, Mohammad Reza (Supervisor) ; Haghighi, Saeed (Co-Advisor)
    Abstract
    Ag / AgCl /TiO2 , 2 Ap / Ag / AgCl /TiO , 2 AgI /TiO and 2 Ap / AgI /TiO were prepared by the deposition-precipitation method on 2TiO (P25) nanoparticles and their photocatalyctic activities have been investigated under visible light and dark environments. Cationic surfactant plus 2 PVPI (topical solution and dry powder) as an iodine ion source and nonionic surfactant plus KI as an iodide ion source were used to prepar 2 AgI /TiO . In less than 30 minutes, 2 AgI /TiO which has been resulted from combination of cationic surfactant and 2 PVPI showed high efficiency on Escherichia coli under visible light when small quantities of it is used . However, AgCl sample prepared with cationic... 

    Antibacterial Activity of Magnetic Fe3O4/X (X=Ag, Cu, Au) Nanocomposites Modified with Ionic Liquid

    , M.Sc. Thesis Sharif University of Technology karimiasl, Moslem (Author) ; Gholami, Mohammad Reza (Supervisor)
    Abstract
    In this thesis, Fe3O4 magnetic nanoparticles were produced using co-precipitation method. The surface of these magnetic nanoparticles is modified by ionic-liquid groups, and then coated with Cu, Au and Ag metals. These nanoparticles were unstable before their surface modification, so that they were easily agglomerated. However, after their surface is modified with ionic-liquid, they become very stable and are easily solved in polar and non-polar solvents. This solubility depends on the alkyls groups connected to the ionic-liquid. Magnetic nano composites Fe3O4/X (X=Ag, Cu, Au) modified by ionic-liquid are prepared by absorbing Cu(NO3)2, HAuClO4 and AgNO3 salts on the surface of modified... 

    Design, Synthesis and Use of Transition Metal Oxide Spinels (Cobalt and Iron) as Catalysts in Organic Reactions

    , M.Sc. Thesis Sharif University of Technology Aghili, Sara (Author) ; Matloubi Moghadam, Firouz (Supervisor)
    Abstract
    Bread scraps with transition metals oxides spinels have been utilized to synthesize¬ magnetic nanocatalyst. The heterogeneous catalyst was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). The reaction was performed for tandem Knoevenagel-Micheal reaction in the presence of synthesized nanocatalyst as a heterogeneous, environmentally benign, cost-effective catalyst with high catalytic activity using EtOH as a green solvent. The magnetic nanocatalyst was applied to synthesize tetraketones and pyranopyrazoles... 

    Modified Zeolitic Nanostructures: Synthesis, Characterization and the Investigation of Their Catalytic-Sorption-Antibacterial Applications

    , Ph.D. Dissertation Sharif University of Technology Padervand, Mohsen (Author) ; Gholami, Mohammad Reza (Supervisor) ; Gobal, Fereydoun (Co-Advisor)
    Abstract
    Modified zeolitic nanostructures were prepared by sol-gel, hydrothermal and coprecipitation methods. At first step, natural zeolite was used as a support for preparing the Ag/AgBr/TiO2 photocatalysts. Their photocatalytic properties were studied by degradation of pollutants and microorganism inactivation at the presence of different illumination source. These processes were mechanistically investigated and the results were explained. At second step, mordenite anocrystals, which synthesized by hydrothermal method, were used as an effective support to prepare the AgX/TiO2/MOR photocatalysts. Photocatalytic degradation of an azo dye performed over these nanocomposites and a mechanism suggested... 

    Synthesis of Fe3O4 Core-Shell Nanoparticles; Embedding Cu, Ag, Au Metals in the Surfaces that Were Modified by PPG and PEG Polymers and Investigation of Antibacterial Properties of These Composites

    , M.Sc. Thesis Sharif University of Technology Kiani Karanji, Ahmad (Author) ; Gholami, Mohammad Reza (Supervisor) ; Haghighi, Saeed (Co-Advisor)
    Abstract
    In this project, Fe3O4 magnetic nanoparticles were prepared by co-precipitation method. For protecting them against oxidation and also avoiding from direct contact between core and additional materials that probably makes unwanted reactions, the surface of nanoparticles were coated by SiO2 layer. Being easy to modify and having the control of interactions between nanoparticles are the advantages of coating nanoparticles with silica. The obtained Fe3O4@SiO2 core-shell nanoparticles were covered by two types of polymer (PPG and PEG). The basis of the composite was characterized by VSM, TGA, SEM, XRD, and FT-IR analytical methods.
    The antibacterial activities of Copper, Silver and Gold... 

    Study of Antibacterial Performance of Metal Oxide Nanostructures and their Effect on Bacterial Growth Kinetics

    , M.Sc. Thesis Sharif University of Technology Afkhami, Fatemeh Sadat (Author) ; Naseri, Naimeh (Supervisor) ; Zaker Moshfegh, Alireza (Co-Supervisor)
    Abstract
    Fighting contagious microbial diseases is considered a serious health issue, which has attracted much attention in worldwide. Thus, development of new materials based on nanostructures as a new generation of antibiotics to address this challenge has been of interest to researchers in recent years. Nanostructures based on metallic oxide semiconductors such as oxides with light absorption, production of electron-hole pairs in needle like structures cause tearing bacterial membrane and eventually destroy the bacterium. To this end, we designed experiments to study mechanism and physics governing the process of bacterial degradation to determine the best conditions for inhibiting bacteria... 

    Synthesis and Characterization of Transition Metal Complexes with Carboxamide Ligands and Nanostructures for Catalytic and Antibacterial Activites Application

    , Ph.D. Dissertation Sharif University of Technology Kiani, Mahsa (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Abstract
    Carboxamide ligands have been part of the growing research in the field of coordination chemistry of transition metal complexes. The solvent used in the classical method of synthesis of these compounds is pyridine, a solvent which is extremely toxic. In this project, we have developed a new method of synthesis using ionic liquids as the reaction media and have prepared Hqcq (1), Htp(2) under optimum conditions for Pd(II) and Pt(II) complexes of Hqcq and Co(II), Cu(II), Zn(II), Cd(II) and Hg(II) complexes of Htp with the formula:[Pd(qcq)(OAc)] (1a), [Pt(qcq)(Cl)] (1b), [Co(Htp)2(H2O)2].C2H5OH (2a), Co3O4 (2b), [Cu(tp)2(H2O)].CHCl3 (2c), CuO (2d), [Zn(tp)2(H2O)2] (2e), [Cd(tp)2(H2O)2].CH3OH... 

    Vertically aligned ZnO@CdS nanorod heterostructures for visible light photoinactivation of bacteria

    , Article Journal of Alloys and Compounds ; Vol. 590 , 2014 , pp. 507-513 ; ISSN: 09258388 Zirak, M ; Akhavan, O ; Moradlou, O ; Nien, Y. T ; Moshfegh, A. Z ; Sharif University of Technology
    Abstract
    Vertically aligned ZnO@CdS nanorod heterostructure films with various loadings of CdS nanoparticle shell were synthesized and applied in photoinactivation of Escherichia coli bacteria under visible light irradiation. While neither the bare ZnO nanorods (with band-gap energy (Eg) of ∼3.28 eV) under visible light irradiation nor the nanorod heterostructures in dark exhibited any significant antibacterial activity, the ZnO@CdS nanorod heterostructures (with Eg ∼2.5-2.6 eV) could successfully inactivate the bacteria under visible light irradiation. Furthermore, it was found that an optimum loading of the CdS shell (corresponding to the effective thickness less than ∼15 nm) is required to achieve...