Search for: atomic-absorption-spectroscopy
0.007 seconds

    Experimental analysis and characterization of high-purity aluminum nanoparticles (Al-Nps) by electromagnetic levitation gas condensation (ELGC)

    , Article Nanomaterials ; Volume 10, Issue 10 , 2020 , Pages 1-15 Sabouni Tabari, R ; Halali, M ; Javadi, A. A ; Khanjanpour, M. H ; Sharif University of Technology
    MDPI AG  2020
    The production of high-purity aluminum nanoparticles (Al-NPs) is challenging due to the highly reactive nature of Al metals. Electromagnetic levitation gas condensation (ELGC) is a promising method to produce high-purity metallic particles as it avoids the interaction between molten metal and refractory-lined, which guarantees the removal of impurities such as oxygen (O). In this research, high-purity Al-NPs were successfully fabricated via ELGC process and fully characterized. The effects of power input and gas flow rate on particle size and distribution were analyzed using field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and dynamic light... 

    A novel highly dispersive magnetic nanocatalyst in water : Glucose as an efficient and green ligand for the immobilization of copper(II) for the cycloaddition of alkynes to azides

    , Article RSC Advances ; Volume 6, Issue 83 , 2016 , Pages 80234-80243 ; 20462069 (ISSN) Matloubi Moghaddam, F ; Saberi, V ; Kalhor, S ; Ayati, S. E ; Sharif University of Technology
    Royal Society of Chemistry 
    A new heterogeneous and highly dispersive nanocatalyst in water was prepared by the immobilization of Cu2+ onto glucose on Fe3O4. The catalyst was fully characterized by FT-IR, TGA, CHN, SEM, EDX, and atomic absorption spectroscopy. The synthesized catalyst was used in the synthesis of different derivatives of 1,2,3-triazole via a one-pot three-component reaction of alkynes, alkyl halides, and sodium azide. To the best of our knowledge, this novel catalyst adheres to the principles of green chemistry. The nanocatalyst could be recycled and reused in several runs without significant loss of activity  

    Elemental Characterization of the Total Suspended Particulate Matter of the Industrial City of Arak with NAA and AAS and Modeling with the AERMOD Software

    , M.Sc. Thesis Sharif University of Technology Sarlak, Mansoureh (Author) ; Sohrabpour, Mostafa (Supervisor)
    Environmental conditions of various cities of Iran are deteriorating due to various contributing effects of increased traffic, deforestation, industrial pollution etc. Arak is an example in point. It is a city of about 440,000 inhabitants. It is located at the edge of the main central desert (Kavir) of Iran. It lacks any appreciable vegetation or wooded areas and it is the home of a number of major industries. These include aluminum smelting, petrochemical industry, refinery, power plant and various other heavy manufacturing facilities. It was suggested to perform an air sampling of the city for a whole year (2010-2011) to determine the concentration of various elements by instrumental... 

    Survey of Corrosion and Biocompatibility of Metallic Biomaterials in Simulated Body Fluids

    , M.Sc. Thesis Sharif University of Technology Nourimehr, Omid (Author) ; Afshar, Abdollah (Supervisor)
    In this project, the aim is finding the corrosion behavior and biocompatibility of metallic biomaterials in simulated body fluids.by this study we can have a wide knowledge about the behavior and use of metallic biomaterials.in this project we use three base metals. Ti (grade 5 and grade 2), stainless steel (316L and 316) and Mg alloy(AZ91 and AZ31). the media was six physiological environment( Cigada solution, Hank solution, SBF solution, Fusayama solution, Ringer solution and Tyrod’s solution). all of these environments are related to the body fluids except Fusayama solution that is an artificial saliva and is a mouth fluid. we used polarization tests to determine the corrosion behavior... 

    Activated layered manganese oxides with deposited nano-sized gold or silver as an efficient catalyst for epoxidation of olefins

    , Article RSC Advances ; Volume 3, Issue 46 , 2013 , Pages 24069-24074 ; ISSN: 20462069 Najafpour, M. M ; Amini, M ; Sedigh, D. J ; Rahimi, F ; Bagherzadeh, M ; Sharif University of Technology
    Activated layered manganese oxides with deposited nano-sized gold or silver were synthesized and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectrometry, atomic absorption spectroscopy and energy-dispersive X-ray mapping. Here, we report that Au or Ag nanoparticles deposited on layered Mn oxides improve the catalytic activity of the Mn oxides toward the epoxidation of olefins in the presence of H2O2 and NaHCO3  

    A highly reactive and magnetic recyclable catalyst based on silver nanoparticles supported on ferrite for n-monoalkylation of amines with alcohols

    , Article Applied Organometallic Chemistry ; Volume 31, Issue 10 , 2017 ; 02682605 (ISSN) Bayat, A ; Shakourian Fard, M ; Nouri, P ; Mahmoodi Hashemi, M ; Sharif University of Technology
    Fe3O4@SiO2-Ag catalyst was found to be highly active and selective in the N-alkylation of amines with a variety of aromatic and linear alcohols. The heterogeneous nature of the Fe3O4@SiO2-Ag catalyst allows easy recovery and regeneration by applying an external magnet for six subsequent reaction cycles. The prepared catalyst was characterized using electron microscopy techniques, X-ray diffraction, vibrating sample magnetometry and atomic absorption spectroscopy. Copyright © 2017 John Wiley & Sons, Ltd  

    Palladium(II) immobilized onto the glucose functionalized magnetic nanoparticle as a new and efficient catalyst for the one-pot synthesis of benzoxazoles

    , Article Applied Organometallic Chemistry ; Volume 32, Issue 4 , April , 2018 ; 02682605 (ISSN) Matloubi Moghaddam, F ; Saberi, V ; Kalhor, S ; Veisi, N ; Sharif University of Technology
    John Wiley and Sons Ltd  2018
    Palladium(II) have been immobilized into the nano magnetic Fe3O4 which was functionalized with glucose in order to achieve a one-pot synthesis of 2-substituted benzoxazole derivatives with high yields in the diverse range of organic solvents. The nano catalyst is highly dispersive in polar solvents and can be easily recovered and reused for 6 runs without significant loss of its activity. Finally, the catalyst was fully characterized by FT-IR, TGA, CHN, SEM, EDX and atomic absorption spectroscopy. Copyright © 2018 John Wiley & Sons, Ltd  

    Photocatalytic activity of TiO 2-capped ZnO nanoparticles

    , Article Journal of Materials Science: Materials in Electronics ; Volume 23, Issue 2 , 2012 , Pages 361-369 ; 09574522 (ISSN) Lak, A ; Simchi, A ; Nemati, Z. A ; Sharif University of Technology
    Using a combined hydrothermal and sol-gel route, TiO 2 -capped ZnO nanoparticles with an average size of 60 nm were prepared. The titania shell was amorphous with a thickness of ∼10 nm. Formation of Zn 2TiO 4 phase at higher calcination temperature was noticed. Effects of Ti/Zn molar ratio and coating time on the thickness of TiO 2 shell and the photoactivity of the particles for decolorization of Methylene Blue (MB) under UV lamp irradiation (3 mW/cm 2) were investigated. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, fourier-transform infrared spectrometry (FTIR), diffuse reflectance spectroscopy (DLS), and atomic absorption spectroscopy.... 

    Study of the effect of frequency in pulse electrodeposition on Au-Ni from cyanide-citrate electrolyte by the aim of design of experiment

    , Article Advanced Materials Research, 15 December 2011 through 18 December 2011 ; Volume 410 , December , 2012 , Pages 377-381 ; 10226680 (ISSN) ; 9783037853160 (ISBN) Moakhar, R. S ; Imanieh, I ; Ghorbani, M ; Dolati, A ; Sharif University of Technology
    The aim of this paper is to study the influence of frequency in pulse electrodeposition, on the current efficiency, Ni content and surface morphology of deposits from a novel cyanide-citrate electrolyte with 20 mM gold as KAu(CN) 2 and 7 mM NiSO 4, with the aim of design of experiment by respond surface method (RSM). Frequency was in the range of 1-200 Hz in constant average current density, temperature, and duty cycle of 7 mA/cm 2, 59 °C and 55% respectively. Composition of the deposits was determined by atomic absorption spectroscopy (AAS). Additionally, deposits were characterized by scanning electron microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDS). It was shown that from... 

    Nanoparticle supported, magnetically separable manganese porphyrin as an efficient retrievable nanocatalyst in hydrocarbon oxidation reactions

    , Article RSC Advances ; Volume 6, Issue 47 , 2016 , Pages 41551-41560 ; 20462069 (ISSN) Bagherzadeh, M ; Mortazavi Manesh, A ; Sharif University of Technology
    Royal Society of Chemistry 
    A manganese porphyrin, meso-tetrakis(pentafluorophenyl)porphyrinato manganese(iii) acetate, Mn(TPFPP)OAc, was immobilized on silica-coated magnetic Fe3O4 nanoparticles functionalized with 3-aminopropyltriethoxysilane (APTS) through the amino propyl linkage using a grafting process in toluene solvent. This enabled the covalent immobilization of Mn(iii) porphyrin via an aromatic nucleophilic substitution reaction, to afford the Fe3O4@SiO2-NH2@MnPor catalyst. The resulting nanoparticles were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), FT-IR spectroscopy, UV-Vis spectroscopy, elemental analysis (CHN), atomic absorption spectroscopy (AAS), and vibrating... 

    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... 

    Immersed single-drop microextraction-electrothermal vaporization atomic absorption spectroscopy for the trace determination of mercury in water samples

    , Article Journal of Hazardous Materials ; Volume 165, Issue 1-3 , 2009 , Pages 353-358 ; 03043894 (ISSN) Bagheri, H ; Naderi, M ; Sharif University of Technology

    Immobilization of Au nanoparticles on poly(glycidyl methacrylate)-functionalized magnetic nanoparticles for enhanced catalytic application in the reduction of nitroarenes and Suzuki reaction

    , Article Applied Organometallic Chemistry ; Volume 34, Issue 10 , 2020 Pourjavadi, A ; Kohestanian, M ; Keshavarzi, N ; Sharif University of Technology
    John Wiley and Sons Ltd  2020
    We report a novel strategy for the synthesis of magnetic nanocomposite for highly efficient catalysis. Poly(glycidyl methacrylate) (PGMA) chains were grafted to the surface of magnetic nanoparticles (MNPs) through surface-initiated reversible addition-fragmentation chain transfer polymerization. Then, the oxirane rings in the PGMA chains were opened with 2,6-diamino pyridine (DAP) molecules as ligands to prepare the solid support. Finally, this magnetic nanocomposite was used for the immobilization of gold nanoparticles. Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, gel permeation... 

    Efficient and green oxidative degradation of methylene blue using Mn-doped ZnO nanoparticles (Zn1−xMnxO)

    , Article Journal of Experimental Nanoscience ; Volume 10, Issue 16 , 2015 , Pages 1256-1268 ; 17458080 (ISSN) Khaksar, M ; Amini, M ; Boghaei, D. M ; Sharif University of Technology
    Taylor and Francis Ltd  2015
    Mn-doped ZnO nanoparticles, Zn1−xMnxO, were synthesised by a polyethylene glycol (PEG) sol–gel method and the physicochemical properties of compounds were characterised by atomic absorption spectroscopy (AAS), energy-dispersive X-ray analysis, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The catalytic degradation of an organic dye, methylene blue (MB), in the presence of Zn1−xMnxO as the catalyst and hydrogen peroxide (H2O2) as the oxidant at room temperature in water has been studied. Effects of oxidant, catalyst amount, catalyst composition, pH value of the solution and an OH-radical...