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methylene-blue
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Synthesis, structural characterization and reactivity of manganese tungstate nanoparticles in the oxidative degradation of methylene blue
, Article Comptes Rendus Chimie ; Volume 18, Issue 2 , 2015 , Pages 199-203 ; 16310748 (ISSN) ; Boghaei, D. M ; Amini, M ; Sharif University of Technology
Elsevier Masson SAS
2015
Abstract
Nanoparticles of manganese tungstate (MnWO4) were prepared via an impregnation method using Mn(NO3)2 4H2O and WO3 as a source of Mn and W, respectively. The morphology of the manganese tungstate nanoparticles was studied in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). MnWO4 nanoparticles showed severe catalytic performances for the degradation of organic dye (methylene blue, MB) in the presence of tert-butyl hydrogen peroxide, TBHP, as the oxidant at room temperature in water
Photocatalytic decolorization of methylene blue using immo bilized ZnO nanoparticles prepared by solution combustion method
, Article Desalination and Water Treatment ; Volume 44, Issue 1-3 , May , 2012 , Pages 174-179 ; 19443994 (ISSN) ; Masoumbeigi, H ; Soltani, R. D. C ; Khataee, A. R ; Hashemiyan, S ; Sharif University of Technology
Taylor and Francis Inc
2012
Abstract
Photocatalytic decolorization of methylene blue (MB) in aqueous solution was investigated using ZnO nanoparticles immobilized on glass plate. The ZnO nanoparticles were prepared by solution combustion method (SCM) using zinc nitrate as oxidant and glycine as fuel. In the slurry ZnO system the separation and recycling of the photocatalyst is practically difficult. Thus, the ZnO nanoparticles were immobilized on glass supports to solve this problem. The effects of process parameters like, catalyst loading, initial dye concentration, and UV-radiation intensity have been investigated. The best results of MB removal were reported in the 1800 μW cm-2 UVC using two layers immobilized ZnO...
Porous Carrageenan-g-polyacrylamide/bentonite superabsorbent composites: swelling and dye adsorption behavior
, Article Journal of Polymer Research ; Volume 23, Issue 3 , 2016 , Pages 1-10 ; 10229760 (ISSN) ; Bassampour, Z ; Ghasemzadeh, H ; Nazari, M ; Zolghadr, L ; Hosseini, S. H ; Sharif University of Technology
Springer Netherlands
2016
Abstract
A novel superabsorbent composite based on kappa-Carrageenan (κC) was prepared by graft copolymerization of acrylamide (AAm) onto κC in the presence of bentonite powder using methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and sodium carbonate as a pore-forming agent. The swelling behavior in distilled water and in solutions with different pH values was investigated. The results indicated that with increasing carrageenan/bentonite weight ratio, the swelling capacity is increased but the gel content is decreased. The swelling rate of the hydrogels was improved by introducing sodium carbonate as pore-forming agent. The prepared superadsorbent...
Predicting the cardiac troponin I (cTnI) aptamer/methylene blue configuration using computational modeling studies: a screening search method for constructing aptasensors
, Article ChemistrySelect ; Volume 5, Issue 35 , September , 2020 , Pages 10958-10969 ; Khajehsharifi, H ; Hashemnia, S ; Shahrokhian, S ; Sharif University of Technology
Wiley-Blackwell
2020
Abstract
Acute Myocardial Infarction (AMI) is the most common cause of mortality, and cardiac troponin I (cTnI) is the gold standard for AMI diagnosis. Some aptamers have been reported to detect cTnI, but there is rarely any structural information on their binding with cTnI. There are many studies involving electrochemical aptasensors with methylene blue (MB) as a redox indicator that does not provide any significant new information. Our study, however, involves the computational modeling of the complexes of a documented 40-mer ssDNA-cTnI aptamer with its target and MB. Here, MB was used as a model system to investigate the rather complex interaction modes between small redox molecules and a...
Magnetically recoverable TiO2/SiO2/γ-Fe2O3/rGO composite with significantly enhanced UV-visible light photocatalytic activity
, Article Molecules ; Volume 25, Issue 13 , 2020 ; Mokhtarifar, M ; Bagherzadeh, M ; Lucotti, A ; Diamanti, M. V ; Pedeferri, M ; Sharif University of Technology
MDPI AG
2020
Abstract
In this paper, we report the preparation of a new composite (TiO2/SiO2/γ-Fe2O3/rGO) with a high photocatalytic efficiency. The properties of the composite were examined by different analyses, including X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), photoluminescence (PL), UV-Visible light diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy (FTIR), Raman, vibrating-sample magnetometer (VSM), and nitrogen gas physisorption (BET) studies. The photocatalytic efficiency of the proposed composite was evaluated by the degradation of methylene blue under UV and visible light, and the results were compared with titanium dioxide (TiO2), where...
Rapid biosorption of methylene blue by in situ cellulose-grafted poly 4-hydroxybenzoic acid magnetic nanohybrid: multivariate optimization and isotherm study
, Article Polymer Bulletin ; 2017 , Pages 1-14 ; 01700839 (ISSN) ; Beyki, M. H ; Kaveh, R ; Fazli, Y ; Sharif University of Technology
Abstract
In this research, an efficient biosorption system was developed for methylene blue adsorption over in situ hydrothermally synthesized magnetite 4-hydroxybenzoic acid cellulose nanohybrid. The material was characterized with EDX, VSM, FT-IR, FESEM, and TEM techniques. Results showed that the nanohybrid is a micro-cluster composed of stacked nanoscale particles. Multivariate optimization with Box–Behnken design was used to evaluate effective parameters on adsorption and their interaction. Results showed that pH, shacking time, and adsorbent dosage are effective parameters on MB adsorption. Adsorption rate is fast with equilibrium time of 5.5 min. Isotherm study revealed that the adsorption...
Rapid biosorption of methylene blue by in situ cellulose-grafted poly 4-hydroxybenzoic acid magnetic nanohybrid: multivariate optimization and isotherm study
, Article Polymer Bulletin ; Volume 75, Issue 5 , 2018 , Pages 2167-2180 ; 01700839 (ISSN) ; Beyki, M. H ; Kaveh, R ; Fazli, Y ; Sharif University of Technology
Springer Verlag
2018
Abstract
In this research, an efficient biosorption system was developed for methylene blue adsorption over in situ hydrothermally synthesized magnetite 4-hydroxybenzoic acid cellulose nanohybrid. The material was characterized with EDX, VSM, FT-IR, FESEM, and TEM techniques. Results showed that the nanohybrid is a micro-cluster composed of stacked nanoscale particles. Multivariate optimization with Box–Behnken design was used to evaluate effective parameters on adsorption and their interaction. Results showed that pH, shacking time, and adsorbent dosage are effective parameters on MB adsorption. Adsorption rate is fast with equilibrium time of 5.5 min. Isotherm study revealed that the adsorption...
Photo-degradation of organic dye by zinc oxide nanosystems with special defect structure: Effect of the morphology and annealing temperature [electronic resource]
, Article Journal of Applied Catalysis A: General ; 22 February 2014, Volume 472, Pages 198–204 ; Simchi, A. (Abdolreza) ; Ghanbari, Faegheh ; Vossoughi, M ; Sharif University of Technology
Abstract
The fabrication of strong photocatalysts applied to the degradation of organic pollutants is necessary in environmental applications. In a single-stage method, acetate precursor and poly vinyl pyrolydine are used to produce ZnO nanostructures with various morphologies in annealing temperatures ranging from 300 to 900 °C. The physical properties of the prepared nanostructures were characterized by SEM, TEM, XRD, BET, DRS, CHN analysis and PL spectroscopy. The SEM images exhibit a variety of the as-prepared hexagonal zinc oxides including wires, rods, particles and porous network of welded particles of ZnO nanoparticles. The results of the photocatalytic degradation of methylene blue as an...
Strain rate sensitivity, work hardening, and fracture behavior of an Al-Mg TiO2 nanocomposite prepared by friction stir processing [electronic resource]
, Article Journal of Metallurgical and Materials Transactions A ; August 2014, Volume 45, Issue 9, P.4073-4088 ; Simchi, A. (Abdolreza) ; Kokabi, Amirhossein ; Nosko, Martin ; Svec, Peter ; Sharif University of Technology
Abstract
Annealed and wrought AA5052 aluminum alloy was subjected to friction stir processing (FSP) without and with 3 vol pct TiO2 nanoparticles. Microstructural studies by electron backscattered diffraction and transmission electron microscopy showed the formation of an ultra-fine-grained structure with fine distribution of TiO2 nanoparticles in the metal matrix. Nanometric Al3Ti and MgO particles were also observed, revealing in-situ solid-state reactions between Al and Mg with TiO2. Tensile testing at different strain rates determined that FSP decreased the strain rate sensitivity and work hardening of annealed Al-Mg alloy without and with TiO2 nanoparticles, while opposite results were obtained...
Biocompatible magnetic N-rich activated carbon from egg white biomass and sucrose: Preparation, characterization and investigation of dye adsorption capacity from aqueous solution
, Article Surfaces and Interfaces ; Volume 15 , 2019 , Pages 157-165 ; 24680230 (ISSN) ; Zirak, M ; Zooghi Tejrag, R ; Fathi, A ; Lamei, K ; Eftekhari Sis, B ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In the present work, N-rich activated carbon was synthesized using hydrothermal carbonization of egg white biomass in the presence of sucrose, followed by chemical activation and magnetization of hydrochar in the presence of iron (II) and (III) at NaOH solution. The results showed that the sucrose has a critical role in hydrochar yield by increasing of sucrose content. This claim also proved by SEM analysis, which hydrochar morphology was changed from the layered to fused carbon spheres morphology that confirmed the increasing of nucleation site. The materials were characterized with VSM, SEM, CHN, FTIR, Raman spectroscopy and XRD techniques. Capacity of prepared magnetic activated carbon...
Novel MIL-88A/g-C 3 N 4 nanocomposites: Fabrication, characterization and application as a photocatalyst
, Article Inorganic Chemistry Communications ; Volume 102 , 2019 , Pages 221-228 ; 13877003 (ISSN) ; Gholami, M. R ; Sharif University of Technology
Elsevier B.V
2019
Abstract
The nanocomposite of g-C 3 N 4 supported by MIL-88A has been prepared via a facile hydrothermal method. The photocatalytic performance of as-prepared composite (MIL-88A/g-C 3 N 4 ) was examined by the degradation of the Methylene Blue (MB) solution under visible light. The characterization test illustrated that the MIL-88A particles were successfully dispersed on the surface of g-C 3 N 4 structure. Photoactivity results demonstrated that the MIL-88A/g-C 3 N 4 /H 2 O 2 exhibited dramatically visible light photocatalytic performance. Hydroxyl radicals ([rad]OH) are generated by dissociation of H 2 O 2 under visible irradiation can remarkably enhance the degradation rate of MB molecules....
Oxidative Degradation of Methylene Blue by Nano-Sized Particles of Metal Oxides and Synthesis, Characterization and Catalytic Activity of Novel Mo and Fe Complexes in Oxidation Reactions
, Ph.D. Dissertation Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor) ; Amini, Mojtaba (Supervisor)
Abstract
In the first part of this thesis, the application of metal oxide nanoparticles in oxidative degradation of methylene blue is discussed. Nanoparticles of manganese tungstate (MnWO4) were prepared via an impregnation method using Mn(NO3)2.4H2O and WO3 as a source of Mn and W, respectively. The morphology of the manganese tungstate nanoparticles was studied in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). MnWO4 nanoparticles showed severe catalytic performance for the degradation of organic dye (methylene blue) in the presence of tertiary-butyl hydrogen peroxide, TBHP, as the oxidant at room temperature in water. Mn doped ZnO...
The Study of the Photocatalytic Effect of ZSM-5 Zeolite
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In this study, different metal oxides were impregnated on the surface of ZSM-5 employed as photocatalysis for degradation of methylene blue dye used in the presence of ultraviolet light. The final products were characterized by powder X-ray diffraction (XRD) and fourier transform infrared (FT-IR) method. According to the proposed mechanism for the photocatalytic degradation of methylene blue based on these results, it was found that the reaction followed from the first-order mechanism. The results indicated that rate constant for pure ZSM-5 was 9.3〖 ₓ10〗^(-3) (min-1). Furthermore the impregnated ZSM-5 having 12% zinc oxide demonstrated the highest photocatalytic activity with rate constant...
Synthesis, Characterization and Photocatalytic Application of ZnO/g- C3N4 Composite Nanorods Fabricated by Combined Sol Gel-Hydrothermal Methods
, M.Sc. Thesis Sharif University of Technology ; Moshfegh, Alireza (Supervisor)
Abstract
Because of the working conditions of semiconductors at ambient temperature and pressure, degradation of organic pollutants through semiconductors photocatalysis has attracted the interest of many researchers. Because of its large exciton binding energy,high chemical and physical stability,high electron and hole mobility, and low cost; zinc oxide, an n-type semiconductor with 3.2 eV direct band gap, is widely used in applications such as photocatalysts, solar cells, and light-emitting diodes. Among various morphologies of ZnO, 1D nanostructures such as nanowires and nanorods have recieved much attention due to their high surface to volume ratio. However, the application of ZnO as a...
Synthesis of Titanium Dioxide-graphene Nanocomposite: Characterization and Photocatalyst Applications
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Mohammad Reza (Supervisor)
Abstract
TiO2 and TiO2-Graphene have been synthesized by hydrothermal method. Their physical, chemical and morphological properties have been investigated using XPS, XRD, FTIR, TEM, EDX, UV-Vis and AFM analyses. Moreover, photocatalytic efficiency of prepared materials has been examined using degradation of methylene blue. AFM image exhibited that monolayer GO with thickness of 10 nm was synthesized using modified Hummer’s method. FTIR analysis represented main characteristic peak of oxygen bond on the surface of GO, whereas for TiO2-Graphene most of oxygen functionalities on the surface were removed partially or completely. Photocatalytic degradation of MB proved this extension of light absorption....
Application of Metallic Nanoparticles in Treatment of Wastewater Containing Dyestuffs
, M.Sc. Thesis Sharif University of Technology ; Shaygan, Jalalaldin (Supervisor)
Abstract
Textile industrial wastewaters are one of the most important sources of environmental contaminants. In the recent years, use of advanced oxidation processes, by producing highly active and reactive components such as hydroxyl radicals has been proposed. The aim of this research is oxidative degradation of methylene blue dye using Cu-nanoparticles immobilized on a polymer support with H2O2 as an oxidant reagent.In general, oxidative degradation of methylene blue with hydrogen proxide in the presence of immobilized CuO nanoparticles on a polymer support as the catalyst was studied. We used polyamidoamine (PAMAM) dendrimer as the polymer support for nanoparticles. fourth generation of PAMAM was...
Preparation and Characterization of Metal-Organic Framework/Chitosan Nanocomposites to Dye Removal from Aqueous Media
, M.Sc. Thesis Sharif University of Technology ; Shojaei Segherloo, Akbar (Supervisor) ; Molavi, Hossein (Co-Supervisor)
Abstract
The amino groups present in the chemical structure of chitosan have made this material a prominent dye absorbents. But researchers have always taken steps to improve conditions and increase absorption. One of the materials that has attracted most researchers today is metal-organic frameworks. These porous materials with high surface area, optimum thermal resistance and adsorbent dye functional groups have been used as the reinfocing in the chitosan polymer field to adsorb anionic dye (methyl orange) from the aqueous media. One of metal-organic frameworks is UiO-66, which was selected as a reinforcing phase in the polymer field, due to its good stability in aqueous solutions, good thermal...
photocatalytic elimination of organic pollutant including dye and Pharmaceutical materials in batch reactor using Hierarchical ZSM-5
, M.Sc. Thesis Sharif University of Technology ; Kazemeini, Mohammad (Supervisor) ; Hosseinpour, Vahid (Co-Supervisor)
Abstract
The aim of this research is to make a hierarchical zeolite catalyst as a basis for photocatalytic removal reactions of organic pollutants including dyes and drugs. The three main parts of this thesis deal with preparing the photocatalyst, performing the characterization test and investigating the reaction in different operating conditions. To prepare zeolite, first an organic molecule was synthesized to increase the diameter of the holes and it was used along with the rest of the precursors in the hydrothermal method. To increase the efficiency of photocatalytic reactions, the silver element was deposited on the ZnO / zeolite catalyst by photodeposition method and its characteristics were...
Effects of morphology on photocatalytic performance of Zinc oxide nanostructures synthesized by rapid microwave irradiation methods
, Article Superlattices and Microstructures ; Volume 51, Issue 4 , 2012 , Pages 512-522 ; 07496036 (ISSN) ; Ghorbani, H ; Paravar, A ; Samberg, J. P ; Kajbafvala, E ; Sadrnezhaad, S. K ; Sharif University of Technology
2012
Abstract
In this study, two different chemical solution methods were used to synthesize Zinc oxide nanostructures via a simple and fast microwave assisted method. Afterwards, the photocatalytic performances of the produced ZnO powders were investigated using methylene blue (MB) photodegradation with UV lamp irradiation. The obtained ZnO nanostructures showed spherical and flower-like morphologies. The average crystallite size of the flower-like and spherical nanostructures were determined to be about 55 nm and 28 nm, respectively. X-ray diffraction (XRD), scanning electronic microscopy (SEM), Brunauer-Emmett-Teller (BET), room temperature photoluminescence (RT-PL) and UV-vis analysis were used for...
Design and Fabrication of Gold Nanocatalyst for Aerobic Oxidation
, Ph.D. Dissertation Sharif University of Technology ; Vossoughi, Manoochehr (Supervisor) ; Simchi, Abdolreza (Supervisor)
Abstract
Aerobic oxidation plays important role in industrial processes and pollutant remediation. The catalysts accelerating oxidation reaction rate are included thermal (typical) catalysts such as Pt or Au on oxide supports and photocatalysts such as TiO2 or ZnO. Although well-studied Au/TiO2 system have been under deep
investigations but Au/ZnO system have less investigated because Au/ZnO has low activity relative to Au/ZnO. Gold nanoparticles supported on ZnO nanostructures were prepared through a simple chemical-thermal method and characterized by SEM, TEM, XRD, BET and photo luminescence (PL) spectroscopy. Effect of
annealing temperature on catalytic activity of these Au/ZnO...
investigations but Au/ZnO system have less investigated because Au/ZnO has low activity relative to Au/ZnO. Gold nanoparticles supported on ZnO nanostructures were prepared through a simple chemical-thermal method and characterized by SEM, TEM, XRD, BET and photo luminescence (PL) spectroscopy. Effect of
annealing temperature on catalytic activity of these Au/ZnO...