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A sensitive voltammetric morphine nanosensor based on BaFe12O19 nanoparticle-modified screen-printed electrodes
, Article Journal of the Iranian Chemical Society ; Volume 17, Issue 3 , 2020 , Pages 717-724 ; Beitollahi, H ; Yousefi, M ; Bagherzadeh, M ; Hekmati, M ; Sharif University of Technology
Springer
2020
Abstract
Morphine is a strong opioid used for the treatment of moderate to severe pain. Its use is, however, associated with adverse effects including sedation, nausea, constipation, respiratory depression, and development of tolerance as well as dependence. Thus, in this work electrochemical oxidation of morphine has been done on BaFe12O19 nanoparticles of the modified electrode. BaFe12O19 nanoparticles of the modified graphite screen-printed electrode (GSPE) and the bare GSPE were compared, representing that the modified electrode takes advantages of higher sensitivities and selectivities with lower limit of detection. Differential pulse voltammetric procedure has been used to analyze data. Results...
Improving the performance of lithium-sulfur batteries using sulfur-(TiO2/SiO2) yolk-shell nanostructure
, Article Journal of Nanostructures ; Volume 10, Issue 1 , 2020 , Pages 76-82 ; Sepahvand, S ; Hossieni, F ; Ghasemi, S ; Sanaee, Z ; Sharif University of Technology
University of Kashan
2020
Abstract
Lithium-Sulfur (Li-S) batteries are considered as one of the promising candidates for next-generation Li batteries in near future. Although, these batteries are suffering from certain drawbacks such as rapid capacity fading during the charge and discharge process due to the dissolution of polysulfides. In this paper, Sulfur/metal oxide (TiO2 and SiO2) yolk-shell structures have been successfully synthesized and utilized to overcome this problem and improve the electrochemical performance of sulfur cahtode material. Prepared materials have been characterized using Scanning Electron Microscopy(SEM), Transmission Electron Microscopy(TEM) and X-ray diffraction (XRD) techniques. The results show...
Synthesis of titania nanofibers for photocatalytic applications
, Article Synthesis and Reactivity in Inorganic, Metal-Organic and Nano-Metal Chemistry ; Volume 37, Issue 6 , 2007 , Pages 457-460 ; 15533174 (ISSN) ; Taghavinia, N ; Iraji Zad, A ; Mahdavi, M ; Chavoshi, M ; Sharif University of Technology
2007
Abstract
Titania nanofibers were prepared using a colloidal solution of Titania nanoparticles and a templating method. The preparation comprises impregnation of cellulose fibers in the solution containing Titania nanoparticles followed by thermal removal of the cellulose template. It is evidenced by scanning electron microscopy (SEM) that the residue substance consists of micron size fibers with a microstructure of nanofibers. The pore size distribution of the substance is multi-scale and fractal morphology was demonstrated with two fractal regimes with dimensions of 1.78 and 2.97 for sizes below and above 7.5nm, respectively. The surface area of the Titania fibers was measured about 250m2/g. The...
Thermochemical synthesis of CdS nanoparticles and investigation on luminescence properties
, Article Synthesis and Reactivity in Inorganic, Metal-Organic and Nano-Metal Chemistry ; Volume 37, Issue 5 , 2007 , Pages 387-390 ; 15533174 (ISSN) ; Taghavinia, N ; Rastegarzadeh, G ; Marandi, M ; Sharif University of Technology
2007
Abstract
CdS nanoparticles were synthesized by a thermochemical method by using Na2S2O3 and CdSO4 as the precursors and thioglycerol as the capping agent. We have investigated the effect of different temperatures on the size and crystalline phase of the CdS nanoparticles. The results of the optical spectroscopy and XRD analyses clarified that increasing the synthesis temperature increased the final nanoparticles size and also changed the crystalline phase of the particles from hexagonal to cubic phase. The size of the synthesized particles was less than 4nm. TEOS was also used in cooperation with thioglycerol for better surface passivation. The results of the PL analysis showed that using this...
Green synthesis of silica nanoparticles from olive residue and investigation of their anticancer potential
, Article Nanomedicine ; Volume 16, Issue 18 , 2021 , Pages 1581-1593 ; 17435889 (ISSN) ; Afjoul, H ; Shamloo, A ; Maleki, A ; Afjoul, N ; Sharif University of Technology
Future Medicine Ltd
2021
Abstract
Graphical abstract
Synthesis of tin oxide nanoparticles in order to study its properties
, Article Digest Journal of Nanomaterials and Biostructures ; Volume 16, Issue 1 , 2021 , Pages 41-49 ; 18423582 (ISSN) ; Ali, N ; Shahid, A ; Khan, S ; Alrobei, H ; Sharif University of Technology
S.C. Virtual Company of Phisics S.R.L
2021
Abstract
Pure tin oxide nanoparticles ware synthesized via Co-precipitation method. The as-synthesized nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA), X-ray diffraction (XRD) and diffuse reflectance spectroscopy (DRS). X-ray diffraction shows that tetrahedral shaped nanoparticles of crystallite size 47.35nm were prepared successfully. The crystallinity was established due the reduction in distortion ratio and dislocation density. The value of strain showed that the nanoparticles fabricated were of high stability. The direct and indirect optical band gap of as-synthesized SnO2 nanoparticles were determined from the reflectance...
Investigation on Optical and Catalytic Properties of Noble Metallic Nanoparticles in SiO2 and TiO2 Matrix
,
Ph.D. Dissertation
Sharif University of Technology
;
Moshfegh, Alireza
(Supervisor)
;
Akhavan, Omid
(Supervisor)
Abstract
Doping metal or semiconductor nanoparticles in transparent matrix have attracted much attention for practical application in recent years. From fundamental veiw point, limiting the charge carriers and exitons in nanometric scales resulted in new quantum phenomena. In this context, transparent films containing metal nanoparticles shows an absorption peak in visible region of spectrom. Thus, by choosing an appropriate metal and controlling the size and concentration of particles in corresponding matrix, we can provide coatings with a wide rang of colors. Furthermore, thin films containing metal or metal oxide nanoparticles had been considered as nanostructure materials in research and...
Factors Affecting the Efficiency of Ferrite Process for Removal of Heavy Metals (Case study of Chromium and Nickel)
, M.Sc. Thesis Sharif University of Technology ; Borgheei, Mahdi (Supervisor)
Abstract
Heavy metals, present in many industrial wastewaters, are considered as major pollutants of environment. Various methods to removal heavy metals effectively from effluents have been used in industry, yet more efficient and economical methods are required. Magnetic iron nanoparticles are known for their superior adsorption, ion exchange and electro-static forces characteristics.The aim of this study was to evaluate the efficiency of magnetic nanoparticles for removal of hexavalent chromium (VI) and Divalent nickel from wastewater and the parameters that influence the removal.The magnetite nanoparticles were prepared by co-precipitation method where produced Fe3O4 nanoparticle’s average size...
Comparative photodecolorization of red dye by anatase, rutile (TiO 2), and wurtzite (ZnO) using response surface methodology
, Article Turkish Journal of Chemistry ; Volume 36, Issue 1 , 2012 , Pages 121-135 ; 13000527 (ISSN) ; Sadrnezhaad, S. K ; Rad, M. K ; Üner, D ; Sharif University of Technology
2012
Abstract
Treatment of dye pollution containing C.I. Acid Red 14 (AR14) by a coupled photocatalytic process was studied. Titanium dioxide, in the form of anatase and rutile, and zinc oxide, were used as photocatalysts. The investigated photocatalysts were Aldrich-produced nanopowders with crystallites of a mean size of 20-30 nm and a specific surface area of about 50 m 2/g. A comparison of TiO 2(anatase), TiO 2(rutile), TiO 2(a,r), and ZnO for the decolorization of the AR14 solution was performed. Results showed that color removal followed the decreasing order of TiO 2(a,r), ZnO > TiO 2(a,r) > TiO 2(a), ZnO > TiO 2(r), ZnO >TiO 2(a,r) > TiO 2(a) > ZnO > TiO 2(r). Response surface methodology (RSM) was...
Synthesis and characterization of carbon-stabilized magnesium nanoparticles
, Article Journal of Cluster Science ; 2016 , Pages 1-9 ; 10407278 (ISSN) ; Asgari, F ; Arzi, M ; Hojaji, A ; Sadrnezhaad, S. K ; Sharif University of Technology
Springer New York LLC
2016
Abstract
Magnesium nanopowder has attracted many interests in the recent years, which has a very difficult and costly synthesis process because of its high activity. In this work, magnesium nanoparticles stabilized with amorphous carbon (Mg–C nanoparticles) were synthesized by submerged arc discharge technique in kerosene. The arc discharge was generated between two electrodes of magnesium at the arc current of 1 A and arc voltage of 50 V. Mg–C nanoparticles were characterized by various techniques. Dynamic light scattering result indicated that size of magnesium nanoparticles is about 35 nm. X-ray diffraction showed that the produced sample consisted of hexagonal magnesium and amorphous carbon and...
Synthesis and characterization of carbon-stabilized magnesium nanoparticles
, Article Journal of Cluster Science ; Volume 28, Issue 3 , 2017 , Pages 881-889 ; 10407278 (ISSN) ; Asgari, F ; Arzi, M ; Hojaji, A ; Sadrnezhaad, S. K ; Sharif University of Technology
Springer New York LLC
2017
Abstract
Magnesium nanopowder has attracted many interests in the recent years, which has a very difficult and costly synthesis process because of its high activity. In this work, magnesium nanoparticles stabilized with amorphous carbon (Mg–C nanoparticles) were synthesized by submerged arc discharge technique in kerosene. The arc discharge was generated between two electrodes of magnesium at the arc current of 1 A and arc voltage of 50 V. Mg–C nanoparticles were characterized by various techniques. Dynamic light scattering result indicated that size of magnesium nanoparticles is about 35 nm. X-ray diffraction showed that the produced sample consisted of hexagonal magnesium and amorphous carbon and...
Silver and copper nanoparticles stabilized on ionic liquids-functionalized polyhedral oligomeric silsesquioxane (POSS): Highly active and recyclable hybrid catalysts
, Article Polyhedron ; Volume 171 , 2019 , Pages 228-236 ; 02775387 (ISSN) ; Naderahmadian, A ; Eftekhari Sis, B ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Two novel heterogeneous hybrid catalysts were successfully synthesized using octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS) and ionic liquids, followed by immobilization of Cu and Ag nanoparticles. The obtained hybrid catalysts, Cu@POSS-ILs and Ag@POSS-ILs, were characterized using FT-IR, SEM, EDX, TEM, XRD and TGA. Catalytic studies demonstrated that Cu@POSS-ILs was an excellent catalyst for click reaction in aqueous medium. Furthermore, Ag@POSS-ILs was also exhibited to be an active catalyst for 4-nitrophenol (4-NP) reduction. Simple preparation and easy catalysts recovery and recyclability of Cu@POSS-ILs and Ag@POSS-ILs for at least 3 and 6 runs,...
Effect of TiO2 nanoparticles on antifouling and separation properties of PVDF/PAN blend membrane
, Article Desalination and Water Treatment ; Volume 154 , 2019 , Pages 92-100 ; 19443994 (ISSN) ; Azimi Yancheshme, A ; Tavakolmoghadam, M ; Rekabdar, F ; Safekordi, A ; Sharif University of Technology
Desalination Publications
2019
Abstract
Recently, membrane fouling has been one of the most important issues in the field of membrane technology. In this regard, TiO2 nanoparticles blended with polymeric membranes have shown to improve fouling performance. In this study, a new PVDF/PAN/TiO2 ultrafiltration blend membrane was prepared via phase inversion by dispersing TiO2 nanoparticles in the PVDF/PAN casting solutions. The effect of different concentrations of TiO2 on the characteristics of membranes (i.e., morphology, hydrophilicity, permeation performance, and antifouling properties) was investigated. Results of scanning electron microscopy analysis showed the finger-like pores and macrovoids decrease due to the presence of...
Enhanced CO sensitivity and selectivity of gold nanoparticles-doped SnO2 sensor in presence of propane and methane
, Article Sensors and Actuators, B: Chemical ; Volume 133, Issue 1 , 26 July , 2008 , Pages 352-356 ; 09254005 (ISSN) ; Khodadadi, A ; Kazemeini, M ; Mortazavi, Y ; Sharif University of Technology
2008
Abstract
We report the effect of gold nanoparticles on the sensitivity and selectivity of SnO2-based sensors for detection of CO in the presence of methane and C3H8, a model compound representing liquid petroleum gas (LPG). 1.0 wt% Au/SnO2 powder was prepared by a co-precipitation method. The powder formed was washed, dried at 150 °C, and calcined at 300 °C for 3 h. The BET surface area of SnO2 and Au/SnO2 was measured to be 210 and 110 m2/g, corresponding to 4 and 7.5 nm loose spherical particles, respectively. Responses of the Au/SnO2 and SnO2 sensors to 40-1000 ppm CO, 0.2-1.0% C3H8 and 1.0-3.0% CH4 were studied at 170-300 °C in an automated gas sensing system. In this temperature range, the...
Adsorption dynamics of surface-modified silica nanoparticles at solid-liquid interfaces
, Article Langmuir ; Volume 38, Issue 41 , 2022 , Pages 12421-12431 ; 07437463 (ISSN) ; Bastani, D ; Mohammadi, A ; Kordzadeh, A ; Sharif University of Technology
American Chemical Society
2022
Abstract
Understanding the adsorption dynamics of nanoparticles at solid-liquid interfaces is of paramount importance to engineer nanoparticles for a variety of applications. The nanoparticle surface chemistry is significant for controlling the adsorption dynamics. This study aimed to experimentally examine the adsorption of surface-modified round-shaped silica nanoparticles (with an average diameter of 12 nm), grafted with hydrophobic (propyl chains) and/or hydrophilic (polyethylene glycol chains) agents, at an aqueous solution-silica interface with spherical soda-lime glass beads (diameter of 3 mm) being used as adsorbents. While no measurable adsorption was observed for solely hydrophobic or...
Fabrication and Characterization of Antibacterial Properties of Electroceutical Wound Dressings Containing Silver and Zinc Oxide Nanoparticles
, M.Sc. Thesis Sharif University of Technology ; Pircheraghi, Gholamreza (Supervisor)
Abstract
The World Health Organization's annual statistics show that 83% of wounds are caused by bacterial infections. Diabetic ulcers affect approximately 28 million people worldwide. The use of antibacterial dressings can help control infections. Recent studies have found that electrical stimulation can accelerate wound healing. However, there is still a need for interventions that speed up epithelial tissue formation. New dressings with zinc and silver particles that have electrical activity are being developed, but research on these methods is limited. Zinc oxide nanoparticles have been used as antibacterial agents due to their unique surface properties. This research aims to use these...
Protein-directed synthesis of γ-Fe2O3 nanoparticles and their magnetic properties investigation
, Article Bulletin of the Korean Chemical Society ; Vol. 35, issue. 5 , May , 2014 , pp. 1375-1378 ; ISSN: 02532964 ; Pourjavadi, A ; Masoud, N ; Varamesh, A ; Sattari, A ; Sharif University of Technology
Abstract
In this study, maghemite (γ-Fe2O3) nanoparticles were produced using gelatin protein as an effective mediator. Size, shape, surface morphology and magnetic properties of the prepared γ-Fe2O3 nanoparticles were characterized using XRD, FT-IR, TEM, SEM and VSM data. The effects of furnace temperature and time of heating together with the amount of gelatin on the produced gelatin-Fe3O4 nanocomposite were examined to prove the fundamental effect of gelatin; both as a capping agent in the nanoscale synthesis and as the director of the spinel γ-Fe2O3 synthesis among possible Fe 2O3 crystalline structures
Molecular dynamics study of 'success evaluation' for metallic nanoparticles manipulation on gold substrate
, Article Micro and Nano Letters ; Volume 5, Issue 5 , 2010 , Pages 286-290 ; 17500443 (ISSN) ; Meghdari, A ; Jalili, N ; Amiri, F ; Sharif University of Technology
2010
Abstract
One of the key factors in the assembly of nanoparticles and controlled construction of such systems is their positioning by a manipulation system. The response of clusters that are subjected to this process is of great importance. In this study, the behaviour of metallic nanoparticles during the manipulation process on an Au substrate is investigated using molecular dynamics. Two criteria are proposed for the evaluation of success in a pushing process regarding the intactness of a nanoparticle/substrate pair. The effects of cluster material, temperature and manipulation speed on the success of the process are investigated based on the simulation results
Aggregation-based colorimetric sensor for determination of prothioconazole fungicide using colloidal silver nanoparticles (AgNPs)
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 187 , 2017 , Pages 143-148 ; 13861425 (ISSN) ; Fahimi Kashani, N ; Hormozi Nezhad, M. R ; Sharif University of Technology
Abstract
There is a growing interest in developing high-performance sensors monitoring fungicides, due to their broadly usage and their adverse effects on humans and wildlife. In the present study, a colorimetric probe has been proposed for detection of prothioconazole based on aggregation of unmodified silver nanoparticles (AgNPs). Under optimized condition, linear relationships between the concentration of prothioconazole and the absorbance ratio of A500/A395 were found over the range of 0.01 μg·mL− 1 to 0.4 μg·mL− 1 with quantification limit as low as 1.7 ng·mL− 1. Furthermore, AgNPs color change from yellow to pink-orange in presence of prothioconazole, indicates highly sensitive naked-eye...
Silver nanoparticles immobilized onto poly(4-vinylpyridine)-functionalized magnetic nanoparticles: a robust magnetically recyclable catalyst for oxidant-free alcohol dehydrogenation
, Article Applied Organometallic Chemistry ; Volume 32, Issue 2 , February , 2018 ; 02682605 (ISSN) ; Shakourian Fard, M ; Talebloo, N ; Mahmoodi Hashemi, M ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
A heterogeneous and recyclable catalyst with a high loading of silver nanoparticles was synthesized via the silver nanoparticles being supported onto the surface of magnetic nanoparticles coated with poly(4-vinylpyridine). The synthesized catalyst was used in the dehydrogenation of alcohols to corresponding carbonyl compounds. A broad diversity of alcohols was converted into their corresponding carbonyl compounds in excellent yields. The catalyst was easily recovered by applying an external magnetic field and reused for seven reaction cycles without considerable loss of activity. The catalyst was fully characterized using various techniques. Copyright © 2017 John Wiley & Sons, Ltd