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A core–shell titanium dioxide polyaniline nanocomposite for the needle-trap extraction of volatile organic compounds in urine samples
, Article Journal of Separation Science ; Volume 40, Issue 9 , 2017 , Pages 1985-1992 ; 16159306 (ISSN) ; Bagheri, H ; Sharif University of Technology
Wiley-VCH Verlag
2017
Abstract
We synthesized a titanium dioxide–polyaniline core–shell nanocomposite and implemented it as an efficient sorbent for the needle-trap extraction of some volatile organic compounds from urine samples. Polyaniline was synthesized, in the form of the emeraldine base, dissolved in dimethyl acetamide followed by diluting with water at pH 2.8, using the interfacial polymerization method. The TiO2 nanoparticles were encapsulated inside the conducting polymer shell, by adapting the in situ dispersing approach. The surface characteristics of the nanocomposite were investigated by Fourier transform infrared spectrometry, scanning electron microscopy, and transmission electron microscopy. After...
Effect of Fe-Containing supports prepared by a novel sol–gel method in the co methanation reaction: co elimination and synthetic natural gas production
, Article Energy Technology ; Volume 7, Issue 10 , 2019 ; 21944288 (ISSN) ; Rezaei, M ; Nematollahi, B ; Baghalha, M ; Sharif University of Technology
Wiley-VCH Verlag
2019
Abstract
Herein, the CO methanation reaction is studied over Ni/Fe–Al mixed oxides with various Fe and Al contents. The mesoporous nanocrystalline supports are prepared by a novel sol–gel process using propylene oxide as a gelation agent. The deposition–precipitation method is used for the deposition of nickel on the catalyst support. The samples are characterized by Brunauer–Emmett–Teller (BET), X-ray diffractometry (XRD), temperature programmed reduction (TPR), temperature programmed oxidation (TPO), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results indicate that increasing the iron content and reducing the Al percentage in the catalyst support reduces the...
Graphene oxide-l-arginine nanogel: A pH-sensitive fluorouracil nanocarrier
, Article Biotechnology and Applied Biochemistry ; Volume 66, Issue 5 , 2019 , Pages 772-780 ; 08854513 (ISSN) ; Ghaemi, A ; Masoudi, G ; Chogan, F ; Rashedi, H ; Yazdian, F ; Omidi, M ; Javadi, S ; Haghiralsadat, B. F ; Teimouri, M ; Faal Hamedani, N ; Sharif University of Technology
Wiley-Blackwell Publishing Ltd
2019
Abstract
Nowadays, putting forward an accurate cancer therapy method with minimal side effects is an important topic of research. Nanostructures, for their ability in controlled and targeted drug release on specific cells, are critical materials in this field. In this study, a pH-sensitive graphene oxide-l-arginine nanogel was synthesized to carry and release 5-fluorouracil. Optimized conditions using statistical analysis, based on the maximum relative viscosity of nanogel, were evaluated: 5.489 for the concentration of l-arginine and 2.404 for pH. The prepared nanogels were characterized using scanning electron microscope and transmission electron microscope images and Fourier-transform infrared...
Novel microfluidic graphene oxide–protein amperometric biosensor for detecting sulfur compounds
, Article Biotechnology and Applied Biochemistry ; Volume 66, Issue 3 , 2019 , Pages 353-360 ; 08854513 (ISSN) ; Abdi, K ; Javadi, S ; Shehneh, M. Z ; Yazdian, F ; Omidi, M ; Rashedi, H ; Haghiralsadat, B. F ; Asayeshnaeini, O ; Sharif University of Technology
Wiley-Blackwell Publishing Ltd
2019
Abstract
Sulfur compounds are essential for many industries and organisms; however, they cause serious respiratory problems in human beings. Therefore, determination of sulfur concentration is of paramount importance. The research approach in the field of detecting contaminants has led to smaller systems that provide faster and more effective ways for diagnosis purposes. In this study, a novel portable amperometric graphene oxide–protein biosensor platform is investigated. The main characteristic of this structure is the implementation of a microfluidic configuration. With albumin metalloprotein as the biorecognition element, graphene oxide was synthesized and characterized by transmission electron...
Evolution of quantum electronic features with the size of silicon nanoparticles embedded in a SiO2 layer obtained by low energy ion implantation
, Article 11th International Autumn Meeting on Gettering and Defect Engineering in Semiconductor Technlogy, GADEST 2005, Giens, 25 September 2005 through 30 September 2005 ; Volume 108-109 , 2005 , Pages 71-76 ; 10120394 (ISSN); 3908451132 (ISBN); 9783908451136 (ISBN) ; Shalchian, M ; BenAssayag, G ; Coffin, H ; Bonafos, C ; Dumas, C ; Atarodi, S. M ; Claverie, A ; Sharif University of Technology
Trans Tech Publications Ltd
2005
Abstract
In this paper, we have studied the evolution of quantum electronic features with the size of silicon nanoparticles embedded in an ultra-thin SiO 2 layer. These nanoparticles were synthesized by ultralow energy (1 KeV) ion implantation and annealing. Their size was modified using the effect of annealing under slightly oxidizing ambient (N2+O2). Material characterization techniques including transmission electron microscopy (TEM) Fresnel imaging and spatially resolved electron energy loss spectroscopy (EELS) have been used to evaluate the effects of oxidation on structural characteristics of nanocrystal layer. Electrical transport characteristics have been measured on few (less than two...
Evolution of quantum electronic features with the size of silicon nanoparticles embedded in a sio2 layer obtained by low energy ion implantation
, Article 11th International Autumn Meeting on Gettering and Defect Engineering in Semiconductor Technology, GADEST 2005, 25 September 2005 through 30 September 2005 ; Volume 108-109 , 2005 , Pages 71-76 ; 10120394 (ISSN); 9783908451136 (ISBN) ; Shalchian, M ; Benassayag, G ; Coffin, H ; Bonafos, C ; Dumas, C ; Atarodi, S. M ; Claverie, A ; Pichaud B ; Claverie A ; Alquier D ; Richter H ; Kittler M ; Richter H ; Kittler M ; Sharif University of Technology
Trans Tech Publications Ltd
2005
Abstract
In this paper, we have studied the evolution of quantum electronic features with the size of silicon nanoparticles embedded in an ultra-thin SiO2 layer. These nanoparticles were synthesized by ultralow energy (1 KeV) ion implantation and annealing. Their size was modified using the effect of annealing under slightly oxidizing ambient (N2+O2). Material characterization techniques including transmission electron microscopy (TEM) Fresnel imaging and spatially resolved electron energy loss spectroscopy (EELS) have been used to evaluate the effects of oxidation on structural characteristics of nanocrystal layer. Electrical transport characteristics have been measured on few (less than two...
Efficient and green oxidative degradation of methylene blue using Mn-doped ZnO nanoparticles (Zn1−x Mnx O)
,
Article
Journal of Experimental Nanoscience
;
Volume 10, Issue 16
,
2015
,
Pages 1256-1268
;
17458080 (ISSN)
; Amini, M
; Boghaei, D. M
;
Sharif University of Technology
Taylor and Francis Ltd
2015
Abstract
Mn-doped ZnO nanoparticles, Zn1−x Mnx O, 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−x Mnx O as the catalyst and hydrogen peroxide (H2 O2 ) 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...
Doxorubicin-conjugated D-glucosamine- and folate- bi-functionalised InP/ZnS quantum dots for cancer cells imaging and therapy
, Article Journal of Drug Targeting ; Volume 26, Issue 3 , 2018 , Pages 267-277 ; 1061186X (ISSN) ; Eskandani, M ; Johari Ahar, M ; Nemati, A ; Akbari, H ; Davaran, S ; Omidi, Y ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
Nanoscaled quantum dots (QDs), with unique optical properties have been used for the development of theranostics. Here, InP/ZnS QDs were synthesised and functionalised with folate (QD-FA), D-glucosamine (QD-GA) or both (QD-FA-GA). The bi-functionalised QDs were further conjugated with doxorubicin (QD-FA-GA-DOX). Optimum Indium to fatty acid (In:MA) ratio was 1:3.5. Transmission electron microscopy (TEM) micrographs revealed spherical morphology for the QDs (11 nm). Energy-dispersive spectroscopy (EDS) spectrum confirmed the chemical composition of the QDs. MTT analysis in the OVCAR-3 cells treated with bare QDs, QD-FA, QD-GA, QD-FA-GA and QD-FA-GA-DOX (0.2 mg/mL of QDs) after 24 h indicated...
Simultaneous use of physical and chemical dispersants for electrical conductivity enhancement in polyamide 6/carbon nanotube/conductive carbon black hybrid nanocomposites
, Article Polymer-Plastics Technology and Materials ; 2021 ; 25740881 (ISSN) ; Jahanaray, B ; Pircheraghi, G ; Bagheri, R ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
Polyamide 6 (PA6)/carbon nanotube (CNT)/conductive carbon black (CCB) nanocomposites with the incorporation of physical and chemical dispersants were prepared via melt blending method to examine the synergistic enhancement of electrical conductivity. Investigation of modified CNT with octadecyl triphenyl phosphonium chloride (OTPC-CNT) as physical dispersant was performed by Fourier transform infrared, nuclear magnetic resonance, Raman spectroscopy, and thermogravimetric analysis. Morphological, electrical, rheological, and mechanical properties of PA6/CNT/CCB nanocomposites were examined by field emission scanning electron microscopy, transmission electron microscopy, digital insulation...
Simultaneous use of physical and chemical dispersants for electrical conductivity enhancement in polyamide 6/carbon nanotube/conductive carbon black hybrid nanocomposites
, Article Polymer-Plastics Technology and Materials ; Volume 61, Issue 3 , 2022 , Pages 263-275 ; 25740881 (ISSN) ; Jahanaray, B ; Pircheraghi, G ; Bagheri, R ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Polyamide 6 (PA6)/carbon nanotube (CNT)/conductive carbon black (CCB) nanocomposites with the incorporation of physical and chemical dispersants were prepared via melt blending method to examine the synergistic enhancement of electrical conductivity. Investigation of modified CNT with octadecyl triphenyl phosphonium chloride (OTPC-CNT) as physical dispersant was performed by Fourier transform infrared, nuclear magnetic resonance, Raman spectroscopy, and thermogravimetric analysis. Morphological, electrical, rheological, and mechanical properties of PA6/CNT/CCB nanocomposites were examined by field emission scanning electron microscopy, transmission electron microscopy, digital insulation...
Modeling the Removal of Phenol Dyes Using a Photocatalytic Reactor with SnO2/Fe3O4 Nanoparticles by Intelligent System
, Article Journal of Dispersion Science and Technology ; Volume 36, Issue 4 , Apr , 2015 , Pages 540-548 ; 01932691 (ISSN) ; Hedayati Moghaddam, A ; Nouri, A ; Shayegan, J ; Sharif University of Technology
Taylor and Francis Inc
2015
Abstract
The objective of this study was to model the extent of improvement in the degradability of phenol dyes by SnO2/Fe3O4 nanoparticles using a photocatalytic reactor. The effect of operative parameters including catalyst concentration, initial dye concentration, stirring intensity, and UV radiation intensity on the photocatalytic batch reactor during removal of phenol red was investigated. Fractional factorial design and response surface methodology were used to design the experiment layout. The SnO2/Fe3O4 nanoparticles were synthesized using the core-shell method. The results of x-ray diffraction and transmission electron microscopy showed the successful synthesis of these nanoparticles. The...
Smart magnetic self-assembled micelle: an effective nanocarrier for thermo-triggered paclitaxel delivery
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 68, 2019 - Issue 12 , October , 2018 , Pages 741-749 ; 00914037 (ISSN) ; Mazaheri Tehrani, Z ; Dastanpour, L ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
Magnetic micelle nanoparticles with thermoresponsive behavior were designed for thermo-triggered paclitaxel delivery. For this purpose, thermoresponsive triblock copolymer poly(N-isopropyl acrylamide)-b-polycaprolactone-b-poly(N-isopropyl acrylamide) was prepared. The magnetic micelle was formed by self-assembly of triblock copolymer on the magnetite which was coated by oleic acid. The size of the magnetic micelle was between 30–40 nm reported by transmission electron microscopy. Also, dynamic light scattering indicated the hydrodynamic diameter was thermal dependent. Moreover, the drug release profile showed thermo-triggered release of paclitaxel. Thus, the smart nanocarrier has potential...
Smart magnetic self-assembled micelle: an effective nanocarrier for thermo-triggered paclitaxel delivery
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 68, Issue 12 , 2019 , Pages 741-749 ; 00914037 (ISSN) ; Mazaheri Tehrani, Z ; Dastanpour, L ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
Magnetic micelle nanoparticles with thermoresponsive behavior were designed for thermo-triggered paclitaxel delivery. For this purpose, thermoresponsive triblock copolymer poly(N-isopropyl acrylamide)-b-polycaprolactone-b-poly(N-isopropyl acrylamide) was prepared. The magnetic micelle was formed by self-assembly of triblock copolymer on the magnetite which was coated by oleic acid. The size of the magnetic micelle was between 30–40 nm reported by transmission electron microscopy. Also, dynamic light scattering indicated the hydrodynamic diameter was thermal dependent. Moreover, the drug release profile showed thermo-triggered release of paclitaxel. Thus, the smart nanocarrier has potential...
Adsorptive removal of petroleum hydrocarbons from aqueous solutions by novel zinc oxide nanoparticles grafted with polymers
, Article Petroleum Science and Technology ; Volume 34, Issue 8 , 2016 , Pages 778-784 ; 10916466 (ISSN) ; Hasani, A. H ; Ahmad Panahi, H ; Borghei, S. M ; Sharif University of Technology
Taylor and Francis Inc
Abstract
Zinc oxide nanoparticles were synthesized and modified by a three-stage method. Elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning and transmission electron microscopy, and Brunauer–Emmett–Teller method were applied to characterize the nanoparticles. These nanoparticles were evaluated for toluene adsorption from aqueous solutions as a representative of petroleum hydrocarbon removal. The optimum adsorption condition achieved at pH of 6 and contact time of 30 min. The adsorption isotherms were fitted to the Langmuir model. The measured adsorption capacity was 12.8 mg g−1. This study demonstrated that these nanoparticles could be used as an...
Graphitic carbon nitride nanosheets as a fluorescent probe for chromium speciation
, Article Microchimica Acta ; Volume 185, Issue 2 , 2018 ; 00263672 (ISSN) ; Salehnezhad, Z ; Hatamie, A ; Babapour, A ; Sharif University of Technology
Springer-Verlag Wien
2018
Abstract
A fluorometric method was developed for simultaneous determination of Cr(VI) and Cr(III) ions using graphitic carbon nitride nanosheets (g-C3N4 NS) as a nanosized fluorescent indicator probe. The g-C3N4 NS were prepared using high-temperature carbonization of melamine followed by ultrasonication-assisted liquid exfoliation. The g-C3N4 NS display fluorescence with excitation/emission peaks located at 320 and 450 nm. The chromium speciation is based on the quenching of g-C3N4 NS fluorescence. The total concentration of chromium is determined after oxidation of Cr(III) to Cr(VI). The Cr(III) content was then calculated by subtracting the concentration of Cr(VI) from that of total chromium. The...
Effect of temperature and concentration on thermal conductivity and viscosity of ferrofluid loaded with carbon nanotubes
, Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; 2015 , Pages 1-9 ; 09477411 (ISSN) ; Saghafian, M ; Salimpour, M. R ; Shafii, M. B ; Sharif University of Technology
Springer Verlag
2015
Abstract
The aim of this paper is to investigate the thermal conductivity and viscosity of a hybrid nanofluid containing tetramethylammonium hydroxide (TMAH) coated Fe3O4 nanoparticles and gum arabic (GA) coated carbon nanotubes (CNTs), experimentally. The magnetic nanoparticles and CNTs are physically attached as the result of interaction between the TMAH and GA molecules. The morphology and structure of the samples are characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM). The experiments are carried out in the magnetic nanoparticles volume concentration range of 0.1–0.9 %, CNT volume concentration range of 0.05–1.35 % and the temperature range of 25–55 °C. The...
Effect of temperature and concentration on thermal conductivity and viscosity of ferrofluid loaded with carbon nanotubes
, Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; Volume 52, Issue 10 , 2016 , Pages 2293-2301 ; 09477411 (ISSN) ; Saghafian, M ; Salimpour, M. R ; Shafii, M. B ; Sharif University of Technology
Springer Verlag
2016
Abstract
The aim of this paper is to investigate the thermal conductivity and viscosity of a hybrid nanofluid containing tetramethylammonium hydroxide (TMAH) coated Fe3O4 nanoparticles and gum arabic (GA) coated carbon nanotubes (CNTs), experimentally. The magnetic nanoparticles and CNTs are physically attached as the result of interaction between the TMAH and GA molecules. The morphology and structure of the samples are characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM). The experiments are carried out in the magnetic nanoparticles volume concentration range of 0.1–0.9 %, CNT volume concentration range of 0.05–1.35 % and the temperature range of 25–55 °C. The...
Facile one-pot synthesis of polytypic (wurtzite–chalcopyrite) CuGaS2
, Article Applied Physics A: Materials Science and Processing ; Volume 122, Issue 3 , 2016 , Pages 1-10 ; 09478396 (ISSN) ; Mirkazemi, S. M ; Tahir, M. N ; Iraji Zad, A ; Ghasemzadeh, R ; Tremel, W ; Sharif University of Technology
Springer Verlag
2016
Abstract
Abstract: In this investigation, monodisperse CuGaS2 nanoparticles intended for use as visible-light-absorbing materials were synthesized using a facile one-step heating method that involved dissolving the precursors copper chloride, gallium acetylacetonate, and thiourea in a solvent consisting of either oleylamine alone or a combination of oleylamine, oleic acid, and 1-octadecene. The shapes of the resulting nanoparticles were either elongated, polygonal, or a mixture of both, depending on whether the crystal structure of the nanoparticles was predominantly wurtzite, predominantly chalcopyrite, or a more balanced mixture of both wurtzite and chalcopyrite (i.e., the nanoparticles were...
Novel synthesis of cobalt/poly vinyl alcohol/gamma alumina nanocomposite for catalytic application
, Article Applied Physics A: Materials Science and Processing ; Volume 123, Issue 5 , 2017 ; 09478396 (ISSN) ; Ahadian, M. M ; Rashidi, A ; Karimi, A ; Akhavan, O ; Sharif University of Technology
Springer Verlag
2017
Abstract
In this manuscript, synthesis of cobalt/poly vinyl alcohol (PVA)/gamma alumina nanocomposite via a simple room temperature, as well as its catalyst performance were explored. Brunauer–Emmett–Teller analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy were conducted. The surface area of the polymeric composite was obtained to be 280 m2/g. The cobalt loading on the nanocomposite was measured using inductivity couple plasma. Transmission electron microscopy analysis showed that the size of cobalt crystalline encapsulate inside the polymer was confined to 5 nm. Magnetic property analysis, using vibrating sample magnetometer, confirmed...
Nanostructural study of NiTi–TiO2–C core–shell nanoparticles generated by spark discharge method
, Article Applied Physics A: Materials Science and Processing ; Volume 124, Issue 9 , 2018 ; 09478396 (ISSN) ; Sabzehparvar, M ; Sadrnezhaad, S. K ; Amin, M. H ; Sharif University of Technology
Springer Verlag
2018
Abstract
Abstract: Nickel–titanium (NiTi) nanoparticles are ultrafine smart materials manifesting shape memory effect at very small scales. We have produced NiTi nanoparticles surrounded by an amorphous carbon shell using an innovative spark discharge system. The resulting nanoparticles were studied using various characterization methods to systematically study their size, morphology, size distribution, composition, structure, and thermal behavior. Field-emission scanning electron microscopy and dynamic light-scattering results indicated that the average size of the produced nanoparticles was about 13 nm. High-resolution transmission electron microscopy, energy-dispersive spectroscopy (EDS), and...