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Imprinted silica nanofiber formation via sol-gel-electrospinning for selective micro solid phase extraction
, Article New Journal of Chemistry ; Volume 42, Issue 16 , 2018 , Pages 13864-13872 ; 11440546 (ISSN) ; Bagheri, H ; Es Haghi, A ; Sharif University of Technology
Royal Society of Chemistry
2018
Abstract
Sol composition and ripening conditions are two important parameters in silica fiber production through the conventional sol-gel process. In the current study, silica nanofibers were successfully obtained via the electrospinning technique, and sol-gel formation occurred during this process. Based on previous reports, with the aim of increasing the selectivity, we used the molecular imprinted methodology to produce a selective medium via sol-gel electrospinning. In this process, sol-gel was formed during electrospinning and then, the backbone polymer was removed by heating. To obtain a thin layer of silica nanofibers, the influencing parameters such as backbone polymer types, imprinting time...
Electrospun Ag-decorated reduced GO-graft-chitosan composite nanofibers with visible light photocatalytic activity for antibacterial performance
, Article Chemosphere ; Volume 299 , 2022 ; 00456535 (ISSN) ; Mohammadi Ziarani, G ; Badiei, A ; Setayeshmehr, M ; Kiani, M ; Pourjavadi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The treatment of water contaminated by bacteria is becoming a necessity. The nanomaterials possessing both intrinsic antibacterial properties and photocatalytic activity are excellent candidates for water disinfection. The powdered form of nanomaterials can be aggregated while embedding the nanomaterials into the NFs can overcome the limitation and enhance the photocatalytic activity and transition from UV-light to visiblelight. Here, graphene oxide (GO) was synthesized, grafted to chitosan, and decorated with silver nanoparticles (Ag NPs) to produce Ag-decorated reduced GO-graft-Chitosan (AGC) NPs. The blends of polyacrylonitrile (PAN) and AGC NPs were prepared in various concentrations of...
Transition metal ions-doped polyaniline/graphene oxide nanostructure as high performance electrode for supercapacitor applications
, Article Journal of Solid State Electrochemistry ; 2017 , Pages 1-14 ; 14328488 (ISSN) ; Shahrokhian, S ; Zad, A. I ; Sharif University of Technology
Abstract
Polyaniline/graphene oxide (PANI/GO) co-doped with Zn2+ and Fe3+ was synthesized via a simple and low cost one-step chronoamperometry method on stainless steel (SS) as the substrate. The Fe3+-Zn2+-PANI/GO nanocomposite is characterized using X-ray diffraction as well as Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy. Also, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy are used to study the electrochemical performance of the as-prepared electrode materials. Significantly, the Fe3+-Zn2+-PANI/GO nanocomposite exhibits a specific...
One step electrodeposition of V2O5/polypyrrole/graphene oxide ternary nanocomposite for preparation of a high performance supercapacitor
, Article International Journal of Hydrogen Energy ; Volume 42, Issue 33 , 2017 , Pages 21073-21085 ; 03603199 (ISSN) ; Shahrokhian, S ; Iraji zad, A ; Sharif University of Technology
Abstract
A new ternary nanocomposite based on graphene oxide (GO), polypyrrole (PPy) and vanadium pentoxide (V2O5) is obtained via one-step electrochemical deposition process. Electrochemical deposition of V2O5, PPy and GO on a stainless steel (SS) substrate is conducted from an aqueous solution containing vanadyl acetate, pyrrole and GO to get V2O5/PPy/GO nanocomposite. Characterization of the electrode material is carried out by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). The electrochemical performance of the as-prepared nanocomposite is evaluated by...
Ternary nanostructures of Cr2O3/graphene oxide/conducting polymers for supercapacitor application
, Article Journal of Electroanalytical Chemistry ; Volume 823 , 2018 , Pages 505-516 ; 15726657 (ISSN) ; Shahrokhian, S ; Iraji Zad, A ; Sharif University of Technology
Abstract
In this work, nanostructured composites of Cr2O3-graphene oxide (Cr2O3/GO) with conducting polymers; polyaniline (PANI) and polypyrrole (PPy) with the shape of cauliflower were synthesized via s simple and low cost one-step chronoamperometry method. The structures and morphologies of the resulting ternary nanocomposites were characterized by using Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The electrochemical capacitive properties of the prepared nanocomposites were evaluated by using cycle voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. The...
Iron‑vanadium oxysulfide nanostructures as novel electrode materials for supercapacitor applications
, Article Journal of Electroanalytical Chemistry ; Volume 818 , 2018 , Pages 157-167 ; 15726657 (ISSN) ; Shahrokhian, S ; Iraji Zad, Azam ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Iron‑vanadium oxysulfide (Fe-VO-S) nanostructures with different Fe:VO atomic ratios are synthesized by a facile and low cost electrochemical deposition method. The synthesis of the various samples is confirmed by the physicochemical characterizations such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). For different Fe-VO-S nanostructures, the correlation between the physicochemical and the electrochemical properties is investigated. It is found that the Fe:VO atomic ratio has an important effect on the structure and size of the resulted particles....
Transition metal ions-doped polyaniline/graphene oxide nanostructure as high performance electrode for supercapacitor applications
, Article Journal of Solid State Electrochemistry ; Volume 22, Issue 4 , 2018 , Pages 983-996 ; 14328488 (ISSN) ; Shahrokhian, S ; Iraji Zad, A ; Sharif University of Technology
Springer New York LLC
2018
Abstract
Polyaniline/graphene oxide (PANI/GO) co-doped with Zn2+ and Fe3+ was synthesized via a simple and low cost one-step chronoamperometry method on stainless steel (SS) as the substrate. The Fe3+-Zn2+-PANI/GO nanocomposite is characterized using X-ray diffraction as well as Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy. Also, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy are used to study the electrochemical performance of the as-prepared electrode materials. Significantly, the Fe3+-Zn2+-PANI/GO nanocomposite exhibits a specific...
Synthesis of folate-modified, polyethylene glycol-functionalized gold nanoparticles for targeted drug delivery
, Article Journal of Dispersion Science and Technology ; Volume 31, Issue 4 , 2010 , Pages 492-500 ; 01932691 (ISSN) ; Vosoughi, M ; Alamzadeh, I ; Tavakoli, A ; Sharif University of Technology
Abstract
The chemical synthesis and in vitro drug delivery response of folate-modified, polyethylene glycol-functionalized gold nanoparticles were studied. Lysine-capped gold nanoparticles were first prepared. Subsequently, the widely used anticancer agent doxorubicin (DOX) was successfully attached to the surface of folate-modified, polyethylene glycol-functionalized gold nanoparticles. Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) were used to confirm the functionalization and conjugation steps in the chemical synthesis. The DOX-loading efficiency determined by UV-vis spectrometer was 80%. Drug release experiments displayed a controlled-release behavior...
Highly sensitive nonenzymetic glucose sensing platform based on MOF-derived NiCo LDH nanosheets/graphene nanoribbons composite
, Article Journal of Electroanalytical Chemistry ; Volume 808 , 2018 , Pages 114-123 ; 15726657 (ISSN) ; Shahrokhian, S ; Iraji Zad, A ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Herein, a novel sensing platform based on NiCo layered double hydroxide (LDH) nanosheets/graphene nanoribbons (GNRs) modified glassy carbon electrode is presented for sensitive non-enzymetic determination of glucose. In the first step, nanoflower-like NiCo LDH nanosheets were grown on the surface of ZIF-67 dodecahedron nanocrystals which used as sacrificial template and were further characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD) and FTIR. In the next step, in order to fabricate a mechanically stable modified electrode, the as-prepared nanosheets were mixed with...
Nano-magnetic poly (vinyl alcohol) hydrogels
, Article Advanced Materials Research ; Volume 829 , 2014 , Pages 539-543 ; ISSN: 10226680 ; ISBN: 9783037859070 ; Frounchi, M ; Dadbin, S ; Sharif University of Technology
Abstract
Surface modified magnetic nanoparticles (M-NPs) were synthetized and stabilized in poly (vinylalcohol) solution. The solutions with various magnetic nanoparticles contents were gammairradiated and magnetic poly (vinyl-alcohol) (M-PVA) hydrogels were synthesized. The magnetic hydrogels and also the un-irradiated magnetic poly (vinyl alcohol) nanocomposite films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR) and mechanical measurement. The M-NPs were uniformly dispersed in the polymer matrix due to a strong interaction between the surface-modified M-NPs and polymer matrix....
Effect of gamma ray on magnetic bio-nanocomposite
, Article Materials Chemistry and Physics ; Volume 170 , 2016 , Pages 71-76 ; 02540584 (ISSN) ; Frounchi, M ; Dadbin, S ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
Magnetic polyvinyl alcohol (M-PVA) films were prepared via solution casting filled with surface modified superparamagnetic nanoparticles (M-NPs). The M-NPs were coated with citric acid during synthesis. The chemical interaction between the citric acid and M-NPs was confirmed by Fourier transform infrared spectroscopy (FTIR). The average hydrodynamic diameter of M-NPs was 19.7 nm measured by dynamic light scattering DLS and appeared almost spherical in scanning electron microscopy (SEM). The M-NPs were uniformly dispersed in polyvinyl alcohol (PVA) matrix and showed high optical transparency with good mechanical properties. M-PVA hydrogels were synthesized using gamma irradiation. The...
Content evaluation of different waste PCBs to enhance basic metals recycling
, Article Resources, Conservation and Recycling ; Volume 139 , 2018 , Pages 298-306 ; 09213449 (ISSN) ; Yaghmaei, S ; Mousavi, S. M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
This research aims to expand the body of information that researchers require before starting electronic waste (E-waste) recovery experiments. With this purpose, the basic metal contents, alkalinity, polymer components, iron magnetic separation, metal recovery priority and economic values of different types of waste printed circuit boards (PCBs) were investigated. The selected wastes were computer PCBs (CPCBs), CPCBs with wires, mobile phone PCBs (MPPCBs), television PCBs (TVPCBs), fax machine PCBs (FPCBs), copy machine PCBs (COPCBs) and central processing units (CPUs). These E-wastes were prepared in the three fraction sizes of F1<1 mm, 1 < F2<3 mm, and 3 < F3<8 mm to evaluate the metal...
Study of plastics elimination in bioleaching of electronic waste using Acidithiobacillus ferrooxidans
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 11 , 2019 , Pages 7113-7126 ; 17351472 (ISSN) ; Yaghmaei, S ; Mousavi, S. M ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
Polystyrene, acrylonitrile butadiene styrene, and polypropylene are the main polymers in E-waste, existing about 31%, 16%, and 13%, respectively. In this research, the effects of the elimination of low-density materials (such as polymers and plastics) were studied using the shaking table method. Bioleaching of Cu and Ni against the original sample (Sample #1) and pre-treated sample without low-density materials (Sample #2) was compared. The amount of bioleached metals and growth characteristics (including pH, Eh, bacterial count) was investigated within 25 days. The analysis of Sample #1 showed that at pulp density of 15 g/l, 94% and 79% of Cu and Ni were recovered maximally, respectively,...
Rapid formation of hydroxyapatite nanostrips via microwave irradiation
, Article Journal of Alloys and Compounds ; Volume 469, Issue 1-2 , 2009 , Pages 391-394 ; 09258388 (ISSN) ; Mohajerani, M ; Mazloumi, M ; Khalifehzadeh, R ; Lak, A ; Sadrnezhaad, S. K ; Sharif University of Technology
2009
Abstract
Hydroxyapatite (HAp) nanostrips were rapidly obtained during a mild microwave heating method. Applying microwave irradiation to Ca(NO3)2·4H2O/CTAB/Na2HPO4 precursor solution, the HAp precipitation process was occurred directly and without common crystallographic transformations including dissolution and slow recrystallization. The cationic surfactant CTAB was used as a soft template to modify nucleation and growth process. TEM investigations showed that the fabricated nanostrips had a width and length of about 10 and 55 nm, respectively. The X-ray diffraction pattern revealed that the fabricated well-crystallized and high purity hydroxyapatite nanostrips had a pattern similar to the bone...
Synthesis of a custom-made suspension of preformed particle gel with improved strength properties and its application in the enhancement of oil recovery in a micromodel scale
, Article Journal of Petroleum Science and Engineering ; Volume 207 , 2021 ; 09204105 (ISSN) ; Baghban Salehi, M ; Taghikhani, V ; Pahlevani, H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The objective of this work is to develop a new Preformed Particle Gel (PPG) suspension to enhance oil production and monitor water production in a porous medium on micromodel scale. To achieve the above goal, the following synthetic method was used. At the outset, the PPG samples were synthesized with polyethylene amine (PEI) as a crosslinker, 2,2′-Azobis (2-methylpropionamidine) dihydrochloride (AAPH) as initiator and acrylamide (AM) and 2-Acrylamido-2-methylpropanesulfonic acid (AMPS) monomers to improve the strength properties of PPGs by the radical polymerization method. Also, to characterize the micro and macro structural the samples, the scanning electron microscopy (SEM),...
Fabrication, modeling and optimization of lyophilized advanced platelet rich fibrin in combination with collagen-chitosan as a guided bone regeneration membrane
, Article International Journal of Biological Macromolecules ; Volume 125 , 2019 , Pages 383-391 ; 01418130 (ISSN) ; Mashayekhan, S ; Saadatmand, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, lyophilized advanced platelet rich fibrin (A-PRF) was used in combination with collagen-chitosan membrane for the first time to combine advantages of both collagen and A-PRF membranes. Response surface methodology (RSM) was used to design the experimental condition and to correlate the effects of parameters, including chitosan/collagen (chit/col) weight ratio and A-PRF concentration on Young's modulus, mesenchymal stem cell (MSCs) viability and degradation rate of the membranes. Results showed that Young's modulus of the membranes was intensified by increasing chit/col weight ratio and decreasing A-PRF concentration from 3 to 8 MPa. Cell viability of MSCs was improved by both...
Plasmonic effects of infiltrated silver nanoparticles inside TiO2 film: Enhanced photovoltaic performance in DSSCs
, Article Journal of the American Ceramic Society ; Volume 99, Issue 1 , 2016 , Pages 167-173 ; 00027820 (ISSN) ; Mohammadi, M. R ; Sharif University of Technology
Blackwell Publishing Inc
Abstract
The plasmonic effects of infiltrated silver (Ag) nanoparticles, with different contents, inside a nanostructured TiO2 film on the photovoltaic performance of dye-sensitized solar cells (DSSCs) are explored. The synthesized Ag nanoparticles are immobilized onto deposited TiO2 nanoparticles by a new strategy using 3-mercaptopropionic acid (MPA), a bifunctional linker molecule. Transmission electron microscope (TEM) images show that monodispersed Ag and polydispersed TiO2 nanoparticles have an average diameter of 12 ± 3 nm and 5 ± 1 nm, respectively. Moreover, Fourier transform infrared spectroscopy (FTIR) analysis reveals that Ag nanoparticles were successfully functionalized and capped with...
A novel formulation of simvastatin nanoemulsion gel for infected wound therapy: In vitro and in vivo assessment
, Article Journal of Drug Delivery Science and Technology ; Volume 72 , 2022 ; 17732247 (ISSN) ; Ghaffari, A ; Keramati, M ; Ahmadi, S ; Dizaji, S ; Moayer, F ; Akbarzadeh, I ; Abazari, M ; razzaghi abyaneh, M ; Bakhshandeh, H ; Sharif University of Technology
Editions de Sante
2022
Abstract
Simvastatin, a well-known antihyperlipidemic drug, has antibacterial activity against a broad range of bacteria, especially Staphylococcus aureus. In present study, a nanoemulsion gel-based formulation containing Simvastatin was developed for infected wound therapy. Therefore, different formulations of Simvastatin nanoemulsion were prepared. Based on droplet size, polydispersity index and zeta potential, the best nanoemulsion formulation containing Simvastatin was selected for development of nanoemulsion gel formulation of drug using carbomer 934 as gelling agent. Thermodynamic stability of Simvastatin nanoemulsion was assessed at different conditions. The in vitro antibacterial activity...
Preparation of ultrahigh-molecular-weight polyethylene/carbon nanotube nanocomposites with a Ziegler-Natta catalytic system and investigation of their thermal and mechanical properties
, Article Journal of Applied Polymer Science ; Volume 125, Issue SUPPL. 1 , 2012 , Pages E453-E461 ; 00218995 (ISSN) ; Ramazani, S. A. A ; Izadi, H ; Sharif University of Technology
Wiley
2012
Abstract
In this research, ultrahigh-molecular-weight polyethylene (UHMWPE)/multiwalled carbon nanotube (MWCNT) nanocomposites with different nanotube concentrations (0.5, 1.5, 2.5, and 3.5 wt %) were prepared via in situ polymerization with a novel, bisupported Ziegler-Natta catalytic system. Magnesium ethoxide [Mg(OEt) 2] and surface-functionalized MWCNTs were used as the support of the catalyst. Titanium tetrachloride (TiCl 4) accompanied by triethylaluminum constituted the Ziegler-Natta catalytic system. Preparation of the catalyst and the polymerization were carried out in the slurry phase under an argon atmosphere. Support of the catalyst on the MWCNTs was investigated with Fourier transform...
A novel superhydrophilic/superoleophobic nanocomposite PDMS-NH2/PFONa-SiO2 coated-mesh for the highly efficient and durable separation of oil and water
, Article Surface and Coatings Technology ; Volume 394 , 2020 ; Siavash Moakhar, R ; Dolati, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A surface to separate oil–water mixtures is a global concern and highly needed particularly in oil industries. The present study was conducted to create a novel superhydrophilic/superoleophobic nanocomposite coating on the stainless-steel mesh for the aim of oil/water separation. Different hydrophilic resins along with PFOA as oleophobic agent with 15 flours in its chemical structure and various oxide nanoparticles containing SiO2 and TiO2 at different concentrations were studied to achieve superhydrophilic/superoleophobic surface. The fabricated nanocomposites were fully characterized via field-emission scanning microscopy (FESEM), atomic force microscopy (AFM) and Fourier-transform...