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fourier-transform-infrared-spectroscopy
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Evaluations of structural, magnetic and various dielectric parameters of Ni-substituted Zn2W-type hexagonal ferrites for high frequency (1–6 GHz) applications
, Article Ceramics International ; Volume 45, Issue 18 , 2019 , Pages 24202-24211 ; 02728842 (ISSN) ; Shaukat, F ; Niaz Akhtar, M ; Ahmad, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The structural, electrical, magnetic and high frequency properties of Ni-substituted Zn2W-type hexagonal ferrites were investigated for microwave applications. Ferrite powders with chemical compositions Ba0 · 5Sr0.5NixZn2-xFe16O27 (where Ni-substitution was varied from 0.0 to 1.5 with a step size of 0.5) were prepared using sol-gel auto-combustion at 1300 °C. X-ray diffraction (XRD) analysis confirmed the single-phase hexagonal ferrite structure. The lengths of both the axis i.e. minor and major (a, c) obtained from hkl values of XRD peaks were decreased with Ni-substitution due to the difference in ionic radius of the substituted metal ions. DC electrical resistivity obtained by two-point...
Mechanical, rheological and oxygen barrier properties of ethylene vinyl acetate/diamond nanocomposites for packaging applications
, Article Diamond and Related Materials ; Volume 99 , 2019 ; 09259635 (ISSN) ; Ramazani S. A., A ; Haddadi, S. A ; Kheradmand, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this work, the effects of the surface-modified nanodiamond particles (NDs) on the barrier, rheological, mechanical and thermal properties of ethylene vinyl acetate (EVA) composites for the packaging applications were investigated. Fourier transform infrared spectroscopy, as well as thermal gravimetric analysis were employed to study the grafting of vinyltriethoxy silane (VTS) on the surface of NDs. Afterwards, EVA samples containing 0, 0.1, 0.5, 1, 1.5 and 2 wt% of surface-modified NDs were prepared by a two-stage process including the solution and injection processes. In order to evaluate the physicochemical, rheological, mechanical and thermal properties of the EVA/NDs samples, field...
Preparation and investigations on the thermal, structural and magnetic behavior of Co-Ce substituted Ni nanoferrites
, Article Materials Research Express ; Volume 6, Issue 11 , 2019 ; 20531591 (ISSN) ; Yasin, S ; Ramzan, N ; Iqbal, T ; Niaz Akhtar, M ; Sharif University of Technology
Institute of Physics Publishing
2019
Abstract
Co-Ce doped Ni nanocrystalline ferrites having composition Ni0.8Ce0.2CoxFe2-xO4 with x = 0.00, 0.25, 0.50, 0.75, 1.00 were fabricated by sol gel auto combustion method. Synthesized samples were investigated by thermal gravimetric and differential thermal analysis (TGA-DTA), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis (EDX) and vibrating sample magnetometer (VSM) to study the phase, vibrational modes, structure, surface analysis and magnetic properties respectively. Structural parameters (lattice parameters, cell volume, crystallite size and micro strains) were also calculated from XRD recorded data....
Application of a novel acrylamide copolymer containing highly hydrophobic comonomer as filtration control and rheology modifier additive in water-based drilling mud
, Article Journal of Petroleum Science and Engineering ; Volume 180 , 2019 , Pages 747-755 ; 09204105 (ISSN) ; Ramazani S.A, A ; Soleimanian, A ; Fellah Jahromi, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Deep wells suffer from the instability and disintegration of natural polymers and other commonly used additives under high pressure and high temperature condition. As a result, serious problems such as hydraulic loss, stuck pipe, and high torque and drag are expected to take place which leads to a dramatic increase in cost and time. This study presents the functionality of a novel synthetic based acrylamide-styrene copolymer (SBASC) as a supersede additive for water-based drilling mud. First, the SBASC was synthesized using an emulsion polymerization process and its particle morphological and polymer chain structural properties were determined by Field Emission Scanning Electron Microscopy...
The role of polyethylene glycol size in chemical spectra, cytotoxicity, and release of pegylated nanoliposomal cisplatin
, Article Assay and Drug Development Technologies ; Volume 17, Issue 5 , 2019 , Pages 231-239 ; 1540658X (ISSN) ; Jamehbozorgi, S ; Akbarzadeh, I ; Aghabozorg, H. R ; Amini, A ; Sharif University of Technology
Mary Ann Liebert Inc
2019
Abstract
This study aimed to synthesize methoxy polyethylene glycol propionaldehyde (mPEG20,000-ALD) for the preparation of PEGylated nanoliposomal cisplatin. Nanocarriers such as liposomes are developed for a wide range of drug delivery systems. PEG with high molecular weight (Mw) is used to coat the liposomes. In this study, simulated Fourier transform infrared (FTIR) spectra of mPEG-ALD were obtained using density functional theory (DFT) calculations and then compared with actual FTIR spectrum of mPEG20,000-ALD (Mw = 20 kDa). We found that the intensity of C = O stretching vibration at 1,700 cm-1 related to the carbonyl functional group of mPEG20,000-ALD was very weak. The results of DFT...
A detailed atomic level computational and electrochemical exploration of the Juglans regia green fruit shell extract as a sustainable and highly efficient green corrosion inhibitor for mild steel in 3.5 wt% NaCl solution
, Article Journal of Molecular Liquids ; Volume 284 , 2019 , Pages 682-699 ; 01677322 (ISSN) ; Alibakhshi, E ; Bahlakeh, G ; Ramezanzadeh, B ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Seawater, which has been frequently applied in cooling and injection water systems, imposes severe pitting corrosion to mild steel. Addition of green and sustainable inhibitors based on renewable sources is one of the promising methodologies for restricting metal corrosion in chloride-containing electrolytes. In this study, for the first time, from both theoretical and experimental faces, the role of Juglans regia green fruit shell (JRS) extract as a sustainable potent corrosion inhibitor for mild steel was studied. The chemical structure of the JRS extract was deliberated by Fourier transform infrared spectroscopy (FT-IR). By electrochemical techniques including polarization, EIS and...
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...
Controlled electrophoretic deposition of electrochemically exfoliated graphene sheets on Ag nanowires network
, Article Micro and Nano Letters ; Volume 14, Issue 4 , 2019 , Pages 389-393 ; 17500443 (ISSN) ; Tajabadi, F ; Mardi, S ; Taghavinia, N ; Amiri Zarand, A ; Dabirian, A ; Sharif University of Technology
Institution of Engineering and Technology
2019
Abstract
Electrochemical exfoliation of graphite has recently attracted a big attention as a simple, fast and scalable method for the preparation of high quality graphene, but there are some drawbacks that hinder its application. Direct deposition is one of the most critical challenges that makes it difficult to deposit uniform, compact and large scale graphene thin films. This work develops a facile electrophoretic deposition route to fabricate exfoliated graphene (EG) film on Ag nanowires (NWs) networks with a controllable film thickness in nanometers scale. EG thin films are deposited with different applied potentials and times from an EG dispersion in N, N-dimethylformamide solvent. Since...
Persian Liquorice extract as a highly efficient sustainable corrosion inhibitor for mild steel in sodium chloride solution
, Article Journal of Cleaner Production ; Volume 210 , 2019 , Pages 660-672 ; 09596526 (ISSN) ; Ramezanzadeh, M ; Haddadi, S. A ; Bahlakeh, G ; Ramezanzadeh, B ; Mahdavian, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The Persian Liquorice was introduced as a sustainable corrosion inhibitor with excellent inhibition action for mild steel in sodium chloride solution. Persian Liquorice is a root of Glycyrrhiza glabra including many active compounds like Glycyrrhizin (GL), 18β- Glycyrrhetinic acid (GA), Liquritigenin (LTG), Licochalcone A (LCA), Licochalcone E (LCE), and Glabridin (GLD). The Fourier transform infrared (FT-IR) spectroscopy was utilized to track various active components exist in the Persian Liquorice extract. Electrochemical impedance spectroscopy, potentiodynamic polarization and electrochemical current noise measurements were conducted to investigate the corrosion inhibition role of various...
Electrochemical sensors based on functionalized carbon nanotubes modified with platinum nanoparticles for the detection of sulfide ions in aqueous media
, Article Journal of Chemical Sciences ; Volume 131, Issue 3 , 2019 ; 09743626 (ISSN) ; Dolati, A ; Salmani Rezaie , S ; Sharif University of Technology
Springer
2019
Abstract
Abstract : Vertically aligned carbon nanotube (CNT) arrays were synthesized by thermal chemical vapor deposition (CVD) on stainless steel substrates coated by cobalt nanoparticles as catalyst. Morphological and elemental analyses conducted by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that bamboo-like CNTs were blocked by Co nanoparticles at the tips. The fabricated nanotubes underwent functionalization by electrochemical oxidation in sulfuric acid, and the subsequent structural studies, as well as Fourier transform infrared (FTIR) spectroscopy confirmed that the tips of functionalized CNTs were opened while oxygenated functional groups were...
A novel and cost-effective method for fabrication of a durable superhydrophobic aluminum surface with self-cleaning properties
, Article Nanotechnology ; Volume 31, Issue 46 , 2020 ; Taghvaei, E ; Moosavi, A ; Sharif University of Technology
IOP Publishing Ltd
2020
Abstract
A hierarchical superhydrophobic surface is prepared via a two-step boiling water immersion process and anodization of the treated aluminum substrate in a novel hydrophobic electrolyte of aluminum nitrate and stearic acid mixture at room temperature. The immersion time in boiling water had a significant influence on the morphology and durability of the sample. A pseudoboehmite coating is created on the aluminum surface during the boiling process, as revealed by the field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectrophotometer results. The energy-dispersive x-ray spectroscopy analysis confirmed the formation of hydrophobic coating surface after...
Impact of scale, activation solvents, and aged conditions on gas adsorption properties of UiO-66
, Article Journal of Environmental Management ; Volume 274 , 2020 ; Ahmadipouya, S ; Molavi, H ; Rezakazemi, M ; Aminabhavi, T. M ; Arjmand, M ; Sharif University of Technology
Academic Press
2020
Abstract
This work reports on the potential application of UiO-66 in gas sweetening and its structural stability against water, air, dimethylformamide (DMF), and chloroform. The UiO-66 nanoparticles were solvothermally synthesized at different scales and activated via solvent exchange technique using chloroform, methanol, and ethanol. Thus prepared and aged MOFs were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), and nitrogen adsorption-desorption analysis. The chloroform-activated MOF showed the largest surface area among all activation solvents, and presented high uptakes of 8.8 and 4.3 mmol/g for CO2...
Effect of graphene oxide on morphological and structural properties of graphene reinforced novolac-derived carbon aerogels: A modified Quasi-Percolation Model
, Article Ceramics International ; Volume 46, Issue 8 , 2020 , Pages 11179-11188 ; Madaah Hosseini, H. M ; Pourjavadi, A ; Bahramian, A. R ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Graphene reinforced polymer derived carbon (carbon/graphene) aerogels were synthesized by carbonization of novolac/graphene oxide aerogels. Novolac/graphene oxide aerogels were synthesized using solvent-saturated-vapor-atmosphere technique. To this aim, 20 wt% solution of novolac resin with 0, 2, and 5 wt% graphene oxide in 2-propanol were made and were cured in an autoclave. Wet aerogels were dried in air and were carbonized at 800 °C in nitrogen atmosphere. Eliminating the time-consuming methods of drying like supercritical and freeze drying is one of the advantages of this method of synthesis of organic aerogles. Fourier transform infrared spectroscopy, field emission scanning electron...
Optimization of alginate-whey protein isolate microcapsules for survivability and release behavior of probiotic bacteria
, Article Applied Biochemistry and Biotechnology ; Volume 190, Issue 1 , 2020 , Pages 182-196 ; Alemzadeh, I ; Vaziri, A. S ; Vossoughi, A ; Sharif University of Technology
Springer
2020
Abstract
The present study aimed to improve the survivability of L. acidophilus encapsulated in alginate-whey protein isolate (AL-WPI) biocomposite under simulated gastric juice (SGJ) and simulated intestinal juice (SIJ). Microcapsules were prepared based on emulsification/internal gelation technique. Optimal compositions of AL and WPI and their ratio in the aqueous phase were evaluated based on minimizing mean diameter (MD) of the microcapsules and maximizing encapsulation efficiency (EE), survivability of cells under SGJ (Viability), and release of viable cells under SIJ (Release) using Box-Behnken experimental design. Optimal composition comprising 4.54% (w/v) AL, 10% (w/v) WPI, and 10% (v/v)...
Amine/phenyl gradient derived base layer as a comprehensive extractive phase for headspace cooled in–tube microextraction of volatile organic compounds in saliva
, Article Journal of Pharmaceutical and Biomedical Analysis ; Volume 191 , 2020 ; Bagheri, H ; Rostami, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A gradient derived base layer extractive phase was synthesized and applied for the determination of volatile organic compounds (VOCs) in saliva samples using the headspace cooled in–tube microextraction (HS–CITME) method. The base layers from three different sols of phenyltriethoxysilane (PTES), octyltrimethoxysilane (OTMS) and methyltrimethoxysilane (MTMS) as nonpolar precursors were individually dip coated on the stainless steel wires (SSW). Then, the hydrolyzed polar precursor aminopropyltriethoxysilane (APTES) reacted with the silanol groups already formed on the surface of SSWs via controlled rate infusion (CRI) method. The presence of polar and non–polar functional groups on the...
PPI-dendrimer-functionalized magnetic metal-organic framework (fe3o4@mof@ppi) with high adsorption capacity for sustainable wastewater treatment
, Article ACS Applied Materials and Interfaces ; Volume 12, Issue 22 , 2020 , Pages 25294-25303 ; Hasanzadeh, M ; Nashtaei, M. S ; Rabbani, M ; Haji, A ; Hadavi Moghadam, B ; Sharif University of Technology
American Chemical Society
2020
Abstract
Herein, a magnetic zirconium-based metal-organic framework nanocomposite was synthesized by a simple solvothermal method and used as an adsorbent for the removal of direct and acid dyes from aqueous solution. To enhance its adsorption performance, poly(propyleneimine) dendrimer was used to functionalize the as-synthesized magnetic porous nanocomposite. The dendrimer-functionalized magnetic nanocomposite was characterized by field-emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption isotherms, and vibration sample magnetometer. The obtained results revealed the successful synthesis and functionalization of the...
Combustion synthesis of g-C3N4/Fe2O3 nanocomposite for superior photoelectrochemical catalytic performance
, Article Applied Surface Science ; Volume 534 , 2020 ; Sadrnezhaad, S. K ; Hosseini H., S. M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The g-C3N4/Fe2O3 nanocomposite was produced by the solution combustion synthesis (SCS) of iron-nitrate/g-C3N4 mixtures of varying concentration ratios and using urea as a fuel. The following methods did characterization of the products: X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller investigation (BET), ultraviolet–visible light analysis (UV–vis) and photoluminescence measurement (PL). Effect of iron nitrate on stability and photocurrent density under simulated visible-light irradiation was determined. The...
Enhanced decolorization of rhodamine B solution through simultaneous photocatalysis and persulfate activation over Fe/C3N4 photocatalyst
, Article Chemical Engineering Research and Design ; Volume 153 , 2020 , Pages 709-720 ; Padervand, M ; Soltanieh, M ; Vossoughi, M ; Sharif University of Technology
Institution of Chemical Engineers
2020
Abstract
In this study, organic contaminant degradation was intensified by increasing the oxidative capacity of the reaction system through simultaneous photocatalysis and heterogeneous persulfate activation. Fe nanoparticles were served as a multifunctional modifier to enhance the photoactivity of graphitic carbon nitride (CN), by tuning optical properties as well as persulfate (PS) activation rate, by introducing a new activation pathway. The synthesized photocatalysts were characterized by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), UV-visible...
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 ; Kohestanian, M ; Keshavarzi, N ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
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...
Nanodiamond loaded with corrosion inhibitor as efficient nanocarrier to improve anticorrosion behavior of epoxy coating
, Article Journal of Industrial and Engineering Chemistry ; Volume 83 , 2020 , Pages 153-163 ; Shojaei, A ; Pirhady Tavandashti, N ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2020
Abstract
In the present study, thermally oxidized nanodiamond (OND) was first modified non-covalently with dodecylamine (DDA) as corrosion inhibitor. In this respect, reactive primary amine of DDA molecule with high isoelectric point (IEP) could interact easily with negative charge carboxylic acid groups of OND. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) proved that OND nanoparticle was successfully functionalized by DDA up to approximately 5 wt% grafting contnet. Both OND and dodecylamine modified OND (DND) were loaded in epoxy (EP)/polyamine hardener matrix at the same concentration of 1 wt% and applied on mild steel substrate. Morphology of EP-DND and...