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Polarity adjustment of a nanosilica-functionalized polyamine modified by ionic liquid for removal of Cu2+ from aqueous solutions
, Article RSC Advances ; Volume 6, Issue 17 , 2016 , Pages 14128-14133 ; 20462069 (ISSN) ; Mahmoodi Hashemi, M ; Ghavidel, N ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
The current work deals with modification of the surface of a silica-polyamine with amine-based ionic liquid (IL) and its application for removal of Cu2+ from an aqueous media. The absorbent is simply prepared from commercially available reagents. The material is characterized by FT-IR spectroscopy, thermogravimetric analysis (TGA), N2 adsorption-desorption, and transmission electronic microscopy (TEM). Effects of several parameters on absorption efficiency, as well as activity of the absorbent to other metals, are also investigated. Moreover, the reusability of the absorbent is studied at the optimized condition. © The Royal Society of Chemistry 2016
CO2 separation by supported liquid membranes synthesized with natural deep eutectic solvents
, Article Environmental Science and Pollution Research ; Volume 28, Issue 26 , 2021 , Pages 33994-34008 ; 09441344 (ISSN) ; Khan, A. L ; Gilani, M. A ; Aslam, M ; Khan, A. U ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Betaine-based natural deep eutectic solvents (NADESs), a new class of green solvents, were immobilized into a porous polyvinylidene fluoride (PVDF) support and evaluated for the separation of CO2 from CO2/N2 and CO2/CH4 mixtures. Two types of NADESs were synthesized by mixing betaine (hydrogen bond acceptor-HBA) with malic acid and tartaric acid (hydrogen bond donors-HBD) respectively. FTIR and Raman spectroscopy were studied to confirm the synthesis and purity of the NADESs. The thermal strength of the NADESs was investigated using thermogravimetric analysis. The gas permeation results of the fabricated NADES-based-supported liquid membranes (NADES-SLMs) showed that the permeability of CO2...
A novel approach for preparation of CL-20 nanoparticles by microemulsion method
, Article Journal of Molecular Liquids ; Vol. 193, issue , May , 2014 , pp. 83-86 ; Zarandi, M ; Zarei, M. A ; Soleyman, R ; Zeynali, V ; Sharif University of Technology
Abstract
2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) as one of the high energy cage nitramines has been used in various propellants and explosive formulations. The performance of energetic materials depends on its particle size and shape. Therefore, in this research, microemulsion method has been applied for the preparation of CL-20 nanoparticles via oil in water (O/W) microemulsions. The optimized formulation contains water 45%, n-butyl acetate 20.5%, sodium dodecyl sulfate (SDS, as anionic surfactant) 6.5% and 2-propanol (as co-surfactant) 26.5%. CL-20 nanoparticles that were obtained by microemulsion method are spherical with an average diameter of 25 nm, based on TEM image....
Simple and green oxidation of cyclohexene to adipic acid with an efficient and durable silica-functionalized ammonium tungstate catalyst
, Article Catalysis Communications ; Vol. 43 , 5 January , 2014 , pp. 169-172 ; Mahmoodi Hashemi, M ; Sharif University of Technology
Abstract
A novel silica-functionalized ammonium tungstate interphase catalyst has been reported as a non-nitric acid route for adipic acid production from one-pot oxidative cleavage of 30% hydrogen peroxide and catalytic amounts of p-toluenesulfonic acid (PTSA). The catalyst has been simply prepared by commercially available starting material. The structure of the catalyst has been investigated using FT-IR spectroscopy, atomic absorption, TEM, SEM and XRD analysis. The catalyst has shown good to high activity even up to 10 runs of reaction. Simple preparation of the catalyst, avoids using harmful phase transfer catalyst (PTC) and/or chlorinated additives are among the other benefits of this work
Comparison of kinetic biodegradation of potato starch based and corn starch based low density polyethylene compound in aerated sludge
, Article BioTechnology: An Indian Journal ; Volume 7, Issue 5 , 2013 , Pages 163-168 ; 09747435 (ISSN) ; Khoramnejadian, S ; Hejazi, B ; Sharif University of Technology
2013
Abstract
The biodegradability rates of two different kinds of polyethylene bonded with corn and potato starch are studied in this paper. While it is usual to use soil as the environment for biodegradation, an aerated sludge tank was used in this studywhich offers a richermicrobialmediumand increases the rate of biodegradation. The biodegradability is determined by two ways: first, comparing differences in the weight change of two samples, one placed inside distilled water and the other placed in aerated sludge tank. Second test for biodegradation is by examination of FTIR spectroscopy. Through FTIR spectroscopy, the biodegradability rate and reduction in some of the existing bonds in polymer before...
Silica-supported DABCO-tribromide: A recoverable reagent for oxidation of alcohols to the corresponding carbonyl compounds
, Article Scientia Iranica ; Volume 20, Issue 3 , 2013 , Pages 598-602 ; 10263098 (ISSN) ; Masoud, N ; Foroushani, B. K ; Saryazdi, S ; Ghonouei, N ; Daemi, E ; Sharif University of Technology
2013
Abstract
In this study, 1,4-diazabicy lo[2.2.2] octane (DABCO) tribromide was immobilized on silica support by using 3-chloro propyl trimethoxy silane to obtain a silica-supported DABCO tribromide reagent. The synthesized reagent was characterized with elemental analysis, FT-IR spectroscopy, and thermo-gravimetric analysis (TGA). This reagent has been applied in the conversion of alcohol to corresponding carbonyl compounds. Alcohol oxidation reactions yield in 52-95%, and the reagent may be recycled five times with further bromine treatment
Exploration of an easily synthesized fluorescent probe for detecting copper in aqueous samples
, Article Dalton Transactions ; Volume 46, Issue 45 , 2017 , Pages 15827-15835 ; 14779226 (ISSN) ; García Deibe, A. M ; Fondo, M ; Zarepour Jevinani, M ; Domínguez González, M. R ; Bermejo Barrera, P ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
An easily synthesized fluorescent probe for detecting copper in aqueous samples, with a short response time and at neutral pH, has been investigated. Through the chelation of Cu2+ ions or by binding to CuO nanoparticles, the fluorescence emission of the 2-(aminomethyl)aniline derivative H2L is quenched by over 50%. Spectroscopic determination of the association constants of H2L with some metal ions showed that the ligand has a higher affinity toward Cu2+ than toward other d-block metal ions. The comparative bonding ability of the aniline-based fluorescent probe in d-block metal complexes was studied in solution by a combination of UV-Vis, 1H NMR and mass spectrometry analyses. Besides these,...
A new investigation of wax precipitation in iranian crude oils: Experimental method based on FTIR spectroscopy and theoretical predictions using PC-SAFT model
, Article Journal of Molecular Liquids ; Volume 249 , 2018 , Pages 970-979 ; 01677322 (ISSN) ; Ghotbi, C ; Jafari Behbahani, T ; Sharifi, Kh ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Temperature dependency of infrared band intensity for methylene rocking vibration could be used as indication for creation of solid crystals while decreasing temperature. In this work, different experiments were conducted to measure wax appearance temperature, WAT, such as cross polarized microscopy, rheometry and FTIR spectroscopy. Three Iranian crude oils were characterized based on the SARA test and PC-SAFT model was developed to predict WAT. The obtained results by FTIR spectroscopy and PC-SAFT model were in quite agreement. FTIR spectroscopy determined higher WAT values which may be due to its higher sensitivity to smaller wax crystals. Also, the effect of a polymeric crystal modifier...
Efficient removal of some anionic dyes from aqueous solution using a polymer-coated magnetic nano-adsorbent
, Article Journal of Water Supply: Research and Technology - AQUA ; Volume 66, Issue 4 , 2017 , Pages 239-248 ; 00037214 (ISSN) ; Haratipour, P ; Ahmadi, M ; Zare Dorabei, R ; Mahmoodi, A ; Sharif University of Technology
Abstract
For the efficient removal of some anionic dyes, a novel adsorbent was developed. The adsorbent was prepared by coating a synthetic polymer on magnetite nanosphere surface as a magnetic carrier. The synthesized nano-adsorbent was fully characterized using Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer, X-ray diffractometer, scanning electron microscope, and transmission electronic microscopy measurements. The synthesized nano-adsorbent showed high adsorption capacity towards removal of some anionic dyes (221.4, 201.6, and 135.3 mg g-1 for reactive red 195, reactive yellow 145, and reactive blue 19 dye, respectively) from aqueous samples. The dye adsorption was...
Investigation of synergistic effect of nano sized Ag/TiO2 particles on antibacterial, physical and mechanical properties of UV-curable clear coatings by experimental design
, Article Progress in Organic Coatings ; Vol. 77, issue. 2 , February , 2014 , pp. 502-511 ; ISSN: 03009440 ; Bastani, S ; Hashemi, M. M ; Sharif University of Technology
Abstract
The synergistic effect of nano titanium dioxide (10 and 30 nm) and nano silver (10 nm) as antibacterial agents were investigated on UV curable clear coating. Antibacterial and physical-mechanical properties of coating were optimized using experimental design in response surface method. Twenty different samples of nano Ag and nano TiO2 were prepared in this method. Antibacterial properties on Gram-negative bacteria (Escherichia coli) were investigated. The results revealed that using equal amounts of two sizes of nano TiO2 promote the antibacterial activity of nano Ag. So, the coating shows strong activity against E. coli. Physical-mechanical properties such as surface hardness, abrasion...
Controlled microwave-assisted synthesis of ZnFe 2 O 4 nanoparticles and their catalytic activity for O-acylation of alcohol and phenol in acetic anhydride
, Article Scientia Iranica ; Volume 19, Issue 6 , December , 2012 , Pages 1597-1600 ; 10263098 (ISSN) ; Doulabi, M ; Saeidian, H ; Sharif University of Technology
2012
Abstract
ZnFe2O4 nanoparticles have been successfully prepared through a controlled microwave-assisted co-precipitation. X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM) were used for the structural, morphological and magnetic investigation of the product. SEM micrographs of ZnFe2O4 nanopowder also reveal that nanoparticles have spherical shape. Average particle size was obtained as 12 nm from XRD. Catalytic activity of ZnFe2O4 nanopowder for O-acylation of alcohol and phenol has been investigated. A trace amount of ZnFe2O4 has been effectively used as a nanocatalyst for the acylation of alcohol and...
Synthesis of wide band gap nanocrystalline NiO powder via a sonochemical method
, Article Ultrasonics Sonochemistry ; Volume 19, Issue 4 , 2012 , Pages 841-845 ; 13504177 (ISSN) ; Hosseini, S. A ; Rezaee, M ; Sadrnezhaad, S. K ; Mohammadyani, D ; Sharif University of Technology
2012
Abstract
A sonochemistry-based synthesis method was used to produce nanocrystalline nickel oxide powder with ∼20 nm average crystallite diameter from Ni(OH)2 precursor. Ultrasound waves were applied to the primary solution to intensify the Ni(OH)2 precipitation. Dried precipitates were calcined at 320 °C to form nanocrystalline NiO particles. The morphology of the produced powder was characterized by transmission electron microscopy. Using sonochemical waves resulted in lowering of the size of the nickel oxide crystallites. FT-IR spectroscopy and X-ray diffraction revealed high purity well-crystallized structure of the synthesized powder. Photoluminescence spectroscopy confirmed production of a wide...
Mechanical and surface properties of e-beam irradiated polytetrafluoroethylene-silicone rubber composites
, Article Polymers and Polymer Composites ; Volume 18, Issue 6 , 2010 , Pages 329-336 ; 09673911 (ISSN) ; Kashcooli, Y ; Frounchi, M ; Sharif University of Technology
2010
Abstract
Compounding electron beam irradiated polytetrafluoroethylene (PTFE or Teflon) powder with silicone rubber produced silicone rubber/PTFE composites with desired physical properties. PTFE powder was exposed to electron beam irradiation at various doses and characterized by FTIR, DSC and contact angle measurements. Irradiation of PTFE with high energy electron beam induced chain scission reactions. Irradiated PTFE showed higher degree of crystallization and lower melting point with increasing absorbed dose. Number average molecular weight of irradiated PTFE was reduced significantly at higher absorbed doses. Formation of polar groups on the surface of irradiated PTFE powder was detected by FTIR...
γ-irradiation synthesis of a smart hydrogel: Optimization using taguchi method and investigation of its swelling behavior
, Article Scientia Iranica ; Volume 17, Issue 1 C , June , 2010 , Pages 15-23 ; 10263098 (ISSN) ; Soleyman, R ; Bardajee, Gh. R ; Seidi, F ; Sharif University of Technology
2010
Abstract
In the current work, synthesis of an environmental-sensitive superabsorbent hydrogel using γ-rays is described. Grafted polyacrylonitrile onto a homogeneous solution of starch and kappa-Carrageenan hybrid backbones created a smart material with reversible behavior. The reaction parameters (i.e. acrylonitrile, starch and kappa-Carrageenan concentration, as well as γ-irradiation time) affecting the. water absorbency of the. hydrogel were optimized using the. Taguchi method, in order to achieve a hydrogel with high swelling capacity. FTIR spectroscopy was used for confirming the. structure of the final product and the morphology of the synthesized hydrogel was examined by a scanning electron...
A flow injection μ-solid phase extraction system based on electrospun polyaniline nanocomposite
, Article Journal of Chromatography A ; Volume 1433 , February , 2016 , Pages 34–40 ; 00219673 (ISSN) ; Khanipour, P ; Roostaie, A ; Sharif University of Technology
Abstract
In this study, a fast and sensitive flow injection μ-solid phase extraction (FI-μ-SPE) technique based on an electrospun polyaniline (PANI) nanocomposite in conjunction with gas chromatography-mass spectrometry (GC-MS) was developed. The PANI-based nanocomposite was synthesized by electrospinning of a solution containing polyvinyl alcohol (PVA)/PANI. The majority of PVA template was subsequently removed from the whole PVA/PANI nanofibers blend by exposing the electrospun nanocomposite to hot water. The homogeneity, porosity and characterization of the electrospun nanofibers were investigated by the scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Due to...
Decorative reduced graphene oxide/C3N4/Ag2O/conductive polymer as a high performance material for electrochemical capacitors
, Article Applied Surface Science ; Volume 447 , 2018 , Pages 374-380 ; 01694332 (ISSN) ; Salari, H ; Daliri, A ; Omidi, M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Here in, reduced graphene oxide/g-C3N4/Ag2O nano structure (RGO/CAO) was decorated through a facile and simple chemical method. After that RGO/CAO nano structure combined with poly aniline electrochemically to form a composite electrode. Several physicochemical techniques were applied to characterize the composite electrode such as X-ray Diffraction (XRD), Fourier Transform Infra-Red spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Furthermore, several electrochemical techniques were used to study the performance of composite electrode as an electrochemical capacitor. Results show that RGO/CAO nano...
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....
Synthesis and application of mesoporous carbon nanospheres containing walnut extract for fabrication of active protective epoxy coatings
, Article Progress in Organic Coatings ; Volume 133 , 2019 , Pages 206-219 ; 03009440 (ISSN) ; Behroozi Kohlan, T ; Momeni, S ; Ramazani S. A., A ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this article, the synthesis procedure of mesoporous carbon nanospheres (MCNSs) using silica hard-templates, doping of the nanospheres with walnut extract, and their impact on active protective properties of an epoxy coating are presented. Field emission scanning electron microscope (FE-SEM) results showed that the synthesis of these nanocontainers was successfully done in spherical form. Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR) results showed that walnut extract as a green inhibitor was doped into the pores of nanocapsules. Corrosion resistance of the mild steel samples in the 3.5 wt.% NaCl solution in the presence and absence of walnut extract...
Ni(II) 1D-coordination polymer/C 60 -modified glassy carbon electrode as a highly sensitive non-enzymatic glucose electrochemical sensor
, Article Applied Surface Science ; Volume 478 , 2019 , Pages 361-372 ; 01694332 (ISSN) ; Mohammadi, R ; Ghanbari, B ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V
2019
Abstract
A new non-enzymatic sensor for glucose is prepared by using of Ni(II)-one dimensional coordination polymer (Ni(II)-Cp) and C 60 . The Ni(II)-Cp prepared by slow diffusion and evaporation of two solution layers of NiCl 2 and diaza-macrocycle bearing two pyridine side arms (as the reported tecton) in DMF. The Ni(II)-Cp was characterized by powder x-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) as well as Fourier transform infrared spectroscopy (FT-IR). C 60 as modified was added to Ni(II)-Cp for improving the electrical and chemical stability of the composite. The newly assembled Ni(II)-Cp/C 60 also coated on glassy carbon electrode (GC) to...
Polyphosphate-reduced graphene oxide on Ni foam as a binder free electrode for fabrication of high performance supercapacitor
, Article Electrochimica Acta ; Volume 296 , 2019 , Pages 130-141 ; 00134686 (ISSN) ; Asen, P ; Shahrokhian, S ; Ahadian, M. M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Polyphosphate reduced graphene oxide on Ni foam (PPO-RGO/NF) is synthesized by varying weight ratios of Na5P3O10 (PO): graphene oxide (GO) with a simple, scalable and low cost method through freeze-drying of the PO-GO/NF followed by thermal treatment of the prepared electrodes. The resulting samples are characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), Brunauer-Emmett-Teller (BET), and raman spectroscopy methods. The results show that the weight ratio of PO:GO, considerably affect the...