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Supported copper and cobalt oxides on activated carbon for simultaneous oxidation of toluene and cyclohexane in air
, Article RSC Advances ; Volume 5, Issue 7 , Dec , 2015 , Pages 5107-5122 ; 20462069 (ISSN) ; Khorasheh, F ; Shayegan, J ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Copper and cobalt oxides supported on almond shell derived activated carbon (AC) with different loadings were synthesized by sequential and co-deposition-precipitation methods leading to Cu(shell)/Co(core)/AC, Co(shell)/Cu(core)/AC and Cu-Co(mixed)/AC catalysts that were subsequently used for catalytic oxidation of gaseous mixtures of toluene and cyclohexane in air in a tubular flow reactor. The catalysts and the support were characterized by Boehm test, Brunauer-Emmett-Teller (BET) surface area, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy...
Enhanced singlet oxygen production under nanoconfinement using silica nanocomposites towards improving the photooxygenation’s conversion
, Article Journal of Nanoparticle Research ; Volume 24, Issue 9 , 2022 ; 13880764 (ISSN) ; Kazemeini, M ; Sharif University of Technology
Springer Science and Business Media B.V
2022
Abstract
In this contribution, the effect of physical immobilization of methylene blue (MB) into silica nanocomposites was investigated on the conversion and selectivity of the photooxygenation of anthracene and dihydroartemisinic acid (DHAA). Physically immobilized photocatalysts were synthesized through a developed Stöber method and were thoroughly characterized by UV–Vis, FTIR, XRD, XPS, SEM, TEM, HR-TEM, BET-BJH, and EDX analyses. Based on the TEM and UV–Vis results, it was determined that enhancement of the MB concentration as an organocatalyst for the Stöber reaction led to an increase in the size of the nanoparticles from 54 to 183 nm and a 21 nm blue shift in their UV–Vis spectra. Moreover,...
Hydrogen failure sensitivity of A516-Gr70 and API 5L-X70 steels in sour environments
, Article Anti-Corrosion Methods and Materials ; Volume 62, Issue 5 , 2015 , Pages 294-300 ; 00035599 (ISSN) ; Dolati, A ; Beidokhti, B ; Sharif University of Technology
Emerald Group Publishing Ltd
2015
Abstract
Purpose – This paper aims to clarify the corrosion behavior of two famous structural steels in sour environment. These steels have a vast application in oil and gas industries. The study aims to find the effect of different concentrations of sour solution on the origin of crack in these steels. Design/methodology/approach – After preparation of specimens, different sour solutions were made using the synthetic brine (according to National Association of Corrosion Engineers [NACE], Technical Committee Report 1D182) and various amounts of Na2 S.9H2 O and CH3 COOH. The polarization test was done by Potansiostat apparatus model Zahner-IM6 at two temperatures, 25°C...
Densification and microstructural evolution during laser sintering of A356/SiC composite powders
, Article Journal of Materials Science ; Volume 46, Issue 5 , 2011 , Pages 1446-1454 ; 00222461 (ISSN) ; Godlinski, D ; Sharif University of Technology
Abstract
This article reports experimental results on laser sintering of A356 aluminum alloy and A356/SiC composite powders. Effects of scan rate, sintering atmosphere, hatch spacing, and SiC volume fraction (up to 20%), and particle size (7 and 17 μm) on the densification were studied. The phase formation and microstructural development were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Laser sintering under argon atmosphere exhibited higher densification compared to nitrogen. A faster sintering kinetics was observed as the scan rate decreased. Except at a low SiC content (5 vol%), the composite powders exhibited...
Enhancement in reactivity via sulfidation of FeNi@BC for efficient removal of trichloroethylene: Insight mechanism and the role of reactive oxygen species
, Article Science of the Total Environment ; Volume 794 , 2021 ; 00489697 (ISSN) ; Idrees, A ; Zaman, W. Q ; Abbas, Z ; Farooq, U ; Ali, M ; Yang, R ; Zeng, G ; Danish, M ; Gu, X ; Lyu, S ; Sharif University of Technology
Elsevier B.V
2021
Abstract
A novel catalyst of sulfidated iron-nickel supported on biochar (S-FeNi@BC) was synthesized to activate persulfate (PS) for the removal of trichloroethylene (TCE). A number of techniques including XRD, SEM, TEM, FTIR, BET and EDS were employed to characterize S-FeNi@BC. The influence of sulfur to iron ratio (S/F) on TCE removal was investigated by batch experiments and a higher TCE removal (98.4%) was achieved at 0.22/1 ratio of S/F in the PS/S-FeNi@BC oxidation system. A dominant role in iron species conversion was noticed by the addition of sulfur in FeNi@BC system. Significant enhancement in recycling of the dissolved and surface Fe(II) was confirmed which contributed to the generation of...
Mesoporous nanostructures of NiCo-LDH/ZnCo2O4 as an efficient electrocatalyst for oxygen evolution reaction
, Article Journal of Colloid and Interface Science ; Volume 604 , 2021 , Pages 832-843 ; 00219797 (ISSN) ; Shahrokhian, S ; Amini, M. K ; Sharif University of Technology
Academic Press Inc
2021
Abstract
Increasing energy demands for pollution-free and renewable energy technologies have stimulated intense research on the development of inexpensive, highly efficient, and stable non-noble metal electrocatalysts for oxygen evolution reaction (OER). In this study, a superior OER performance was achieved using a tri-metallic (Zn, Co, Ni) high-performance electrocatalyst. We successfully fabricated a peony-flower-like hierarchical ZnCo2O4 through an additive-free hydrothermal reaction followed by heat treatment. Then NiCo-LDH (layered double hydroxides) nano-flakes was electrodeposited on the ZnCo2O4/GCE surface to prepare NiCo-LDH/ZnCo2O4/GCE which was used as electrode for OER. The structure and...
Construction of Pt nanoparticle-decorated graphene nanosheets and carbon nanospheres nanocomposite-modified electrodes: Application to ultrasensitive electrochemical determination of cefepime
, Article RSC Advances ; Volume 4, Issue 15 , 2014 , Pages 7786-7794 ; ISSN: 20462069 ; Hosseini Nassab, N ; Ghalkhani, M ; Sharif University of Technology
Abstract
A novel ultrasensitive modified electrode was fabricated with a graphene nanosheets and carbon nanospheres (GNS-CNS)-based nanocomposite film as a powerful platform. Pt nanoparticles (PtNPs) were simply electrodeposited onto the GNS-CNS-coated glassy carbon electrode creating a PtNPs/GNS-CNS hybrid nanocomposite modified electrode. Scanning electron microscopy, energy dispersive X-ray spectroscopy and linear sweep voltammetry (LSV) techniques were used for the characterization of the prepared modified electrode. The results of investigation of electrochemical response characteristics of cefepime (CP) revealed a considerable improvement in the oxidation peak current of CP on PtNPs/GNS-CNS/GCE...
Nickel-cobalt layered double hydroxide ultrathin nanosheets coated on reduced graphene oxide nonosheets/nickel foam for high performance asymmetric supercapacitors
, Article International Journal of Hydrogen Energy ; 2017 ; 03603199 (ISSN) ; Rahimi, S ; Mohammadi, R ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Here in, for the first time, we report a new and simple procedure for preparing reduced graphene oxide/nickel-cobalt double layered hydroxide composite on the nickel foam (Ni-Co LDH/rGO/NF) via a fast and simple two-step electrochemical method including potentiostatic routes in the presence of CTAB as a cationic surfactant. Graphene oxide coated nickel foam prepared by simple immersion method. After that, the prepared electrode reduced electrochemically to obtain rGO/NF electrode. Finally, the rGO/NF electrode was used as cathode for electrodeposition of Ni-Co LDH in the presence of CTAB as cationic surfactant. The prepared electrodes were characterized by field emission scanning electron...
Vertically standing Cu2O nanosheets promoted flower-like PtPd nanostructures supported on reduced graphene oxide for methanol electro-oxidation
, Article Electrochimica Acta ; Volume 259 , 2018 , Pages 36-47 ; 00134686 (ISSN) ; Rezaee, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The present study reports a simple electrochemical approach to the fabrication of a new nanocomposite containing PtPd nanoflowers (NFs) promoted with two-dimensional (2D) nanosheets (NSs) structure cuprous oxide (Cu2O) supported on reduced graphene oxide (rGO) (PtPd-NFs/Cu2O-NSs/rGO). Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectra, Raman spectroscopy, and energy dispersive X-ray spectroscopy are used for characterization of the PtPd-NPs/Cu2O-NPs/rGO. SEM images showed that vertical-standing arrays of Cu2O with an edge length up to 1 μm and thickness of about 20 nm are electrodeposited on the surface of rGO film. Also, PtPd needle-like NFs with visible and...
Nickel-cobalt layered double hydroxide ultrathin nanosheets coated on reduced graphene oxide nonosheets/nickel foam for high performance asymmetric supercapacitors
, Article International Journal of Hydrogen Energy ; Volume 43, Issue 4 , 2018 , Pages 2256-2267 ; 03603199 (ISSN) ; Rahimi, S ; Mohammadi, R ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Here in, for the first time, we report a new and simple procedure for preparing reduced graphene oxide/nickel-cobalt double layered hydroxide composite on the nickel foam (Ni-Co LDH/rGO/NF) via a fast and simple two-step electrochemical method including potentiostatic routes in the presence of CTAB as a cationic surfactant. Graphene oxide coated nickel foam prepared by simple immersion method. After that, the prepared electrode reduced electrochemically to obtain rGO/NF electrode. Finally, the rGO/NF electrode was used as cathode for electrodeposition of Ni-Co LDH in the presence of CTAB as cationic surfactant. The prepared electrodes were characterized by field emission scanning electron...
Fabrication of a sensitive and fast response electrochemical glucose sensing platform based on co-based metal-organic frameworks obtained from rapid in situ conversion of electrodeposited cobalt hydroxide intermediates
, Article Talanta ; Volume 210 , 2020 ; Ezzati, M ; Hosseini, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In this study, for the first time, we reported a fast and facile three-step in situ strategy for direct controllable growth of the Co3(BTC)2 MOFs thin films on the GCE, through the rapid conversion of the electrodeposited Co(OH)2 nano-flakes on rGO/GCE, to crystalline rectangular bar-shape structures of MOFs. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and elemental mapping analysis used to the structural and morphological characterization of the well-synthesized MOFs. The as-prepared Co3(BTC)2 MOFs were used to construct a non-enzymatic sensing platform for determining the glucose...
Phase formation and microstructural evolution during sintering of Al-Zn-Mg-Cu alloys
, Article Powder Metallurgy ; Volume 53, Issue 1 , 2010 , Pages 62-70 ; 00325899 (ISSN) ; Simchi, A ; Gierl, C ; Sharif University of Technology
2010
Abstract
Al–5·6Zn, Al–5·6Zn–2·5Mg and Al–5·6Zn–2·5Mg–1·6Cu (wt-%) powder blends were compacted at 350 MPa and sintered in nitrogen at different temperatures to study microstructural evolution during sintering. Densification, dimensional changes and mechanical properties of the Al alloys were investigated. Microstructural analyses were performed by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and simultaneous thermal analysis (STA) in order to determine the temperature and chemical composition of the phases formed during sintering. It was shown that various liquids and intermetallic phases including Al0·71Zn0·29 at 438°C,...
L10 FePt Nanoparticles Processing with Applied Magnetic Field
, Article Journal of Inorganic and Organometallic Polymers and Materials ; Volume 23, Issue 4 , April , 2013 , Pages 881-887 ; 15741443 (ISSN) ; Khajehnezhad, A ; Dariani, R. S ; Akhavan, M ; Sharif University of Technology
2013
Abstract
Due to the strong magnetic anisotropy energy, the L10 FePt nanocrystals are considered as one of promising candidates for magnetic recording media with ultrahigh densities. The surfaces of Si and SiO2 wafers have been covered by FePt nanoparticles (NPs) and heated at 600 °C for 1 h to form the L10 phase. Bonding of NPs with the SiO2 surface in the presence of magnetic field during annealing process controls the L10 FePt NPs size and their uniform surface distribution. In the presence of perpendicular magnetic field to the surface, the size of NPs obtains up to 30 nm with coercivity of 5.8 kOe and in parallel magnetic field, the NPs size reaches to 45 nm with coercivity of 2.9 kOe. These...
Growth and characterization of TixNi1-x shape memory thin films using simultaneous sputter deposition from separate elemental targets
, Article Thin Solid Films ; Volume 491, Issue 1-2 , 2005 , Pages 190-196 ; 00406090 (ISSN) ; Sadrnezhaad, S. K ; Yates, K. A ; Barber, Z. H ; Sharif University of Technology
2005
Abstract
The fabrication of TixNi1-x shape memory films using simultaneous magnetron sputtering from two separate, elemental targets was investigated. The films were deposited at room temperature and then annealed at 500 °C to achieve the shape memory effect. The influence of sputtering parameters such as power ratio to the targets (to control the composition) and Ar gas pressure (to control the film structure) were studied. It was found that the Ar gas pressure had a critical influence on the shape memory effect of the films. Characterization of the films was carried out by energy dispersive X-ray spectroscopy in a scanning electron microscope (to measure the film composition and uniformity), in...
Binary and ternary NiTi-based shape memory films deposited by simultaneous sputter deposition from elemental targets
, Article Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films ; Volume 23, Issue 5 , 2005 , Pages 1425-1429 ; 07342101 (ISSN) ; Cao, Y. Z ; Sadrnezhaad, S. K ; Barber, Z. H ; Sharif University of Technology
2005
Abstract
The most challenging requirement for depositing NiTi-based shape memory thin films is the control of film composition because a small deviation can strongly shift the transformation temperatures. This article presents a technique to control film composition via adjustment of the power supplied to the targets during simultaneous sputter deposition from separate Ni, Ti, and X (e.g., Hf) targets. After optimization of sputter parameters such as working gas pressure, target-substrate distance, and target power ratio, binary Ni100-x Tix thin films were fabricated and characterized by energy dispersive x-ray spectroscopy in a scanning electron microscope (to measure the film composition and...
Interaction between refractory crucible materials and the melted NiTi shape-memory alloy
, Article Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science ; Volume 36, Issue 3 , 2005 , Pages 395-403 ; 10735615 (ISSN) ; Badakhshan Raz, S ; Sharif University of Technology
Minerals, Metals and Materials Society
2005
Abstract
Attempts have been made to quantify the amount of contaminants absorbed by liquid metal from commercial ZrO2-, Al2O3-, and SiC-base crucibles used for vacuum melting of Ni-45 wt pet Ti alloy. The molten alloy was held under vacuum for 90 minutes at 1450°C to become homogenized. Reactions between the liquid metal and the crucible were investigated by visual observation, chemical analysis, scanning electron microscopy (SEM) image processing, and X-ray mapping. The relative degree of contamination declined in the following sequence: commercially pure SiC > SiC-5 wt pct Al2O3-5 wt pet SiO2] > slurry cast alumina > recrystallized alumina > zircon type A > oxygen deficient high-purity zirconia....
Monodentate palladium(0)-[60]fullerene complexes of diphosphine ligands as efficient and sustainable nanocatalysts for the Mizoroki-Heck coupling reaction of aryl chlorides
, Article New Journal of Chemistry ; Volume 41, Issue 18 , 2017 , Pages 9701-9709 ; 11440546 (ISSN) ; Hosseinzadeh, M ; Zarepour Jevinani, M ; Ghanbari, B ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
Two mononuclear coordination complexes of fullerene[60] with Pd(dba)2 (dba = dibenzylideneacetone), [(η2-C60)Pd(Ph2P(CH2)2PPh2C(H)C(O)R)2] (R = C10H7 (1), C6H4Cl (2)), have been prepared using a simple procedure to explore new directions in palladium catalysis and nanocarbon chemistry. The palladium(0)-[60]fullerene complexes incorporating unsymmetrical phosphorus ylides have been characterized by 1H, 13C and 31P NMR spectroscopic methods and other conventional techniques such as IR, TGA, SEM, ICP-OES, EDX and TEM analysis. Attributed to the enhanced dispersity and uniform size of the Pd nanoparticles with phosphine-functionalized fullerenes, the prepared catalysts exhibited comparable...
Synthesis of NiAl-TiC composites from elemental powders by volume combustion method
, Article Materials Science and Technology (United Kingdom) ; Volume 35, Issue 7 , 2019 , Pages 831-838 ; 02670836 (ISSN) ; Minagar, A ; Naseri, G ; Bahmani, A ; Malekan, M ; Sharif University of Technology
Taylor and Francis Ltd
2019
Abstract
NiAl-TiC composites were synthesised by volume combustion (VC) method from elemental powders to improve the mechanical properties and high temperature performance of nickel aluminide. Synthesised specimens with porous nature were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analysis. XRD results showed that NiAl was dominant phase and other phases like Al 3 Ni 2 (in NiAl + 5 wt-% TiC, NiAl + 10 wt-% TiC specimens) and AlNi 3 (in equimolar NiAl-TiC) were present in specimens. Synthesised specimens of NiAl, NiAl + 5 wt-% TiC, NiAl + 10 wt-% TiC, NiAl + 15 wt-% TiC and equimolar NiAl-TiC achieved Vickers...
Toward higher extraction and enrichment factors via a double-reservoirs microfluidic device as a micro-extractive platform
, Article Journal of Separation Science ; Volume 42, Issue 18 , 2019 , Pages 2985-2992 ; 16159306 (ISSN) ; Baraazandeh, M ; Bagheri, H ; Sharif University of Technology
Wiley-VCH Verlag
2019
Abstract
In this study, firstly, a double-reservoir and switchable prototype of a micro-chip along with the respective holders were fabricated. A cyclic desorption process using microliter volume of organic solvent was adopted to prevent any outdoor contamination. As extractive phases, two identical sheets of electrospun polyamide/polypyrrole/titania nanofibers were synthesized using core–shell electro-spinning technique and utilized for determination of memantine in plasma samples. Field emission scanning electron microscopy images showed a high degree of porosity and homogeneity throughout the sheet structure. Also, energy dispersive X-ray analysis confirmed the presence of titania, while the...
Ugi four-component assembly process: An efficient approach for one-pot multifunctionalization of nanographene oxide in water and its application in lipase immobilization
, Article Chemistry of Materials ; Volume 28, Issue 9 , 2016 , Pages 3004-3016 ; 08974756 (ISSN) ; Akhavan, O ; Hashemi, E ; Shamsara, M ; Sharif University of Technology
American Chemical Society
2016
Abstract
Graphene-based materials are revealing the leading edge of advanced technology for their exceptional physical and chemical properties. Chemical manipulation on graphene surface to tailor its unique properties and modify atomic structures is being actively pursued. Therefore, the discovery of robust and general protocols to anchor active functionality on graphene basal plane is still of great interest. Multicomponent reactions promise an enormous level of interest due to addressing both diversity and complexity in combinatorial synthesis, in which more than two starting compounds react to form a product derived from entire inputs. In this article, we present the first covalent...