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vibrating-sample-magnetometer
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Design and Implementation of Vibrating Sample Magnetometer Based on Gradiometer RF SQUID
, M.Sc. Thesis Sharif University of Technology ; Fardmanesh, Mehdi (Supervisor)
Abstract
The aim of this project is design and implementation of the “gradiometer RF SQUID base Vibrating Sample Magnetometer (VSM)”. Different sections of the system have been designed such as pick up coils, vibration system and electronic circuits. The piezoelectric crystal has been concerned for vibration system. At the first step, we have implemented the basic VSM system. In the basic system, voltage induces in two series opposite pick up coils and its output is recognizable via electronic circuits. At the second phase of the project, the electronic circuits of basic VSM system have been replaced with the RF SQUID gradiometer and its electronic circuits. Afterwards, the sensitivity and the gain...
Solution Combustion Synthesis of Spinel-type (Cu,Co) 3O4 Nanopowder
, M.Sc. Thesis Sharif University of Technology ; Yoozbashizadeh, Hossein (Supervisor)
Abstract
In this study, nano-powders of copper-cobalt spinel (CuCo2O4) were fabricated by solution combustion synthesis (SCS) of Cu and Co nitrates with urea, glycine,acid citric and alanine. The method involved exothermic decomposition of viscous liquid nitrates and the fuel. Products which were synthesized by using this fuels contained less impurity constituents. Duo to low purity, other factors which have influence on synthesis process investigated and observed that pH have key role on process. X-ray diffraction (XRD) patterns gave crystal structure and the existing phases. Particle size distribution and morphology changes were studied by dynamic light scattering (DLS) and field emission scanning...
Critical Current Density Optimization of High-T_c Superconductor
, M.Sc. Thesis Sharif University of Technology ; Fardmanesh, Mehdi (Supervisor)
Abstract
Fabrication of bulk superconductors with high critical current density widely has been studied because they have many applications, for example, Fault Current Limiter (SFCL), Superconducting Magnetic Energy Storage (SMES), and magnetic levitation. Providing pinning center by addings impurity into superconductor is usual and simple solution for increasing the superconductor critical current density. In this project we have fabricated superconductor YBCO bulk and optimized its critical current density. There are two major stream in this thesis, first design of Vibrating System Magnetization (VSM) for critical current measurements and then fabrication of YBCO bulk and optimization of its...
The effects of thickness on magnetic properties of FeCuNbSiB sputtered thin films
, Article Scientia Iranica ; Volume 24, Issue 6 , 2017 , Pages 3521-3525 ; 10263098 (ISSN) ; Celegato, F ; Tiberto, P ; Castellero, A ; Baricco, M ; Hosseini, H. R. M ; Sharif University of Technology
Abstract
Thin films of Fe73.1Cu1Nb3.1Si14.7B8.2 alloy with 200, 500, and 800 nm thicknesses have been deposited by RF sputtering. Their magnetic properties have been characterized using Alternating Gradient Field Magnetometer (AGFM) and Vibrating Sample Magnetometer (VSM). The effects of residual stresses investigated by nanoindentation experiments were conducted on the as-deposited samples. It is observed that the coercivity of as-deposited films is inversely proportional to the thickness in relation with the residual stress induced during sputtering. © 2017 Sharif University of Technology. All rights reserved
Synthesis of magnetic ions-doped QDs Synthesized Via a facial aqueous solution method for Optical/MR dual-modality imaging applications
, Article Journal of Fluorescence ; Volume 31, Issue 3 , 2021 , Pages 897-906 ; 10530509 (ISSN) ; Zare, H ; Shahedi, Z ; Fazaeli, Y ; Rahighi, R ; Sharif University of Technology
Springer
2021
Abstract
This research reports the preparation and examination of Cadmium Telluride (CdTe) Quantum Dots and doping CdTe QDs with Europium (Eu), Gadolinium (Gd), and Manganese (Mn) prepared in aqueous solution using TGA as a capping agent. Magnetic QDs (MQDs) are important agents for fluorescence (FL) /magnetic resonance (MR) dual-modal imaging due to their excellent optical and magnetic properties. Herein, the chemical bonds, structural, fluorescence, and magnetized properties of CdTe QDs and effect of Mn, Eu, and Gd ions doping on their properties were examined by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTM), Energy-dispersive X-ray spectroscopy (EDX),...
Synthesis, morpho-structural properties, and catalytic performances of Pt-APA@Fe3O4/GO nanocomposite based on magnetical graphene in C–C coupling reactions and photoinactivation of E. coli
, Article Journal of Nanoparticle Research ; Volume 23, Issue 8 , 2021 ; 13880764 (ISSN) ; Sabounchei, S. J ; Yousefi, A ; Akhavan, O ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Herein, a novel Pt-APA composite (APA = pyridinium bromide salt) based on magnetic graphene oxide was synthesized and used as an effective catalyst. In this way, Fe3O4 nanoparticles are grown on graphene oxide (GO) nanosheets by a simple and practical method which creates a unique nanostructure (Fe3O4/GO) through dispersing uniformly among graphene nanosheets. The resulted Pt-APA composite was obtained via adding PtCl2 to an ethanol solution of Fe3O4/GO and α-keto stabilized pyridinium ylide in related conditions. The synthesized nanocomposite structure was identified using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive...
Study of nanocrystallization in FINEMET alloy by active screen plasma nitriding
, Article Journal of Alloys and Compounds ; Volume 491, Issue 1-2 , 2010 , Pages 487-494 ; 09258388 (ISSN) ; Madaah Hosseini, H. R ; Memarzadeh Lotfabad, E ; Roostaie, S ; Sharif University of Technology
2010
Abstract
The nanocrystallization process of amorphous Fe73.5Si13.5B9Nb3Cu 1 was investigated by active screen plasma nitriding (ASPN) treatment at temperatures ranging from 410 °C to 560 °C for 3 h in two gas mixtures of 75% N2-25% H2 and 25% N2-75% H2 at 5 mbar atmosphere. The amorphous ribbons were then annealed under vacuum at the same time and temperatures mentioned above. The structure of the samples was analyzed using various techniques such as X-ray diffraction (XRD), atomic force microscopy (AFM) and differential scanning calorimetry (DSC). Microhardness measurements, electrical resistivity and Vibrating Sample Magnetometer (VSM) were used to study mechanical, electrical and magnetic...
Study of molecular conformation and activity-related properties of lipase immobilized onto core-shell structured polyacrylic acid-coated magnetic silica nanocomposite particles
, Article Langmuir ; Volume 32, Issue 13 , 2016 , Pages 3242-3252 ; 07437463 (ISSN) ; Kazemeini, M ; Singh, G ; Arpanaei, A ; Sharif University of Technology
American Chemical Society
Abstract
A facile approach for the preparation of core-shell structured poly(acrylic acid) (PAA)-coated Fe3O4 cluster@SiO2 nanocomposite particles as the support materials for the lipase immobilization is reported. Low- or high-molecular-weight (1800 and 100 000, respectively) PAA molecules were covalently attached onto the surface of amine-functionalized magnetic silica nanoacomposite particles. The successful preparation of particles were verified by scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential measurement, and Fourier-transform infrared (FTIR) techniques. Once lipase is covalently...
Structural Rietveld refinement and magnetic features of prosademium (Pr) doped Cu nanocrystalline spinel ferrites
, Article Ceramics International ; Volume 45, Issue 8 , 2019 , Pages 10187-10195 ; 02728842 (ISSN) ; Babar, M ; Qamar, S ; ur Rehman, Z ; Azhar Khan, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Pr doped spinel nanoferrites having following composition Cu Pr x Fe 2-x O 4 (x = 0, 0.25, 0.50, 0.75, 1.00) were synthesized using sol-gel route. Prosademium (Pr) which is a rare earth metal was doped to tailor the properties of the Cu spinel nanoferrites. Characterization tools such as FTIR, XRD, FESEM and VSM were employed to investigate the phase, absorption bands, structure, microstructure and magnetic properties. FTIR was used to see the absorption bands and force constants of the Pr doped Cu spinel nanoferrites. Crystallite size, lattice parameters, cell volume and micro strains were determined from XRD data. Bulk density, X-ray density and porosity of the Pr doped Cu spinel...
Structural and magnetic study of active screen plasma nitrided Fe 73.5Si13.5B9Nb3Cu1and Fe77Si11B9Nb2.4Cu0.6 ribbons
, Article Scientia Iranica ; Volume 17, Issue 1 F , 2010 , Pages 12-22 ; 10263098 (ISSN) ; Madaah Hosseini, H.R ; Asghari Shivaee, H ; Roostaie, S ; Sharif University of Technology
2010
Abstract
The comparative study of Active Screen Plasma Nitriding (ASPN) treatment of two Finemet-type alloys with the compositions of Fe73.5Si 13.5B9Nb3Cu1 and Fe 77Si11B9Nb2.4Cu0.6 was investigated in different temperatures ranging from 410°C to 56°C. Differential Scanning Calorimetry (DSC), X-Ray Diffractometery (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), electrical resistivity, microhardness measurements and magnetic characterization by a Vibrating Sample Magnetometer (VSM) were utilized to characterize the treated samples. The comparison of the DSC data for the alloys suggested that the smaller amount of Nb as a growth inhibitor shifted the crystallization...
Structural and magnetic evaluations of rare-earths (Tb, Pr, Ce, Gd, Y)-doped spinel ferrites for high frequency and switching applications
, Article Journal of Materials Science: Materials in Electronics ; Volume 32, Issue 6 , 2021 , Pages 7692-7703 ; 09574522 (ISSN) ; Akhtar, M. N ; Baqir, M. A ; Ahmad, A ; Khallidoon, M. U ; Farhan, M ; Khan, M. A ; Sharif University of Technology
Springer
2021
Abstract
NiZn nanoferrites doped with rare-earth cations having stoichiometric composition such as Ni0.5Zn0.5R0.02Fe1.98O4 (R = Tb, Pr, Ce, Gd, Y) were prepared by sol–gel technique. The same amount of Ni and Zn with constant ratio of different rare-earths ions were doped to investigate the variations in the properties. X-ray diffraction (XRD), Field emission electron microscope (FESEM), and vibrating sample magnetometer (VSM) were used to investigate the structure, morphology, and magnetic properties of rare-earth doped NiZn nanoferrites, respectively. X-ray density, bulk density, and porosity were also calculated. Phase, crystallite size, structure, d-spacing, lattice parameter, micro strain, and...
Structural and magnetic evaluations of rare-earths (Tb, Pr, Ce, Gd, Y)-doped spinel ferrites for high frequency and switching applications
, Article Journal of Materials Science: Materials in Electronics ; Volume 32, Issue 6 , 2021 , Pages 7692-7703 ; 09574522 (ISSN) ; Akhtar, M. N ; Baqir, M. A ; Ahmad, A ; Khallidoon, M. U ; Farhan, M ; Khan, M. A ; Sharif University of Technology
Springer
2021
Abstract
NiZn nanoferrites doped with rare-earth cations having stoichiometric composition such as Ni0.5Zn0.5R0.02Fe1.98O4 (R = Tb, Pr, Ce, Gd, Y) were prepared by sol–gel technique. The same amount of Ni and Zn with constant ratio of different rare-earths ions were doped to investigate the variations in the properties. X-ray diffraction (XRD), Field emission electron microscope (FESEM), and vibrating sample magnetometer (VSM) were used to investigate the structure, morphology, and magnetic properties of rare-earth doped NiZn nanoferrites, respectively. X-ray density, bulk density, and porosity were also calculated. Phase, crystallite size, structure, d-spacing, lattice parameter, micro strain, and...
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....
Preparation, magnetic properties, and photocatalytic performance under natural daylight irradiation of Fe3O4-ZnO core/shell nanoparticles designed on reduced go platelet
, Article Materials Science in Semiconductor Processing ; Volume 72 , 2017 , Pages 85-92 ; 13698001 (ISSN) ; Baghshahi, S ; Nemati, A ; Mahmoodi, M ; Sharif University of Technology
Abstract
Ternary mesoporous nanocomposites of RGO/Fe3O4-ZnO were prepared successfully via hydrothermal technique. Fe3O4-ZnO core/shell nanoparticles were decorated on the surface of reduced graphene oxide platelet to improve charge separation efficiency and magnetic properties. The phase, microstructure and specific surface area of the prepared samples were determined via X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy/selected area electron diffraction (TEM/SAED) and Brunauer–Emmett–Teller (BET) techniques. A vibrating sample magnetometer (VSM) was used for recording the magnetization hysteresis curves. The methylene blue (MB)...
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...
Phase formation and change of magnetic properties in mechanical alloyed Ni0.5Co0.5Fe2O4 by annealing
, Article Journal of Magnetism and Magnetic Materials ; Volume 322, Issue 1 , 2010 , Pages 56-59 ; 03048853 (ISSN) ; Yoozbashizadeh, H ; Yourdkhani, A ; Mohammadi, M ; Sharif University of Technology
Abstract
The effects of milling time and annealing temperature on phase formation, microstructure and magnetic properties of nickel-cobalt ferrite synthesized from oxide precursors by mechanical alloying were studied. The study of milling time effects on phase formation of milled materials showed that if milling continues up to 55 h, single phase nano-sized nickel-cobalt ferrite is obtained. Also, magnetic properties of powders versus milling time and annealing at different temperatures extensively changed, so that annealing at 1200 °C increased the magnetization saturation of the as-milled powder from 15.1 to 53.6 emu/g. X-ray powder diffraction technique (XRD) with Cu-Ka radiation was employed for...
Performance of silver nanoparticle fixed on magnetic iron nanoparticles (Fe3O4−Ag) in water disinfection
, Article Micro and Nano Letters ; Volume 13, Issue 4 , April , 2018 , Pages 436-441 ; 17500443 (ISSN) ; Hassani, A. H ; Ahmad Panahi, H ; Borghei, M ; Sharif University of Technology
Institution of Engineering and Technology
2018
Abstract
Microbial contamination poses a serious threat to human health. The evaluation of alternative systems and their reliability for the treatment of water is essential. In this work, a new method for the deposit of more silver nanoparticles (AgNPs) on the external surface of Fe3O4 nanoparticles is presented. Fe3O4 nanoparticles were synthesised by chemical co-precipitation and were modified in two stages using 3-mercaptopropyl trimethoxysilane and grafting allyl glycidyl ether and N, N-dimethylacrylamide. Then, AgNPs were loaded onto the modified Fe3O4 to be used for water disinfection. The resulting nanoparticles were characterised by transmission electron microscopy, X-ray powder diffraction,...
Optimized design and implementation of low-cost, sensitive and versatile vibrating sample magnetometer
, Article ICEE 2012 - 20th Iranian Conference on Electrical Engineering, 15 May 2012 through 17 May 2012 ; May , 2012 , Pages 202-205 ; 9781467311489 (ISBN) ; Khiabani, S ; Sarreshtedari, F ; Fardmanesh, M ; Sharif University of Technology
2012
Abstract
Geometry of different electromagnetic parts of Vibrating Sample Magnetometer (VSM) is a major factor of VSM output voltage. In this paper design, geometry optimization and implementation of a sensitive, versatile and relatively inexpensive VSM system has been described. Considering all effective geometrical parameters in the system output voltage, the induced voltage in the pick-up coils has been obtained analytically and the geometry of the pick-up coils has been optimized for maximum output induced voltage. Two opposite series of pick-up coils, piezoelectric based vibration system and required electronic circuits have been designed and the VSM system has been implemented. The implemented...
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...
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....