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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...
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
Effect of Cysteine Substitutions on the Structural and Magnetic Properties of Fe3O4–Cysteine/RGO and Fe3O4/RGO–Cysteine Nanocomposites
, Article Journal of Superconductivity and Novel Magnetism ; 2018 ; 15571939 (ISSN) ; Mehrani, K ; Madaah Hosseini, H. R ; Zare, K ; Sharif University of Technology
Springer New York LLC
2018
Abstract
We synthesized by electrostatic self-assembly route in basic solution Fe3O4–cysteine/RGO and Fe3O4/RGO–cysteine nanocomposites. In this method, electrostatic interaction was created via negatively charged surface of the reduced graphene oxide and reduced graphene oxide–cysteine sheets and positively charged surface of the Fe3O4 and Fe3O4–Cys nanoparticles in aqueous solution. The structural and magnetic properties of the prepared samples were analyzed by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM), respectively. The dependences of magnetization as a function of...
HTS YBCO resonator configuration with a coplanar optimized flux concentrator strongly coupled to RF squid
, Article IEEE Transactions on Applied Superconductivity ; Volume 28, Issue 4 , 2018 ; 10518223 (ISSN) ; Shanehsazzadeh, F ; Mazdouri, B ; Fardmanesh, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
We developed a novel magnetic coupling module, formed of a monolayer superconducting flux concentrator that is integrated with a coplanar resonator, strongly coupled to high-temperature superconducting radio frequency superconducting quantum interference device (SQUID). Three types of resonators, including a long stripline resonator between the input loop and the pick-up loop of the flux concentrator, a complementary split ring resonator, and a spiral shape inside the input loop, are explored. The resonance quality factor of different patterns of these three types of the resonators, as well as their coupling to the SQUID, is evaluated using finite-element-method simulations. Several readout...
Effect of cysteine substitutions on the structural and magnetic properties of Fe3O4–Cysteine/RGO and Fe3O4/RGO–Cysteine nanocomposites
, Article Journal of Superconductivity and Novel Magnetism ; Volume 32, Issue 5 , 2019 , Pages 1299-1306 ; 15571939 (ISSN) ; Mehrani, K ; Madaah Hosseini , H. R ; Zare, K ; Sharif University of Technology
Springer New York LLC
2019
Abstract
We synthesized by electrostatic self-assembly route in basic solution Fe3O4–cysteine/RGO and Fe3O4/RGO–cysteine nanocomposites. In this method, electrostatic interaction was created via negatively charged surface of the reduced graphene oxide and reduced graphene oxide–cysteine sheets and positively charged surface of the Fe3O4 and Fe3O4–Cys nanoparticles in aqueous solution. The structural and magnetic properties of the prepared samples were analyzed by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM), respectively. The dependences of magnetization as a function of...
Optimization-based gravity-assisted calibration and axis alignment of 9-degrees of freedom inertial measurement unit without external equipment
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Volume 234, Issue 2 , 2020 , Pages 192-207 ; Salarieh, H ; Alasty, A ; Sharif University of Technology
SAGE Publications Ltd
2020
Abstract
Applicable in numerous fields, low-cost micro-electromechanical system inertial measurement units often require on-sight calibration by the end user due to the existence of systematic errors. A 9-degrees of freedom inertial measurement unit comprises a tri-axis accelerometer, a tri-axis gyroscope, and a tri-axis magnetometer. Various proposed multi-position calibration methods can calibrate tri-axis accelerometers and magnetometers to a degree. Yet the full calibration of a tri-axis gyroscope and axis alignment of all the sensors still often requires equipment such as a rate table to generate a priori known angular velocities and attitudes or relies on the disturbance-prone magnetometer...
Integrated Navigation for Attitude and Orbit Estimation of Nano satellite with Online Calibration
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor) ; Alasti, Aria (Supervisor) ; Jalili, Hadi (Co-Supervisor)
Abstract
In this study, integrated navigation for attitude and orbit estimation of nanosatellite with online magnetometer calibration is derived. This algorithm has been developed based on the Extended Kalman Filter and Unscented Kalman Filter and the unknown magnetometer’s parameters (such as bias vector and scale factor orthogonal matrix and non-orthognal misallignmet matrix) are estimated in order to calibration of this sensor. In order to determine the location and orientation of the satellite, many different algorithms have been developed which have the ability to determine the location without the need for GPS sensor; it is necessary to be calibrated and ensure proper performance of these...
Development of an Online Calibration Algorithm for Three Axis-Magnetic Sensor through Data Fusion Techniques
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor)
Abstract
There are challenges in controlling and guidance of vehicles which makes it necessary to have true information about the position, velocity, and orientation of the system. This issue is severe to some extent when a UAV is the object to be controlled. The navigation system is responsible for supplying the mentioned information which is usually accompanied with some errors. Therefore, threre are a wide range of algorithms developed for omitting these errors leading to a well-calibrated navigation system. One of the precise and reliable calibration method is based on the data fusion of intertial navigation sensors and magnetometer measurements. As the obtained data via magnetometers are usually...
Controlling the Position of the Wheeled Robot by Mobile Phone Sensors
, M.Sc. Thesis Sharif University of Technology ; Pour Mohammad Namvar, Mehrzad (Supervisor)
Abstract
This thesis deals with the construction of software tools necessary to calculate the position and orientation of the robot. The aim of this project is to use accelerometer, gyroscope, magnetometer and GPS sensors; Determine the position and orientation of the robot where the mobile phone is located. The proposed sensors are used to measure acceleration, angular velocity and magnetic field in 3 axes, respectively. GPS is also a system for calculating the position using signals received from satellites. To do this, an Android application has been designed and written in Java. The sensor information is collected by the software designed in the mobile phone and after proper coding is sent to a...
On the effect of cooling rate during melt spinning of FINEMET ribbons
, Article Nanoscale ; Volume 5, Issue 16 , 2013 , Pages 7520-7527 ; 20403364 (ISSN) ; Hosseini, H. R. M ; Davami, P ; Ostadhossein, F ; Song, M ; Gjoka, M ; Sharif University of Technology
2013
Abstract
The effect of quenching wheel speed on the structure and Curie temperature of Fe73.5Si13.5B9Nb3Cu1 alloy has been investigated using X-ray diffraction, differential scanning calorimetry, transition electron microscopy and a SQUID magnetometer. Ribbons were melt-spun at different wheel speeds and then were annealed to nucleate nano crystals embedded in the amorphous matrix. The results indicated that the thickness of the ribbons was inversely proportional to the wheel speed following the power law of the type t ∝ Vs -1.231. DSC and XRD results showed that at higher wheel speeds the greater potential energy triggers the formation of Fe (Si) crystallites and thus, increases the crystallinity....
Effects of Ce–Co substitution on structural, magnetic and dielectric properties of M-type barium hexaferrite nanoparticles synthetized by sol–gel auto-combustion route
, Article Journal of Materials Science: Materials in Electronics ; Volume 26, Issue 4 , 2015 , Pages 2134-2144 ; 09574522 (ISSN) ; Nemati, A ; Sharif University of Technology
Springer New York LLC
2015
Abstract
M-type Ce–Co substituted barium hexaferrite nanoparticles were synthesized by sol–gel auto-combustion route. The general formula of ferrites was Ba1−xCexFe12−xCoxO19 in which the x was considered to be: x = 0, 0.1, 0.2, and 0.3. The formed phases in the samples were characterized by using X-ray diffraction, Fourier transform infrared spectroscopy, Mössbauer spectroscopy and vibrating sample magnetometer. The results indicated that an increase in substitutional ion amount caused to decrease vibration frequencies of Fe–O band in the tetrahedral site due to the substitution of heavier Co2+ ion for Fe3+ ion in the tetrahedral site. Moreover, some of Ce3+ ions was transformed to Ce4+ and...
Solvent-free preparation of copper ferrite microspheres composed of nanorods using a new coordination compound as precursor
, Article Journal of Materials Science: Materials in Electronics ; Volume 28, Issue 16 , 2017 , Pages 11682-11688 ; 09574522 (ISSN) ; Mohandes, F ; Ahmadian Fard Fini, S ; Sobhani, A ; Shabani Armaki, N ; Salavati Niasari, M ; Sharif University of Technology
Springer New York LLC
2017
Abstract
This work presents a simple solvent-free route based on solid-state thermal decomposition approach to synthesize magnetic copper ferrite (CuFe2O4) microspheres and copper ferrite/metal oxide composites. For this purpose, [Cu(en)3]3[Fe(ox)3]2 complex (where en = ethylenediamine and ox = oxalate) was introduced as a new single-source precursor. Ferromagnetic property of the nanostructures was determined by alternating gradient force magnetometer. The effect of different ligands and temperatures on the morphology of the products was investigated. Solid-state thermal decomposition of the precursor at different temperatures in the range of 400–800 °C led to the fabrication of magnetic copper...
Robust integrated orbit and attitude estimation using geophysical data
, Article Aerospace Science and Technology ; Volume 93 , 2019 ; 12709638 (ISSN) ; Sharif University of Technology
Elsevier Masson SAS
2019
Abstract
Geophysical information such as the Earth geomagnetic field and gravity gradient (GG) data can provide a basis for autonomous concurrent orbit and attitude estimation (COAE) of satellites in low earth orbits (LEO), as magnetometers and gravity gradiometer measurements are in general functions of time, position as well as the vehicle's orientation. While gradiometer has recently been investigated just for orbit estimation (OE), the current study is focused on COAE via only utility of the GG data. To this aim, observability conditions are analyzed, where the sensitivity of the proposed COAE approach with respect to various system and roto-translational elements is also examined. Considering...
Shielding factor enhancement method for Bi-stage active shield in SQUID-based magnetocardiography system
, Article 29th Iranian Conference on Electrical Engineering, ICEE 2021, 18 May 2021 through 20 May 2021 ; 2021 , Pages 129-133 ; 9781665433655 (ISBN) ; Esmaeili, F ; Shanehsazzadeh, F ; Fardmanesh, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
We proposed a simple method to enhance shielding factor of our previously proposed bi-stage active shield system employed in a SQUID-based magnetocardiography system. The additional proposed design is optimized for canceling the power-line magnetic interference field to provide a calmer magnetic environment for the bi-stage active shield. A 50 Hz cancellation coil is placed around the bi-stage shielding system which includes inner and outer coils designed for compensating low-frequency (0-0.1Hz) and high-frequency (0.1-100Hz) environmental magnetic noise, respectively. In this configuration, a SQUID magnetometer is located at the center of these coils. Considering that the power-line...
Shielding factor enhancement method for bi-stage active shield in SQUID-based magnetocardiography system
, Article 29th Iranian Conference on Electrical Engineering, ICEE 2021, 18 May 2021 through 20 May 2021 ; 2021 , Pages 129-133 ; 9781665433655 (ISBN) ; Esmaeili, F ; Shanehsazzadeh, F ; Fardmanesh, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
We proposed a simple method to enhance shielding factor of our previously proposed bi-stage active shield system employed in a SQUID-based magnetocardiography system. The additional proposed design is optimized for canceling the power-line magnetic interference field to provide a calmer magnetic environment for the bi-stage active shield. A 50 Hz cancellation coil is placed around the bi-stage shielding system which includes inner and outer coils designed for compensating low-frequency (0-0.1Hz) and high-frequency (0.1-100Hz) environmental magnetic noise, respectively. In this configuration, a SQUID magnetometer is located at the center of these coils. Considering that the power-line...
Magnetic/pH-sensitive κ-carrageenan/sodium alginate hydrogel nanocomposite beads: Preparation, swelling behavior, and drug delivery
, Article Journal of Biomaterials Science, Polymer Edition ; Vol. 25, issue. 17 , 2014 , p. 1891-1906 ; Rahmani, Z ; Karami, S ; Pourjavadi, A ; Sharif University of Technology
Abstract
This work describes the preparation of magnetic and pH-sensitive beads based on κ-carrageenan and sodium alginate for use as drug-targeting carriers. Physical cross-linking using K+/Ca2+ ions was applied to obtain ionic cross-linked magnetic hydrogel beads. The produced magnetite beads were thoroughly characterized by TEM, SEM/EDS, XRD, FTIR, and VSM techniques. While the water absorbency (WA) of magnetic beads was enhanced by increasing the weight ratio of κ-carrageenan, introducing magnetic nanoparticles caused a decrease in WA capacity from 15.4 to 6.3 g/g. Investigation on the swelling of the hydrogel beads in NaCl, KCl, and CaCl2 solutions revealed the disintegration of beads depending...
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...
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),...
A new non-linear algorithm for complete pre-flight calibration of magnetometers in the geomagnetic field domain
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Volume 223, Issue 6 , 2009 , Pages 729-739 ; 09544100 (ISSN) ; Pourtakdoust, S. H ; Samani, M ; Sharif University of Technology
2009
Abstract
A new algorithm for complete pre-flight calibration of triple magnetometers is developed. The traditional approach for calibrating these sensors are based on a cumbersome procedure called 'swing' that involves levelling and rotating the vehicle containing the magnetometers through a series of known headings. Application of such a procedure is difficult and costly. Recently, new approaches have been developed to calibrate magnetometers without the need of attitude information. Such methods are used mostly for the calibration of biases and scale factors. Additionally in situations where misalignment errors are also to be estimated, they are usually modelled as errors of a non-orthogonal frame...
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...