Flexible magnetic membranes based on bacterial cellulose and its evaluation as electromagnetic interference shielding material
MetadataShow full item record
Flexible magnetic membranes with high proportion of magnetite were successfully prepared by previous impregnation of the never dried bacterial cellulose pellicles with ferric chloride followed by reduction with sodium bisulfite and alkaline treatment for magnetite precipitation. Membranes were characterized by Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating magnetometer, field emission scanning electron microscopy (FEG-SEM) and impedance spectroscopy. Microwave properties of these membranes were investigated in the X-band (8.2 to 12.4 GHz). FEG-SEM micrographs show an effective coverage of the BC nanofibers by Fe 3O4 nanoparticles. Membranes with up to 75% in weight of particles have been prepared after 60 min of reaction. Magnetite nanoparticles in the form of aggregates well adhered to the BC fibers were observed by SEM. The average crystal sizes of the magnetic particles were in the range of 10 ± 1 to 13 ± 1 nm (estimated by XRD). The magnetic particles in the BC pellicles presented superparamagnetic behavior with a saturation magnetization in the range of 60 emu g- 1 and coercive force around 15 Oe. These magnetic pellicles also displayed high electrical permittivity and a potential application as microwave absorber materials. © 2013 Elsevier B.V.
How to cite this document
Showing items related by title, author, creator and subject.
Canesin, C. A. ; Gonçalves, F. A S ; Leandro, E. ; Pinto, J. O P (SPEEDAM 2008 - International Symposium on Power Electronics, Electrical Drives, Automation and Motion, 2008) [Trabalho apresentado em evento]This paper is based on the analysis and implementation of a new drive system applied to refrigeration systems, complying with the restrictions imposed by the IEC standards (Harmonic/Flicker/EMI-Electromagnetic Interference ...
De Souza, Flávio Queiroz ; Oki, Nobuo (Proceedings - SBCCI2011: 24th Symposium on Integrated Circuits and Systems Design, 2011) [Trabalho apresentado em evento]In this paper, the susceptibility of a current-mode bandgap voltage reference to electromagnetic interference (EMI) superimposed to the power supply is investigated by simulation. Designed for AMS 0.35 CMOS process, the ...
A simplified method for determining the high frequency induction motor equivalent electrical circuit parameters to be used in EMI effect Riehl, Rudolf Ribeiro ; Ruppert Filho, Ernesto (Proceeding of International Conference on Electrical Machines and Systems, ICEMS 2007, 2007) [Trabalho apresentado em evento]The aim of this paper is to present a simple method for determining the high frequency parameters of a three-phase induction motor to be used in studies involving variable speed drives with PWM three-phase inverters, in ...