TAILIEUCHUNG - Absorption of electromagnetic waves by Fe3O4 paraffin composite materials
The results indicated a large dielectric loss and strong thickness dependence of absorption capacity. The maximum absorption coefficient (RL) is of order dB, corresponding to the achieved absorbance of for the mm of sample thickness. The experimental results are consisted with our simulation calculation. | Communications in Physics, Vol. 29, No. 1 (2019), pp. 63-69 DOI: ABSORPTION OF ELECTROMAGNETIC WAVES BY Fe3 O4 /PARAFFIN COMPOSITE MATERIALS NGUYEN THI MINH HONG1,† , NGUYEN VAN DUY1 , NGUYEN DANG CO1 , BUI DINH TU1 AND PHAM DUC THANG1,2 1 Faculty of Engineering Physics and Nanotechnology, VNU University of Engineering and Technology, Building E3, 144 Xuan Thuy, Cau Giay, Hanoi, Vietnam 2 Key-laboratory for Micro and Nanotechnology, VNU University of Engineering and Technology, Building E3, 144 Xuan Thuy, Cau Giay, Hanoi, Vietnam † E-mail: minhhong3110@ Received 17 November 2018 Accepted for publication 15 January 2019 Published 15 February 2019 Abstract. Electromagnetic pollution in general and the harmful effects of microwave radiation in particular on environment is currently in the urgent stage. To eliminate the effect of electromagnetic energy the most common methods relies on the use of absorbing materials with large absorption capacities in wide frequency band. In this paper, we investigate the capability of absorption of electromagnetic waves of Fe3 O4 nanoparticles in paraffin basis. The Fe3 O4 /paraffin composite materials were prepared with a weight ratio of 35%/65%. The dielectric constant (εr ) and the magnetic permeability (µr ) in the frequency ( f ) range from 8 to 18 GHz were measured for various sample thicknesses. The results indicated a large dielectric loss and strong thickness dependence of absorption capacity. The maximum absorption coefficient (RL) is of order dB, corresponding to the achieved absorbance of for the mm of sample thickness. The experimental results are consisted with our simulation calculation. Keywords: absorbant material, electromagnetic wave absorption. Classification numbers: ; . I. INTRODUCTION Recently novel technologies in the field of telecommunications have attracted a considerable interest of scientists. However, the development and .
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