Comments on "Energy-transport velocity in electromagnetic waves" and "A classical electromagnetic wave paradox"

Composites made from E-glass/epoxy or aramid/epoxy are frequently used in aircraft and aerospace industries. These materials are prone to suffer from the presence of delamination, which can reduce severely the performance of aircrafts and even threaten their safety. Since electric conductivity of these composites is rather small, they can propagate electromagnetic waves. Detection of delamination damage can then be monitored by using an electromagnetic penetrating radar scanner, which consists of emitting waves having the form of short time pulses that are centered on a given work frequency. While propagating, these waves undergo partial reflection when running into an obstacle or a material discontinuity. Habitually, the radar is moved at constant speed along a straight path and the reflected signal is processed as a radargram that gives the reflected energy as function of the two-way time and the antenna position.In this work, modeling of electromagnetic wave propagation in composites made from E-glass/epoxy was performed analytically. The electromagnetic wave reflection from a delamination defect was analyzed as function of key intervening factors which include the defect extent and depth, as well as the work frequency. Various simulations were performed and the obtained results have enabled to correlate the reflection pattern image features to the actual delamination defect characteristics which can provide quantification of delamination.

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New Approach to the Theory of Circular Dichroism

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19981187 ◽

1998 ◽

Vol 63 (8) ◽

pp. 1187-1201 ◽

Cited By ~ 1

Author(s):

Jaroslav Zamastil ◽

Lubomír Skála ◽

Petr Pančoška ◽

Oldřich Bílek

Keyword(s):

Electromagnetic Wave ◽

Circular Dichroism ◽

Electromagnetic Waves ◽

Maxwell Equations ◽

Optically Active ◽

Semiclassical Approach ◽

New Approach ◽

Isotropic Media ◽

New Formula ◽

Circular Dichroïsm

Using the semiclassical approach for the description of the propagation of the electromagnetic waves in optically active isotropic media we derive a new formula for the circular dichroism parameter. The theory is based on the idea of the time damped electromagnetic wave interacting with the molecules of the sample. In this theory, the Lambert-Beer law need not be taken as an empirical law, however, it follows naturally from the requirement that the electromagnetic wave obeys the Maxwell equations.

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Preparation and electromagnetic properties characterization of reduced graphene oxide/strontium hexaferrite nanocomposites

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0010 ◽

2020 ◽

Vol 9 (1) ◽

pp. 105-114 ◽

Cited By ~ 1

Author(s):

Shumin Du ◽

Huaiyin Chen ◽

Ruoyu Hong

Keyword(s):

Electromagnetic Wave ◽

Environmental Pollution ◽

Electromagnetic Interference ◽

Electromagnetic Waves ◽

Rapid Development ◽

Living Environment ◽

World Health ◽

Electromagnetic Properties ◽

Strontium Hexaferrite ◽

Wave Radiation

AbstractWith the rapid development of electronics and information technology, electronics and electrical equipment have been widely used in our daily lives. The living environment is full of electromagnetic waves of various frequencies and energy. Electromagnetic wave radiation has evolved into a new type of environmental pollution that has been listed by the WHO (World Health Organization) as the fourth largest source of environmental pollution after water, atmosphere, and noise. Studies have shown that when electromagnetic wave radiation is too much, it can cause neurological disorders. And electromagnetic interference will cause the abnormal operation of medical equipment, precision instruments and other equipment, and therefore cause incalculable consequences. Therefore, electromagnetic protection has become a hot issue of concern to the social and scientific circles.

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Transmissive 2-bit anisotropic coding metasurface

Chinese Physics B ◽

10.1088/1674-1056/ac4a6b ◽

2022 ◽

Author(s):

Pengtao Lai ◽

Zenglin Li ◽

Wei Wang ◽

Jia Qu ◽

Liang Wei Wu ◽

...

Keyword(s):

Angular Momentum ◽

Electromagnetic Wave ◽

Circular Polarization ◽

Orbital Angular Momentum ◽

Electromagnetic Waves ◽

Beam Splitter ◽

Far Field ◽

Polarization Conversion ◽

Field Patterns ◽

Phase Profile

Abstract Coding metasurfaces have attracted tremendous interests due to unique capabilities of manipulating electromagnetic wave. However, archiving transmissive coding metasurface is still challenging. Here we propose a transmissive anisotropic coding metasurface that enables the independent control of two orthogonal polarizations. The polarization beam splitter and the OAM generator have been studied as typical applications of anisotropic 2-bit coding metasurface. The simulated far field patterns illustrate that the x and y polarized electromagnetic waves are deflected into two different directions, respectively. The anisotropic coding metasurface has been experimentally verified to realize an orbital angular momentum (OAM) beam with l = 2 of right-handed polarized wave, resulting from both contributions from linear-to-circular polarization conversion and the phase profile modulation. This work is beneficial to enrich the polarization manipulation field and develop transmissive coding metasurfaces.

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