ON THE PROPAGATION OF E.L.F. PULSES IN THE EARTH–IONOSPHERE WAVE GUIDE

1962 ◽  
Vol 40 (10) ◽  
pp. 1360-1369 ◽  
Author(s):  
James R. Wait
Keyword(s):  
Spectral Analysis ◽  
Frequency Dependence ◽  
Time Domain ◽  
Propagation Constant ◽  
Low Frequency ◽  
Wave Guide ◽  
Transient Responses ◽  
Extremely Low Frequency ◽  
The Earth ◽  
Wave Forms

The paper is concerned with the connection between frequency domain and time domain for propagation in the earth–ionosphere wave guide. Attention is focussed on the extremely low frequency (e.l.f.) range. It is assumed that the propagation constant is proportional to (frequency)v where v is a fraction between 0 and 1. For such a frequency law, the corresponding transient responses are computed. These illustrate a number of important points. In particular, it is indicated that the frequency dependence of the propagation constant could be estimated directly from the wave forms themselves without resorting to conventional spectral analysis.

Psychophysiological Effects of Extremely Low Frequency Electromagnetic Fields: A Review

1973 ◽  
Vol 36 (3_suppl) ◽  
pp. 1131-1159 ◽  
Author(s):  
M. A. Persinger ◽  
H. W. Ludwig ◽  
K-P. Ossenkopp
Keyword(s):  
Experimental Data ◽  
Low Frequency ◽  
Geomagnetic Disturbances ◽  
Extremely Low Frequency ◽  
Magnetic Components ◽  
Wave Forms ◽  
Electrical Component ◽  
Power Densities ◽  
Cardiovascular Functions ◽  
Electrical Appliance

Extremely low frequency (ELF) electromagnetic field-waves, defined in this paper as occupying the frequency band of .01 to 100 Hz, are associated with geomagnetic disturbances, weather perturbations, electrical appliance discharges, and possibly seismic movements. ELF electromagnetic phenomena have been recorded as sinusoidal-like wave forms or as ELF pulses of short duration from higher frequency (10 to 100 kHz) waves. Although natural ELF electrical component intensities range from less than 1 mV/m to slightly more than 1 V/m with magnetic components less than a μ gauss and calculated power densities of 10−8 watts/m3, these waves can propagate long distances without appreciable attenuation and penetrate housing structures. Theoretically, it has been calculated that energy available from ELF phenomena can contribute to neuroenergetic functioning and protein-lipid activity. Correlational and experimental data indicate that ELF fields can influence reaction time, timing behavior, ambulatory behavior, oxygen uptake, endocrine changes, cardiovascular functions, and precipitation-clotting times of colloids. Possible mechanisms of ELF-organismic interactions are discussed.

scholarly journals Electromagnetic Fields Effects on the Secondary Structure of Lysozyme and Bioprotective Effectiveness of Trehalose

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Emanuele Calabrò ◽  
Salvatore Magazù
Keyword(s):  
Electromagnetic Field ◽  
Spectral Analysis ◽  
Secondary Structure ◽  
Mobile Phone ◽  
Ftir Spectroscopy ◽  
Electromagnetic Fields ◽  
Low Frequency ◽  
Ftir Spectra ◽  
Vibration Band ◽  
Extremely Low Frequency

FTIR spectroscopy was used to investigate the effects of extremely low frequency (50 Hz) electromagnetic field and of microwaves at 900 MHz on the secondary structure of a typical protein, the lysozyme, evaluating the bioprotective effectiveness of trehalose. Lysozyme in D2O solution (60 mg/ml) was exposed to 50 Hz frequency electromagnetic field at 180 μT. The FTIR spectra indicated an increase of CH2 group at 1921 and 1853 cm−1 after 3 h of exposure. Such effect was not observed after the addition of trehalose (150 mg/mL) at the same exposure conditions. Lysozyme dissolved in D2O at the concentration of 100 mg/mL was exposed up to 4 h to 900 MHz mobile phone microwaves at 25 mA/m. A significant increase in intensity of the amide I vibration band in the secondary structure of the protein was observed after 4 h exposure to microwaves. This effect was inhibited by the presence of trehalose at the concentration of 150 mg/mL. Fourier self-deconvolution spectral analysis of lysozyme in D2O solution after exposure to microwaves revealed an increase in intensity of the conformational components of amide I mode, particularly of β-sheet and turn that can be attributed to disorder and unfolding processes of the protein.

Spectral analysis to assess exposure to extremely low frequency magnetic fields in cars

2017 ◽  
Vol 584-585 ◽  
pp. 875-881
Author(s):  
Jesús M. Paniagua ◽  
Montaña Rufo ◽  
Antonio Jiménez ◽  
Alicia Antolín ◽  
Jorge Barberá
Keyword(s):  
Spectral Analysis ◽  
Magnetic Fields ◽  
Low Frequency ◽  
Extremely Low Frequency

scholarly journals Simulation and Measurement of Through-the-Earth, Extremely Low-Frequency Signals Using Copper-Clad Steel Ground Rods

2017 ◽  
Vol 53 (5) ◽  
pp. 5088-5095
Author(s):  
Nicholas William Damiano ◽  
Lincan Yan ◽  
Bruce Whisner ◽  
Chenming Zhou
Keyword(s):  
Low Frequency ◽  
Extremely Low Frequency ◽  
The Earth ◽  
Clad Steel

scholarly journals Extremely low frequency electromagnetic field generator suitable for plant in vitro studies

2017 ◽  
Vol 63 (No. 4) ◽  
pp. 180-186
Author(s):  
Prihatini Riry ◽  
Abdullah Mohamad Puad ◽  
Abdullah Tuan Abdul Rashid bin Tuan ◽  
Said Ismail ◽  
Hussin Halil ◽  
...  
Keyword(s):  
Electromagnetic Field ◽  
Chlorophyll Content ◽  
Low Frequency ◽  
Culture Studies ◽  
Shoot Height ◽  
Extremely Low Frequency ◽  
Total Chlorophyll Content ◽  
The Earth ◽  
In Vitro Plantlets

The extremely low frequency electromagnetic field (ELF-EMF) occurs naturally from the earth and artificially as a human invention. The objectives of this study were to develop a suitable ELF-EMF generator for in vitro plants culture studies and to determine the effect of ELF-EMF exposure on in vitro tobacco (Nicotiana tabacum) growth and chlorophyll content. An ELF-EMF generator, the coGEM 1,000 was constructed using four coils of copper wires that were connected to a transformer, multimeter and rheostat. The coGEM 1,000 suitable for tissue culture plants is able to produce stable and uniform 6 and 12 mT 50Hz ELF-EMF in the four coils of the ELF-EMF generator. The tobacco in vitro plantlets were exposed to 6 and 12 mT of 50 Hz ELF-EMF for a period of 0.5, 1, 2 and 4 hours. The exposure to 12 mT ELF-EMF for an hour increased plant growth (shoot height); whereas the exposure to 6 mT Elf-EMF for an hour increased chlorophyll a, chlorophyll b and the total chlorophyll content.  

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