An Interaction Between Electromagnetic Fields And Bio-system And Security Analysis

The application of electromagnetic field and electromagnetic wave in medicine and biology become more and more extensive with the quick development of electronics technology, which greatly improve the quality of life and health, at the same time, the electromagnetic radiation has become a new environment pollution source which maybe endanger human health. The three areas of basic research as support to whether the further development and use of electromagnetic wave or the assessment and protection of it's negative effects: the first is the experiment study on the biological effects of electromagnetic waves which answer the question of what application, the second is mechanism which answer the question of what is the theoretical basis for the application; the third is biological electromagnetic dosimetry study, which answer the application could be used under what kind of the electromagnetic action. The features of the three areas in this paper is the characteristic quality in time-frequency domain as indicators which be used in the study on biological window effects; the geometry parameters and charge distribution parameters of membrane ion channels be used to calculate the potential distribution and the electric field distribution along with axial in ion channels in mechanism study, the results show that the physical basis of the window effects is periodic distribution of potential barrier, the periodic electric field distribution and the convergence of electromagnetic energy caused by nonlinear polarization characteristics in membrane, which give the enough energy basis for ion to cross the barrier; The evaluation of electromagnetic dosimetry from the point of view of the auditory effects and the effects of temperature rise is performed by the extension from the study of absorbed power to the study of electric field stress and temperature rise in biological electromagnetic dosimetry study.?. The study on biological window effects of ELF electromagnetic waveThe Ca ²⁺ is study object which is usually used in window effect, based on the measurement method of calcium ion concentration in cell and the system of biological experimental irradiation on ELF electromagnetic wave, the system was designed and manufactured by ourselves. The brain issue of chicken and the liver cancer cells of human being (7721) were investigated respectively with the method of isotope tracing and fluorescent mark. the ELF electromagnetic wave with different properties as a factor, the radioactivity intensity and fluorescence intensity, which express the concentrations of Ca ²⁺ ,were measured with the liquid scintillation counter and laser scanning confocal microscope, a typical case of the athermal bio-effects of electromagnetic wave,that is,the window bio-effects of ELF electromagnetic wave,was studied. In the study we focus on the response of the concentrations of Ca ²⁺ in cell to electromagnetic wave in time-frequency domain which extend the traditional study that biological effect of electromagnetic wave in time domain to time-frequency domain, which can obtain further information. The results of experiment show that there exist frequency-window and intensity-window effects of electromagnetic wave whether in time domain or in time-frequency domain, and also show that the window bio-effects would be occurred under the condition of the right combination of frequency and intensity of electromagnetic wave, the results of time-frequency analysis show that the bio-effects of the concentrations of Ca ²⁺ in cell would be occurred under the action of certain frequency and intensity of ELF electromagnetic wave which shows the width of continuous spectrum, the number of discrete spectrum and the center frequency of discrete spectrum are changed. The comprehensive analysis of a series of electromagnetic parameters which can produce or not produce bio-effects was performed that show there also exists window bio-effects in time-frequency domain. In addition, in order to explore the physical basis of electromagnetic waves action, the characteristics of the Ca ²⁺ concentration of 7 kinds of cell was studied in time-frequency domain on physiological conditions that there is not electromagnetic wave action, the results show that there exist similarities and difference among the different cells, the similarities are that there exist both discrete spectrum and continuous spectrum, the biological effect is or is not produced is exactly reflected in whether the characteristics of the two spectral change, the differences are that the bandwidth of continuous spectrum and the center frequency of discrete spectrum are different. Those differences can give a new kind of idea for cancer cell detection and the evaluation of health status of normal cells.?. Mechanism analysis of the window effectBased on the closely relationship between the Ca ²⁺ concentration change and the volume of Ca ²⁺ through the ion channels which constructed by?–helix protein molecules in cell membrane, we calculated the potential distribution and the electric field distribution along with channel axis through the geometry parameters and charge distribution parameters of?–helix protein molecules, the results show that there exist the periodic potential barrier distribution and the periodic potential distribution along channel axis. The height of the barrier is basic energy unit that is required for ion movement in the channel, if making the ion across n-barrier, then the energy provided to the ion by electromagnetic wave must be n-times of the basic unit, which means that the intensity of electromagnetic wave is a series of discrete values for the ion movement in channel, which is basic of mechanism of intensity window effects. At the same time, the ion cross a barrier need some time, which is basic time unit, if making the ion across n-barrier, the time spent by the ion must be n-times of the basic time unit, which means that if the ion moves along forward in channel, then the time maintained by the positive direction electromagnetic field should be n-times of the basic time, then the half cycle of electromagnetic wave is required to be n-times of the basic time. So we can see that the cycle of electromagnetic wave is required to be a series of discrete values if the ion movement forward in channel in accord with the cycle. Because of the certain relationship between frequency and cycle, so the frequency of electromagnetic wave is required to be a series of discrete value which is basic of mechanism of frequency window effects. In fact, only the energy provided to the ion is n-times of the basic energy unit and the time maintained by positive electric wave is also happens to n-times of the basic time unit that can make the ion across n-barrier. In addition, the estimated value suggest that the energy of the radiation electromagnetic wave can not make the ion across the barrier, so we put forward the views of local convergence of electromagnetic wave energy, the basic idea is the polarization of the medium exhibit obvious nonlinear polarization characteristics for there is 10⁷V/m electric field in membrane and there also exist the periodic electric field distribution along with channel axis, therefore the dielectric constant of the two sides of the channel cross-section is not the same which make electromagnetic wave reflected on the interface, the results of reflection form a standing wave which means there exist the energy convergence of electromagnetic wave near wave loop, the ions in this region would be obtain larger energy than irradiation wave that can make ion across the barrier. In summary, we not only gave the physical basis of intensity window effects and frequency window effects but also showed the correlation between them. The results of energy convergence can give a reasonable explanation on the biological effects of low-intensity electromagnetic wave.?.The electric field stress, temperature rise in human head caused by mobile phone radiation and safety evaluationFor the consideration of electromagnetic wave will generate electric field stress in discontinuous medium, we calculated the electric field stress distribution in human head caused by mobile phone radiation and the safety evaluation of mobile phone radiation was performed from the angle that the electric field stress whether reach to the threshold of auditory effects and produce auditory effects further. For the consideration of the temperature rise of biological tissues caused by electromagnetic irradiation and the brain is most sensitive to temperature rise, based on the power distribution in human head caused by mobile phone and heat transfer characteristics of biological tissues,we analyzed and calculated the temperature distribution inside the skull, gave the temperature area and temperature value under the radiation power of current mobile phone. For the consideration of the impact of human head on mobile phone antenna radiation when handsets are designed, we calculated the effect of human head on mobile antenna radiation characteristics, we not only gave the two-dimensional pattern but also some typical data, in addition, the effect of human head on mobile phone input impedance was also studied which can be used to evaluate the impact of human head on the antenna radiation efficiency. Measures which can reduce radiation power absorbed by human head were also put forward.