NOVEL ELECTRIC FIELD EXPOSURE CONTROL METHODS FOR MULTI-STORY BUILDINGS INSTALLED IN VICINITY OF HIGH-VOLTAGE APPARATUS USING FEM

Facilities and buildings installed nearby high voltage equipment and electric field exposure is always a serious threat to the health of organisms and can have a significant impact on the functioning of sensitive and vital organs such as the heart and brain. Therefore, it is necessary to study the electromagnetic field value in these areas to control the intensity and restrict the induced value regarding to international recommendations. In this paper, the effects of 230KV transmission line electric fields on the environment are examined by proper FEM software.The model under consideration in this project is a four story building adjacent to the 230KV transmission line.At first, the distance between the building and high voltage transmission lines and its relationship to the intensity of the electric field is examined, and then the intensity of the electric field is compared to the standards of the International Commission on Non Ionizing Radiation Protection (ICNIRP). To continue, in places where the electric field exceeds the standard level value, solutions to reduce the intensity of the electric field to the tolerable value have been proposed.The first solution is to use a metal shield around the building as a Faraday cage, which weakens the potential for electric field value by creating an enclosed surface, the reduction rate is 4700%,both complete cage shape and incomplete cage shapes are considered in this study which reduces the exposure value to 62.5% of its initial value. The second approach to reducing the electric field is to use protective conductor paints against electromagnetic fields. In the following study, the effect of using trees as a barrier against electromagnetic radiation will be examined. Finally, the three proposed solutions are compared in terms of environmental constraints, economic justification, and the reduction in electric field value.

The effect of high-penetrating emission on the growth, superoxide accumulation and ATP/ADP ratio in Saccharomyces cerevisiae

Many kinds of physical field are able to affect the biological activity, such as electromagnetic field, magnetic field, scalar wave, magnetic vector potential and so on. Some works investigated a high-penetrating emission (HPE) generated by a LED generator that can affect the conductivity of water and the growth of dry yeast. In this research, the biological effect of the HPE of LED generator on S. cerevisiae was studied. The results showed that this kind of HPE could promote the growth of S. cerevisiae. With the decrease of initial concentration and the extension of exposure time, the growth promoting effect of HPE increased significantly. When the initial cell concentration was 2 × 102 cell/ml and exposed for 24 h, the number of yeast cells increased by 19.5% compared with the control group. Further studies showed that adenosine triphosphate (ATP) content and the ratio of ATP and adenosine diphosphate (ADP, ATP/ADP ratio) of exposed cells were higher than those of unexposed cells, indicating that exposed cells had higher cell viability and energy status. In addition, the intracellular superoxide (O2−) content decreased significantly after the HPE exposed. In this study, the stainless steel box acts as a Faraday cage to shield the electromagnetic field, so the biological effect of the HPE is not produced by the electromagnetic field. Nevertheless, the mechanism of the HPE is still unknown and needs further research. This is the first report on the effect of HPE on mitochondrial parameters, contributing to further study on HPE and revealing potential for future medical applications.

EXAMINATION OF ELECTRIFICATION OF OBJECTS FLYING THROUGH FIRE FUMES

Firstly, a special Faraday cage was used to measure the own electric charge for a model source of fire fumes. The spatial density of the charge, having the sign changing from place to place, does not exceed +/-3 nC/m3. Then, special duralumin projectiles were fired through the produced cloud of fumes with the mean velocity of ca. 150 m/s. The projectiles terminated the flight in a target, the electrode connected to an electrometer, which collected the electric charge accepted during the flight. The established density of the electrification current for projectiles was 30-400 mikro A/m2 what suggests that the charge was collected in the way of triboelectrification rather than by the interception of the fume’s own electric charge.

Phases of holographic interfaces

We compute the phase diagram of the simplest holographic bottom-up model of conformal interfaces. The model consists of a thin domain wall between three-dimensional Anti-de Sitter (AdS) vacua, anchored on a boundary circle. We distinguish five phases depending on the existence of a black hole, the intersection of its horizon with the wall, and the fate of inertial observers. We show that, like the Hawking-Page phase transition, the capture of the wall by the horizon is also a first order transition and comment on its field-theory interpretation. The static solutions of the domain-wall equations include gravitational avatars of the Faraday cage, black holes with negative specific heat, and an intriguing phenomenon of suspended vacuum bubbles corresponding to an exotic interface/anti-interface fusion. Part of our analysis overlaps with recent work by Simidzija and Van Raamsdonk but the interpretation is different.

Shielding Device for Microwave Electronic Components of a Multilayer Board for the AFAR Transceiver Module for Space Purposes

A method of shielding the elements of a microwave module based on the principles of forming a Faraday cage, with different power and different frequency paths of the AFAR receiving-transmitting module, excluding their mutual electromagnetic influence, is presented. A description of the structure of a multilayer board and various structural elements is given, allowing to limit (screen) the signal in a small volume, commensurate with the size of a monolithic integrated circuit or a set of monolithic integrated circuits, isolating parasitic electromagnetic interference. Polyimide is considered as a dielectric material of a multilayer microwave board for use in space technology devices, as well as promising design solutions for reducing the mass and dimensions of the module.