scholarly journals Design of liquid composite materials for shielding electromagnetic fields

2021 ◽  
Vol 3 (6 (111)) ◽  
pp. 25-31
Author(s):  
Valentyn Glyva ◽  
Volodymyr Bakharev ◽  
Natalia Kasatkina ◽  
Oleg Levchenko ◽  
Larysa Levchenko ◽  
...  
Keyword(s):  
Electromagnetic Field ◽  
Composite Materials ◽  
Electromagnetic Fields ◽  
Electromagnetic Waves ◽  
Iron Ore ◽  
Dielectric Permeability ◽  
Wide Frequency Range ◽  
Protective Properties ◽  
Principles Of Design ◽  
Iron Ore Concentrate

This paper reports the principles of design and the examined protective properties of liquid materials for shielding the electric, magnetic, and electromagnetic fields over a wide frequency range. The materials were made on the basis of iron ore concentrate and a pigment additive, with water-dispersed and geopolymer paints used as a matrix. The tests of protective properties for the electrical and magnetic components of the electromagnetic field of industrial frequency showed that the electric field shielding coefficients at a concentration of the screening substance of 15−60 % (by weight) equaled 1.1−8.6; magnetic field – 1.2−5.3. The shielding coefficients of the material based on a water-dispersed paint are lower than those of a geopolymer one, which can be explained by the oxidation of an iron-containing component and a decrease in electrical conductivity. The shielding coefficients of the electromagnetic field with a frequency of 2.45 GHz are 1.2−7.9. The highest coefficients are inherent in the material with filler made of iron ore concentrate and titanium-containing pigment powder in a ratio of 1:1. To design materials with the required (predictable) protective properties, the relative magnetic, dielectric permeability of materials was calculated. It is shown that the obtained data are acceptably the same as the results from direct measurements of magnetic and dielectric permeability and could be used to calculate the wave resistance of the material and the predicted reflection coefficient of electromagnetic waves. Thus, there is reason to assert the need to build a database on the frequency dependence of effective magnetic and dielectric permeability in order to automate the design processes of composite materials with predefined protective properties.

scholarly journals SUBSTANTIATION OF APPLICATION FEATURES OF LIQUID MIXTURES FOR SCREENING OF ELECTROMAGNETIC FIELDS

2021 ◽  
Vol 3 (163) ◽  
pp. 239-243
Author(s):  
O. Tykhenko
Keyword(s):  
Electromagnetic Field ◽  
Composite Materials ◽  
Rheological Properties ◽  
Electromagnetic Fields ◽  
Iron Ore ◽  
Liquid Mixtures ◽  
Ultrahigh Frequency ◽  
Filler Concentration ◽  
Iron Ore Concentrate ◽  
Industrial Frequency

The protective and rheological properties of composite materials based on water-dispersed paint and iron ore concentrate were studied. Features of liquid mixtures application for shielding of magnetic field of industrial frequency and electromagnetic field of ultrahigh frequency were substantiated. The study of the protective characteristics and rheological properties of composite materials based on water-dispersed paint and iron ore concentrate indicates the possibility of their use for shielding electromagnetic fields of a wide frequency range. It was found that the efficiency of the composite material (total shielding coefficient and reflection coefficient of electromagnetic waves) depends on the dispersion of the shielding filler, so the particle size analysis of iron ore concentrate was performed. The analysis shows that the predominant size of iron-containing particles is 23‒24 μm, which is quite acceptable for their uniform distribution in the body of the matrix. Shielding protective material was made of water-dispersion paint with the addition of iron ore concentrate in weight quantities of 15, 30, 45, 60%. The shielding coefficients of the electromagnetic field of industrial frequency and ultrahigh frequency with different filler content were measured. It was found that if the concentration of filler exceeds 30%, both the rheological characteristics of the mixture and the shielding coefficients of electromagnetic fields are unsatisfactory. A dramatic increase in shielding coefficients occurs at a filler concentration of 40%. This mixture has acceptable adhesive properties. It was established that the shielding coefficients could be enhanced if the dispersion of the filler is increased, which will contribute to the stability of the colloidal mixture and improve the rheological properties.

scholarly journals Development and study of protective properties of the composite materials for shielding the electromagnetic fields of a wide frequency range

2020 ◽  
Vol 2 (12 (104)) ◽  
pp. 40-47
Author(s):  
Valentyn Glyva ◽  
Natalia Kasatkina ◽  
Vasyl Nazarenko ◽  
Nataiia Burdeina ◽  
Nataliia Karaieva ◽  
...  
Keyword(s):  
Composite Materials ◽  
Electromagnetic Fields ◽  
Wide Frequency Range ◽  
Frequency Range ◽  
Protective Properties

scholarly journals Using the Carotazh Method to Determine the Electrical Characteristics of the Earth’s Subsoil

2021 ◽  
Keyword(s):  
Magnetic Field ◽  
Electrical Conductivity ◽  
Electromagnetic Field ◽  
Surface Impedance ◽  
Electromagnetic Waves ◽  
Dielectric Permeability ◽  
Electrical Characteristics ◽  
Measuring Systems ◽  
The Earth ◽  
The Magnetic Field

Logging is a detailed study of the structure of the well incision by descent and ascent of a geophysical probe. It is often used to determine the electrical conductivity of terrestrial depths. To do this, the sides of the well deepen the electrodes, and they are fed into the depths of a constant electric current. However, if you use natural or artificial electromagnetic waves, it becomes possible to determine the dielectric permeability of terrestrial rocks at depth. To do this, the surface impedance is first measured on the surface of the earth, and then by measuring at a certain frequency of the electromagnetic field in the well hole, the electrical conductivity and dielectric permeability of terrestrial rocks are calculated by fairly simple formulas. Such measurements can be carried out by standard measuring systems, adding only a narrow frame with wire winding to measure the magnetic field.

scholarly journals Selection of Non-Magnetic Fraction from the Slime Wastes of Metal Production in the Electromagnetic Field

2019 ◽  
Vol 297 ◽  
pp. 04002 ◽  
Author(s):  
Yuri Vernigorov ◽  
Valery Lebedev ◽  
Lidianna Chunakhova
Keyword(s):  
Electromagnetic Field ◽  
Iron Ore ◽  
Inhomogeneous Magnetic Field ◽  
Silica Content ◽  
Magnetic Fraction ◽  
Metal Production ◽  
Effective Technology ◽  
Maximum Development ◽  
Iron Ore Concentrate ◽  
Selection Of

It is proved that the use of a variable inhomogeneous magnetic field, created by the superposition of constant and variable, strongly inhomogeneous fields, is considered to be very promising for the separation of non-magnetic fraction from powders of magnetic materials. This article introduces the effective technology of separation of non-magnetic fraction from the sludge wastes of metal production in the electromagnetic field, which allows to destroy the aggregates, to separate the abrasive and to get products of high purity. A complex on processing of grinding sludge includes the following blocks: the loading block with dispenser; block of preliminary squeezing and washing of DRC; the block of drying; the block of a refinement; the block of division of sludge fractions. Experimental approbation of the proposed technological scheme of sludge separation, which had been carried out on iron ore concentrate of class 63 microns with silica content of 4.57% of the mass, showed that with the field parameters close to the calculated, the magnetic vibrating layer of iron powder PZh-4M has the maximum development; increasing the separation time leads to more efficient separation in the interval of field induction gradient from 550 mT/ m to 610 mT/m.

Levels of Electromagnetic Fields From Rail Vehicles in the Context of Formal Requirements

2020 ◽  
Vol 64 (187) ◽  
pp. 109-116
Author(s):  
Andrzej Miszkiewicz ◽  
Krzysztof Tchórzewski
Keyword(s):  
Electromagnetic Field ◽  
Electromagnetic Fields ◽  
Electromagnetic Waves ◽  
Electronic Systems ◽  
Civil Protection ◽  
Rail Vehicles ◽  
Railway Industry ◽  
Measurement Results ◽  
Formal Requirements ◽  
Initial Results

The article discusses the issue of electromagnetic field levels emitted from rail vehicles with regard to civil protection. The article presents the lack of legal solutions, limits and research methods in the railway industry in Poland. It also depicts the initial results of measurements from rail vehicles. Based on the findings, taking into consideration the measurement results and suppression of electromagnetic waves in free space, electromagnetic fields may reach substantial levels which can affect people’s health and life. The authors of the article conclude that the problem should not be ignored and requires further research, bearing in mind the progressing saturation of all rail vehicles with devices and electronic systems which will serve as sources of electromagnetic fields. Keywords: electromagnetic fields, civil protection, measurements

CLEANING UP EMERGENCY OIL SPILLS FROM THE WATER SURFACE WITH MAGNETIC ADSORBENTS

2017 ◽  
Author(s):  
Yury Rubanov ◽  
Yury Rubanov ◽  
Yulia Tokach ◽  
Yulia Tokach ◽  
Marina Vasilenko ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Water Surface ◽  
Iron Ore ◽  
Oil Spills ◽  
Air Cooling ◽  
Steelmaking Slag ◽  
Magnetic Adsorbents ◽  
Ratio Of Components ◽  
Iron Ore Concentrate ◽  
Electric Furnace Steelmaking

There was suggested a method of obtaining a complex adsorbent with magnetic properties for the oil spill clean-up from the water surface by means of controlled magnetic field. As magnetic filler a finely-dispersed iron-ore concentrate in the form of magnetite, obtained by wet magnetic separation of crushed iron ore, was suggested. As an adsorbing component the disintegrating electric-furnace steelmaking slag, obtained by dry air-cooling method, was selected. The mass ratio of components slag:magnetite is 1(1,5÷2,0). For cleaning up emergency oil spills with the suggested magnetic adsorbent a facility, which is installed on a twin-hulled oil recovery vessel, was designed. The vessel contains a rectangular case between the vessel hulls with inlet and outlet for the treated water, the bottom of which is a permanently moving belt. Above the belt, at the end point of it there is an oil-gathering drum with magnetic system. The adsorbent is poured to oil-products layer from a hopper, provided with drum feeder. Due to the increased bulk weight the adsorbent sinks rapidly into the oil layer on the water surface. If the large non-floating flocculi are formed, they sink and sedimentate on the moving belt and are moved to the oil-gathering drum. The saturated adsorbent is removed from the drum surface with a scraper, connected with a gutter, with contains a rotating auger.

Mechanism on reduction swelling of pellets prepared from Bayan Obo iron ore concentrate

2021 ◽  
pp. 1-11
Author(s):  
Yingjie Fan ◽  
Yunhao Zhang ◽  
Zhichao Li ◽  
Yifan Chai ◽  
Yici Wang ◽  
...  
Keyword(s):  
Iron Ore ◽  
Reduction Swelling ◽  
Bayan Obo ◽  
Iron Ore Concentrate

STRUCTURING OF CURED POLYMERIC COMPOSITE MATERIALS IN A MICROWAVE ELECTROMAGNETIC FIELD

2021 ◽  
pp. 3-9
Author(s):  
I. V. Zlobina
Keyword(s):  
Electromagnetic Field ◽  
Composite Materials ◽  
Polymer Composite ◽  
Contact Interaction ◽  
Energy Systems ◽  
Polymeric Composite ◽  
Strength Characteristics ◽  
Polymer Composite Materials ◽  
Reinforcing Fibers ◽  
The Matrix

Based on studies of the microstructure of the matrix of cured polymer composite materials and the area of its contact interaction with reinforcing fibers, the hypothesis of its structuring in the microwave electromagnetic field with an increase in the contact interaction surfaces due to an increase in the number of agglomerates with small transverse dimensions and a decrease in porosity in the macro- and mesopore regions is substantiated. These effects can be used as a basis for increasing the strength characteristics and uniformity of their values after exposure to a microwave electromagnetic field. The results of this work can be used in the development of technologies for finishing hardening of products made of carbon and fiberglass for various transport and energy systems.

Sign in / Sign up

Export Citation Format

Share Document