scholarly journals A Method For Determination Of Specific Electrical Resistance Of Steel And Nano-Coating Sputtered On It

2015 ◽  
Vol 2 ◽  
pp. 118 ◽  
Author(s):  
Andris Martinovs ◽  
Josef Timmerberg ◽  
Konstantins Savkovs ◽  
Aleksandrs Urbahs ◽  
Paul Beckmann
Keyword(s):  
Electrical Conductivity ◽  
Magnetic Permeability ◽  
Electrical Resistance ◽  
Skin Effect ◽  
Specific Electrical Resistance ◽  
Specific Electrical Conductivity ◽  
Relative Magnetic Permeability ◽  
Nano Coating ◽  
Cylindrical Steel

The paper describes methods developed to determine specific electrical conductivity and relative magnetic permeability of cylindrical steel items and nano-coatings deposited on them by sputtering. Research enables development of a new method for determination of thickness of vacuum deposited nano- coating that is based on application of skin effect.

scholarly journals БЕЗКОНТАКТНИЙ МЕТОД ТРИПАРАМЕТРОВОГО ВИМІРЮВАЛЬНОГО КОНТРОЛЮ ФІЗИКО-ХІМІЧНИХ ХАРАКТЕРИСТИК ЗРАЗКА ФЕРОМАГНІТНОЇ РІДИНИ

2018 ◽  
Vol 124 (4) ◽  
pp. 77-84
Author(s):  
В. В. Себко ◽  
В. Г. Здоренко
Keyword(s):  
Electrical Conductivity ◽  
Magnetic Permeability ◽  
Electromagnetic Method ◽  
Specific Electrical Conductivity ◽  
Parameter Method ◽  
Chemical Characteristics ◽  
Parameter Control ◽  
Relative Magnetic Permeability ◽  
Physical And Chemical ◽  
Measuring Control

The aim of the article is to investigate the method of three-parameter control of a sample of a ferromagnetic liquid, the realization of which is carried out on the basis of a noncontact transformer electromagnetic converter (TEC) with samples of ferromagnetic liquids in a longitudinal magnetic field.We used a technique for studying samples of a ferromagnetic liquid for the realization of a three-parameter electromagnetic method for measuring the physical and chemical characteristics of ferromagnetic liquids based on thermal TEC. The three-parameter method of measuring control of the relative magnetic permeability mr, the specific electrical conductivity σ, and the temperature t of a sample of a ferromagnetic liquid, which is monitored on the basis of measurements and analysis of signals of a thermal contactless three-parameter TEC, is studied. The theoretical principles of the operation of a contactless thermal TEC with a sample of a ferromagnetic liquid are based on the realization of a three-parameter method for measuring the monitoring of magnetic, electrical, and temperature parameters.

scholarly journals Electrical conductivity of whole and shredded plant tissue

2021 ◽  
Vol 264 ◽  
pp. 04072
Author(s):  
Nodir Eshpulatov ◽  
Tolib Khalmuradov ◽  
Rakhmаnberdi Khalilov ◽  
Abdulkhay Obidov ◽  
Madrakhim Allanazarov
Keyword(s):  
Electrical Conductivity ◽  
Experimental Study ◽  
Plant Tissue ◽  
Electrical Resistance ◽  
Specific Electrical Resistance ◽  
Specific Pressure ◽  
Pressing Time ◽  
Dial Indicator

The article gives the electrical conductivity of whole and shredded plant tissue. An experimental study was made of the dependence of the resistivity value and the volume occupied by the pulp on the pressing time and specific pressures on the pulp while taking into account the amount of pressed juice. The electrical resistance (R) of whole and crushed plant tissue was experimentally studied, which, when processing the results, was recalculated to the specific electrical resistance (ρ) of the tissue. The specific pressure (P) on the tissue was determined using a reference manometer, and the deformation (ΔH) of the sample was measured with a dial indicator.

Determination of the electrical conductivity of human liver metastases: impact on therapy planning in the radiofrequency ablation of liver tumors

2016 ◽  
Vol 58 (2) ◽  
pp. 164-169 ◽  
Author(s):  
Urte Zurbuchen ◽  
Franz Poch ◽  
Ole Gemeinhardt ◽  
Martin E Kreis ◽  
Stefan M Niehues ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Radiofrequency Ablation ◽  
Liver Metastasis ◽  
Liver Metastases ◽  
Liver Tissue ◽  
Colorectal Liver Metastases ◽  
Liver Tumors ◽  
Tissue Temperature ◽  
Specific Electrical Conductivity

Background Radiofrequency ablation is used to induce thermal necrosis in the treatment of liver metastases. The specific electrical conductivity of a liver metastasis has a distinct influence on the heat formation and resulting tumor ablation within the tissue. Purpose To examine the electrical conductivity σ of human colorectal liver metastases and of tumor-free liver tissue in surgical specimens. Material and Methods Surgical specimens from patients with resectable colorectal liver metastases were used for measurements (size of metastases <30 mm). A four-needle measuring probe was used to determine the electrical conductivity σ of human colorectal liver metastasis (n = 8) and tumor-free liver tissue (n = 5) in a total of five patients. All measurements were performed at 470 kHz, which is the relevant frequency for radiofrequency ablation. The tissue temperature was also measured. Hepatic resections were performed in accordance with common surgical standards. Measurements were performed in the operating theater immediately after resection. Results The median electrical conductivity σ was 0.57 S/m in human colorectal liver metastases at a median temperature of 35.1℃ and 0.35 S/m in tumor-free liver tissue at a median temperature of 34.9℃. The electrical conductivity was significantly higher in tumor tissue than in tumor-free liver tissue ( P = 0.005). There were no differences in tissue temperature between the two groups ( P = 0.883). Conclusion The electrical conductivity is significantly higher in human colorectal liver metastases than in tumor-free liver tissue at a frequency of 470 kHz.

Carbon reinforced concrete and temperature

2019 ◽  
Author(s):  
Frank Schladitz ◽  
Emanuel Lägel ◽  
Daniel Ehlig
Keyword(s):  
Electrical Conductivity ◽  
Reinforced Concrete ◽  
Electrical Resistance ◽  
Manufacturing Process ◽  
Fresh Concrete ◽  
Building Construction ◽  
Specific Electrical Resistance ◽  
Temperature Stresses ◽  
Different Temperatures ◽  
Construction Practice

<p>Carbon reinforced concrete — a combination of non-corroding carbon reinforcement and concrete — has been investigated for over 20 years and has been used extensively in construction practice for more than 10 years for new constructions and for renovation. Wall and ceiling constructions in building construction as well as bridges and platform systems were newly erected, but also roofs, silos and bridges were renovated. During its manufacturing process but also during its time of use, carbon reinforced concrete can be affected by temperature stresses. The paper starts with an overview of how the temperature characteristics at different temperatures are to be evaluated. Furthermore, it will be shown how mat-like carbon reinforcement with its electrical conductivity and the high specific electrical resistance of approx. 16 Ω-mm²/m can be used for the deliberate heating of carbon concrete components. In addition, carbon reinforcement can be used to achieve thermal prestressing of fresh concrete components similar to prestressed glass panes.</p>

scholarly journals Application of independent-channel method for investigation of electrical conductivity of graphene-containing shungite.

2021 ◽  
Author(s):  
I.V. Antonets ◽  
◽  
E.A. Golubev ◽  
V.G. Shavrob ◽  
V.I. Shcheglov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Spatial Distribution ◽  
Current Flow ◽  
Specific Conductivity ◽  
Specific Electrical Conductivity ◽  
Parallel Connection ◽  
Raster Electron Microscopy ◽  
Current Flows

The independent channel method which is intended for the calculation of specific electrical conductivity of graphene-contained shungite is proposed and realized on practice. It is noted that the most important of shungite application is the creation of screen hawing large area which are able to block electromagnetic radiation in wide frequency range. The most important factor which determines the blocking properties of shungite is the specific electrical conductivity of its carbon part which is determined by the spatial distribution of carbon atoms. As a main method of carbon structure investigation is mentioned the high-resolution raster electron microscopy which allows from the surface of specimen to receive the card of distribution of graphene slides and graphene packets. The spatial factor which determines the shungite conductivity is large anisotropy of single graphene slide which reaches three orders and more in the cases along and across the slide. The proposed method independent channels takes into consideration the arbitrary orientation of graphene packets relatively to direction of current flow. As a basis of method is employing the card of carbon spatial distribution which is received by raster electron microscopy method. The card is divided by parallel channels which transverse dimension is near or slightly exceeds the typical dimension of graphene packet. The channels are divided to square blocks which sides are equal to width of channel. The whole resistance of channel is formed by the successive connection of individual resistances of blocks. The resistance of whole card is determined by parallel connection of channels or averaging of resistance of all channels and following filling the whole area of card. The first step of analysis is the determination of advantage orientation of slides inside of every blocks. On the basis of determined orientation the block is filled by periodic structure which period is equal to the width of graphene slide and neighbouring interval. As a parameter which determines the orientation is used the angle between advantage orientation of graphene slides and axis of current flow between contacts. Owing to symmetry of task in comparison of current direction the limited meanings of corner is 0 and 90 degree. It is established two principal different cases of orientation: first – when determining angle is less than 45 degree and second when this angle is more than 45 degree. In the first case the current flows along the stripe with large conductivity. In the second case the current flows across these stripes so as through the stripes with low conductivity. It is found the smooth dependence of block resistivity from the angle of strip orientation. For the characteristic of area which is filled graphene slides it is proposed the coefficient of filling which is determined by binary discretization method. On the basis of analysis of slides orientation and filling coefficients are calculated the resistance of individual blocks. The resistances of all channels of investigated card are proposed. By using two methods – parallel connection and averaging over all channels it is calculated the specific electrical resistance and specific electrical conductivity of material as a whole. It is found that the received values of specific conductivity exceed the determined in experiment value in several (to 10) times. For the coordination of calculated value with experimental value it is made the variation of specific resistances of graphene slides and intervals between its. It id found that the calculation by method of parallel connection of channels ensures several better coordination than method of averaging. It is shown that the resistance is improved in the first turn by the increasing the resistance of interval between slides. In the quality of possible reason of decisive role of interval it is proposed the observed in experiment sharp non-homogeneity of relative arrangement of graphene slides. It is discussed the possible courses of further development of work. As a most important task it is proposed the more circumstantial determination of statistical character of received results.

Sign in / Sign up

Export Citation Format

Share Document