scholarly journals Influence Of Nanoparticles Diameter On Structural Properties Of Magnetic Fluid In Magnetic Field

2015 ◽  
Vol 66 (4) ◽  
pp. 231-234 ◽  
Author(s):  
Jozef Kúdelčík ◽  
Peter Bury ◽  
Štefan Hardoň ◽  
Peter Kopčanský ◽  
Milan Timko
Keyword(s):  
Magnetic Field ◽  
Structural Changes ◽  
Magnetic Fluids ◽  
Continuous Change ◽  
Acoustic Attenuation ◽  
Nanoparticle Diameter ◽  
Carrier Liquid ◽  
Basic Parameters ◽  
Transformer Oils ◽  
The Impact

AbstractThe properties of magnetic fluids depend on the nanoparticle diameter, their concentration and the carrier liquid. The structural changes in magnetic fluids with different nanoparticle diameter based on transformer oils TECHNOL and MOGUL under the effect of a magnetic field and temperature were studied by acoustic spectroscopy. At a linear and jump changes of the magnetic field at various temperatures a continuous change was observed of acoustic attenuation caused by aggregation of the magnetic nanoparticles to structures. From the anisotropy of acoustic attenuation and using the Taketomi theory the basic parameters of the structures are calculated and the impact of nanoparticle diameters on the size of structures is confirmed.

scholarly journals The Role of Modification of the Structure of Water and Water-Containing Systems in Changing Their Biological, Therapeutic, and Other Properties Overview

Water ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2441
Author(s):  
Galina Sidorenko ◽  
Mitja Brilly ◽  
Boris Laptev ◽  
Nikolay Gorlenko ◽  
Leonid Antoshkin ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Mineral Water ◽  
Structural Changes ◽  
Water Clusters ◽  
Force Microscopy ◽  
Structure Of Water ◽  
Atomic Force ◽  
The Impact ◽  
Non Destructive

Based on published research on modifying the structure of water and water-containing systems, we assess external influence methods: temperature, magnetic field, light radiation, and their combination. We evaluate changes in the electrophysical, photo- and pH-metric biological, therapeutic, and other properties of water systems using non-destructive electrophysical research methods, i.e., thermometry, pH, laser interference, dynamic light scattering, microelectrophoresis, conductivity, surface tension, dielectric constant, polarimetric measurements, atomic force microscopy, and UV and EPR spectroscopy. The effects of temperature or magnetic field lead to a change in the content and size of water clusters, and physicochemical, biological, therapeutic, and other changes in the properties of water and water-containing systems. The combined effect of a magnetic field and curative mud and the impact of magnetised mineral water have a more pronounced therapeutic effect than only mineral water or curative mud. The data presented indirectly indicate structural changes in water and water-containing systems. We conclude that the primary mechanism of action of a magnetic field, light, or a combination of these factors on water and water-containing systems, including mineral water and therapeutic mud, is a change in the structure of water.

Investigation on Magnetoviscous Effects of Water-Based Magnetic Fluid

2018 ◽  
Vol 281 ◽  
pp. 906-911
Author(s):  
Zhi Li Zhang ◽  
Nan Nan Di ◽  
Le Bai ◽  
Yang Yang ◽  
De Cai Li
Keyword(s):  
Magnetic Field ◽  
Magnetic Fluid ◽  
Magnetic Fluids ◽  
Magnetic Nanomaterials ◽  
Precipitation Method ◽  
Two Phase ◽  
Field Function ◽  
Carrier Liquid ◽  
Water Based ◽  
Co Precipitation

Magnetic fluid or called ferro-fluid is such kind of magnetic nanomaterials, which is stable of solid-liquid two phase colloidal solution composited by magnetic nanoparticles coated by surfactant and highly disperse in a carrier liquid. The basis of magnetic fluid widely applied mainly is due to their unique magnetic properties and rheological properties, which enable its action as intelligent control materials in the magnetic field so as to achieve the goal of magnetic liquid dynamic seal, magnetic damping vibration and so on. In our recent research, the water-based magnetic fluid was synthesized using a co-precipitation method and its magnetorheological properties were studied. During the process, the magnetorheological properties of stable water-based magnetic fluids were determined by magnetic rheometer. The results show that the shear-thinning behavior of magnetic fluids was observed both in the absence and presence of magnetic field. However, there was a remarkable magnetoviscous effect with magnetic field function and the unexpected variation of shear stress was related to the chain aggregation. Furthermore, the constitutive equation of water-based magnetic fluid at a low magnetic field was discussed.

scholarly journals Comparison of the Change of Acoustic Attenuation and Anisotropy in Magnetic Fluids Based on Transformer Oils

2020 ◽  
Vol 137 (5) ◽  
pp. 936-938
Author(s):  
J. Kúdelčík ◽  
Š. Hardoň ◽  
P. Bury ◽  
M. Timko ◽  
P. Kopčanský
Keyword(s):  
Magnetic Fluids ◽  
Acoustic Attenuation ◽  
Transformer Oils

scholarly journals Acoustic Properties of Magnetic Fluids Based on Transformer Oil Under Magnetic Field

2013 ◽  
Vol 64 (6) ◽  
pp. 381-385 ◽  
Author(s):  
Jozef Kúdelčík ◽  
Peter Bury ◽  
Peter Kopčanský ◽  
Milan Timko ◽  
Vlasta Závišová
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Structural Changes ◽  
Magnetic Moments ◽  
Magnetic Fluids ◽  
Transformer Oil ◽  
Acoustic Properties ◽  
Acoustic Spectroscopy ◽  
Long Time ◽  
The Magnetic Field

Abstract The structural changes in magnetic fluids based on transformer oil TECHNOL and MOGUL upon the effect of an external magnetic field and temperature were studied by acoustic spectroscopy. When a magnetic field is increased, the interaction between the magnetic field and the magnetic moments of the nanoparticles leads to the aggregation of magnetic nanoparticles and following clusters formation. However, the temperature of magnetic fluids has also very important influence on the structural changes because of the mechanism of thermal motion that acts against the cluster creation. The live time of clusters have relative long time scale for the magnetic fluid based on TECHNOL, while for MOGUL is quite short.

scholarly journals Processing and Generalization of Experimental Data on Thermal Diffusivity and Thermal Conductivity of Magnetic Fluids Depending on the Impact of the Magnetic Field

2021 ◽  
Vol 27 (2) ◽  
pp. 231-237
Author(s):  
D. S. Dzhuraev
Keyword(s):  
Magnetic Field ◽  
Experimental Data ◽  
Thermal Conductivity ◽  
Thermal Diffusivity ◽  
Iron Powder ◽  
Experimental Studies ◽  
Magnetic Fluids ◽  
Transformer Oil ◽  
The Impact ◽  
The Magnetic Field

The paper presents the results of experimental studies of the thermal diffusivity and thermal conductivity of magnetic fluids based on transformer oil, depending on the effect of a magnetic field in the range of B = 1.59...3.866 mT, and the addition of iron powder 0.1...0.3 g with an interval of 0.05 g. Equations were obtained for calculation with a certain fraction of error in thermal diffusivity and thermal conductivity of unexplored magnetic fluids.

scholarly journals The Impact of Hydrogenation on Structural and Superconducting Properties of FeTe0.65Se0.35 Single Crystals

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7900
Author(s):  
Stanislav I. Bondarenko ◽  
Anatolij I. Prokhvatilov ◽  
Roman Puźniak ◽  
Jarosław Piętosa ◽  
Andrey A. Prokhorov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electron Paramagnetic Resonance ◽  
Single Crystals ◽  
Structural Changes ◽  
Superconducting Transition ◽  
Superconducting Properties ◽  
Paramagnetic Resonance ◽  
The Impact ◽  
Electron Paramagnetic ◽  
Diffusion Of Hydrogen

Properties of FeTe0.65Se0.35 single crystals, with the onset of critical temperature (Tconset) at 15.5 K, were modified via hydrogenation performed for 10–90 h, at temperatures ranging from 20 to 250 °C. It was found that the tetragonal matrix became unstable and crystal symmetry lowered for the samples hydrogenated already at 200 °C. However, matrix symmetry was not changed and the crystal was not destroyed after hydrogenation at 250 °C. Bulk Tcbulk, determined at the middle of the superconducting transition, which is equal to 12–13 K for the as grown FeTe0.65Se0.35, rose by more than 1 K after hydrogenation. The critical current density studied in magnetic field up to 70 kOe increased 4–30 times as a consequence of hydrogenation at 200 °C for 10 h. Electron paramagnetic resonance measurements also showed higher values of Tcbulk for hydrogenated crystals. Thermal diffusion of hydrogen into the crystals causes significant structural changes, leads to degeneration of crystal quality, and significantly alters superconducting properties. After hydrogenation, a strong correlation was noticed between the structural changes and changes in the parameters characterizing the superconducting state.

International trade: Research of the reasons for the fall

2019 ◽  
pp. 79-91 ◽  
Author(s):  
V. S. Nazarov ◽  
S. S. Lazaryan ◽  
I. V. Nikonov ◽  
A. I. Votinov
Keyword(s):  
Growth Rate ◽  
International Trade ◽  
Exchange Rate ◽  
Global Economy ◽  
Structural Changes ◽  
Global Value Chains ◽  
Value Chains ◽  
Negative Contribution ◽  
Basic Commodity ◽  
The Impact

The article assesses the impact of various factors on the growth rate of international trade. Many experts interpreted the cross-border flows of goods decline against the backdrop of a growing global economy as an alarming sign that indicates a slowdown in the processes of globalization. To determine the reasons for the dynamics of international trade, the decompositions of its growth rate were carried out and allowed to single out the effect of the dollar exchange rate, the commodities prices and global value chains on the change in the volume of trade. As a result, it was discovered that the most part of the dynamics of international trade is due to fluctuations in the exchange rate of the dollar and prices for basic commodity groups. The negative contribution of trade within global value chains in 2014 was also revealed. During the investigated period (2000—2014), such a picture was observed only in the crisis periods, which may indicate the beginning of structural changes in the world trade.

Solow economy model

2019 ◽  
pp. 150-157
Author(s):  
Oleksandr Synenko ◽  
Kateryna Yarema ◽  
Yuliia Bezsmertna
Keyword(s):  
Economic Growth ◽  
Regression Analysis ◽  
Solow Model ◽  
Economy Model ◽  
Accelerated Depreciation ◽  
Basic Parameters ◽  
The Subject ◽  
Investment Process ◽  
The Impact ◽  
Model Algorithm

The subject of the research is the approach to the possibility of using the Solow model to perform the regression analysis on the example of the Ukrainian economy model. The purpose of writing this article is to investigate the notion of regres- sion analysis, Solow’s economy model, algorithm for performing regression analy- sis on the example of Ukraine’s economy model. This model can be adapted for the economy of enterprises. Methodology. The research methodology is system-struc- tural and comparative analyzes (to study the structure of GDP); monograph (when studying methods of regression analysis on the example of the Ukrainian economy); economic analysis (when assessing the impact of factors on Ukraine’s GDP). The scientific novelty consists the features of the use of the Solow model on the ex- ample of Ukrainian economy are determined. An algorithm for calculating the basic parameters of a model using the Excel application package is disclosed. The main recommendations on the development of the national economy and economic growth through the use of macroeconomic instruments are given. Conclusions. The use of the Solow model enables forecasting and analysis. The results obtained re- vealed the problem of low resource return of capital as a resource, along with the means of macroeconomic regulation of the investment process, using which can improve the situation. A special place in these funds belongs to the accelerated depreciation and interest rate policies.

THE IMPACT OF UKRAINE'S EXCISE DUTY POLICY ON THE TRANSFORMATION PROCESSES OF THE TOBACCO MARKET

2020 ◽  
Vol 2020 (10) ◽  
pp. 19-33
Author(s):  
Nadiia NOVYTSKA ◽  
◽  
Inna KHLIEBNIKOVA ◽  
Keyword(s):  
Structural Changes ◽  
Tax Avoidance ◽  
Transformation Process ◽  
State Regulation ◽  
Tobacco Products ◽  
Excise Duty ◽  
Increasing Demand ◽  
High Level ◽  
The Impact ◽  
Transformation Processes

The market of tobacco products in Ukraine is one of the most dynamic and competitive. It develops under the influence of certain factors that cause structural changes, therefore, the aim of the article is to conduct a comprehensive analysis of transformation processes in the market of tobacco and their alternatives in Ukraine and identify the factors that cause them. The high level of tax burden and the proliferation of alternative products with a potentially lower risk to human health, including heating tobacco products and e-cigarettes, are key factors in the market’s transformation process. Their presence leads to an increase in illicit turnover of tobacco products, which accounts for 6.37% of the market, and the gradual replacement of cigarettes with alternative products, which account for 12.95%. The presence on the market of products that are not taxed or taxed at lower rates is one of the reasons for the reduction of excise duty revenues. According to the results of 2019, the planned indicators of revenues were not met by 23.5%. Other reasons for non-fulfillment of excise duty revenues include: declining dynamics of the tobacco products market; reduction in the number of smokers; reorientation of «cheap whites» cigarette flows from Ukraine to neighboring countries; tax avoidance. Prospects for further research are identified, namely the need to develop measures for state regulation and optimization of excise duty taxation of tobacco products and their alternatives, taking into account the risks to public health and increasing demand of illegal products.

Effekt of blood flow shutdown on the vein damage when exposed to HIFU

2017 ◽  
pp. 46-50
Author(s):  
Н.Н. Петрищев ◽  
Д.Ю. Семенов ◽  
А.Ю. Цибин ◽  
Г.Ю. Юкина ◽  
А.Е. Беркович ◽  
...  
Keyword(s):  
Blood Flow ◽  
Structural Changes ◽  
Focused Ultrasound ◽  
Vena Cava ◽  
Posterior Wall ◽  
High Intensity Focused Ultrasound ◽  
Vein Wall ◽  
Ultrasound Exposure ◽  
Isolated Segment ◽  
The Impact

The purpose. In the study we investigated the impact of the partial blood flow shutdown on structural changes in the rabbit vena cava posterior wall after exposure to high-intensity focused ultrasound (HIFU). Methods. Ultrasound Exposure: frequency of 1.65 MHz, the ultrasound intensity in the focus of 13.6 kW/cm, the area of the focal spot 1 mm, continuous ultrasound, exposure for 3 seconds. Results. Immediately after HIFU exposure all layers of the vein wall showed characteristic signs of thermal damage. A week after exposure structural changes in the intima, media and adventitia was minimal in the part of vessel with preserved blood flow, and after 4 weeks the changes were not revealed. A week after HIFU exposure partial endothelium destruction, destruction of myocytes, disorganization and consolidation of collagen fibers of the adventitia were observed in an isolated segment of the vessel, and in 4 weeks endothelium restored and signs of damage in media and adventitia persisted, but were less obvious than in a week after exposure. Conclusion. The shutdown of blood flow after exposure to HIFU promotes persistent changes in the vein wall. Vein compression appears to be necessary for the obliteration of the vessel, when using HIFU-technology.

Sign in / Sign up

Export Citation Format

Share Document