29 research outputs found

    Structural and electrical transport properties of superconducting Au{0.7}In{0.3} films: A random array of superconductor-normal metal-superconductor (SNS) Josephson junctions

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    The structural and superconducting properties of Au{0.7}In{0.3} films, grown by interdiffusion of alternating Au and In layers, have been studied. The films were found to consist of a uniform solid solution of Au{0.9}In{0.1}, with excess In precipitated in the form of In-rich grains of various Au-In phases (with distinct atomic compositions), including intermetallic compounds. As the temperature was lowered, these individual grains became superconducting at a particular transition temperature (Tc), determined primarily by the atomic composition of the grain, before a fully superconducting state of zero resistance was established. From the observed onset Tc, it was inferred that up to three different superconducting phases could have formed in these Au{0.7}In{0.3} films, all of which were embedded in a uniform Au{0.9}In{0.1} matrix. Among these phases, the Tc of a particular one, 0.8 K, is higher than any previously reported for the Au-In system. The electrical transport properties were studied down to low temperatures. The transport results were found to be well correlated with those of the structural studies. The present work suggests that Au{0.7}In{0.3} can be modeled as a random array of superconductor-normal metal-superconductor (SNS) Josephson junctions. The effect of disorder and the nature of the superconducting transition in these Au{0.7}In{0.3} films are discussed.Comment: 8 text pages, 10 figures in one separate PDF file, submitted to PR

    Ultrasonic extraction of amaranth oils

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    The isolation of biologically active substances - extraction, is currently the most difficult and time-consuming task that can be solved only in the conditions of large productions with the help of specialized equipment, and practically impossible at home. As numerous studies show, from the natural raw material of plant and animal origin it is possible to extract practically all known compounds, which are produced by plants [1]. The authors carried out extraction of amaranth in cold pressed olive oil. Since it is close in composition with amaranth oil. The biological activity of the oil is due to the presence of squalene and tocotrienol, and the percentage of their various fractions possessing antioxidant properties

    Ultrasonic extraction of flax polysaccharides

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    To date, flax is one of the most promising crops that are dynamically developing. The demand for flax and products of its processing in Ukraine and other countries is due to increased interest in its use in medicine, cooking and cosmetology [1]. The main nutrients that determine the biological activity of flaxseed are protein substances, vitamins, enzymes, carbohydrates and fatty oils, which include glycerides of linoleic (35-45%), linoleic (25-35%), oleinic (15-20% ), stearic acid (8-9%). In our time, from flax seeds on an industrial scale only oil is obtained, using one of the traditional mechanical methods. According to the biological value, oil from flaxseed oil occupies the first place among other edible vegetable oils and contains a lot of substances useful for the body (polyunsaturated acids, vitamins F, A, E, K, saturated fatty acids (10% composition). Flaxseed oil is excellent a source of valuable polyunsaturated fatty acids ω-3 and ω-6 (the human body can not independently synthesize these valuable acids). The aim of the work is to study the methods of obtaining and application of flax polysaccharides, as well as the development of energy-efficient technology for their obtaining. The conducted researches have shown, that at application of ultrasonic processing in the process of extraction of flax polysaccharides the extraction time is significantly reduced. The maximum yield of polysaccharides takes place with ultrasound processing of extraction capacity of 70 W / m2 for 20 minutes. The flax polysaccharides obtained in this way can be successfully used as antioxidant, bactericidal, fungicidal and antiviral drugs

    Geometrical destruction of the global phase coherence in ultrathin superconducting cylinders

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    The global phase coherence in doubly-connected superconductors leads to fluxoid quantization, allowing the superfluid velocity vs to be controlled by an applied magnetic flux. In ultrasmall samples this quantization requirement leads, surprisingly, to the destruction of the phase coherence itself around half-integer flux quanta, because of the sample-size-induced growth in vs, as predicted by de Gennes. We report observations of the predicted phenomenon in ultrathin Al and Au0.7In0.3 cylinders, and the corresponding phase diagram for ultrathin superconducting cylinders. The new phase diagram features disconnected superconducting regions, as opposed to the single one seen in the conventional Little-Parks experiment.Comment: pdf file, 9 pages plus 5 figure

    Ultrasonic extraction of amaranth oils

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    Chulak L. D., Zadorozhny V. G., Chulak Yu. L., Chulak O. T., Tatarina O. V. Ultrasonic extraction of amaranth oils. Journal of Education, Health and Sport. 2018;8(8):1227-1235. eISNN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.1465021 http://ojs.ukw.edu.pl/index.php/johs/article/view/6203 The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part b item 1223 (26/01/2017). 1223 Journal of Education, Health and Sport eISSN 2391-8306 7 © The Author(s) 2018; This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author (s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non commercial license (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. This is an open access article licensed under the terms of the Creative Commons Attribution Non commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. The authors declare that there is no conflict of interests regarding the publication of this paper. Received: 02.08.2018. Revised: 14.08.2018. Accepted: 31.08.2018. Ultrasonic extraction of amaranth oils L. D. Chulak, V. G. Zadorozhny, Yu. L. Chulak, O. T. Chulak, O. V. Tatarina International Humanitarian University, Оdesa Abstract The isolation of biologically active substances - extraction, is currently the most difficult and time-consuming task that can be solved only in the conditions of large productions with the help of specialized equipment, and practically impossible at home. As numerous studies show, from the natural raw material of plant and animal origin it is possible to extract practically all known compounds, which are produced by plants [1]. The authors carried out extraction of amaranth in cold pressed olive oil. Since it is close in composition with amaranth oil. The biological activity of the oil is due to the presence of squalene and tocotrienol, and the percentage of their various fractions possessing antioxidant properties. Key words: amaranth oil, ultrasonic extraction, squalen

    A New Interpretation of Flux Quantization

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    We study the effect of Aharonov-Bohm flux on the superconducting state in metallic cylinders. Although Byers and Yang attributed flux quantization to the flux-dependent minimum of kinetic energies of the Cooper pairs, it is shown that kinetic energies do not produce any discernible oscillations in the free energy of the superconducting state (relative to that of normal state) as a function of the flux. This result is indeed anticipated by the observation of persistent current in normal metal rings at low temperature. Instead, we have found that pairing interaction depends on the flux, leading to flux quantization. When the flux (Φ(\Phi) is given by Φ=n×hc/2e\Phi=n\times hc/2e (with integer n), the pairing interaction and the free energy become unchanged (even n) or almost unchanged (odd n), due to degenerate-state pairing resulting from the energy level crossing. As a result, flux quantization and Little-Parks oscillations follow.Comment: Revtex, 10 pages, 6 figures, For more information, send me an e-mail at [email protected]
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