372 research outputs found

    Origin of second-harmonic generation in the incommensurate phase of K2SeO4

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    We show that a ferroelectric phase transition takes place in the incommensurate phase of the K2SeO4 crystal. The ferroelectric character of the IC phase explains the second-harmonic generation observed in the corresponding temperature range.Comment: 5 pages, 1 figur

    Neural networks in transient ischemic attacks diagnostics

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    Секция 2. Интеллектуальные информационные системыIn this paper the neural network model for transient ischemic attacks recognition have been addressed. The proposed approach is based on integration of the NPCA neural network and multilayer perceptron. The dataset from clinic have been used for experiments performing. Combining two different neural networks (NPCA and MLP) it is possible to produce efficient performance in terms of detection and recognition transient ischemic attacks. The main advantages of using neural network techniques are the ability to recognize “novel” TIA attack instances, quickness and ability to assist the doctor in making decision

    Half-life of the electron-capture decay of 97Ru: Precision measurement shows no temperature dependence

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    We have measured the half-life of the electron-capture (ec) decay of 97Ru in a metallic environment, both at low temperature (19K), and also at room temperature. We find the half-lives at both temperatures to be the same within 0.1%. This demonstrates that a recent claim that the ec decay half-life for 7Be changes by $0.9% +/- 0.2% under similar circumstances certainly cannot be generalized to other ec decays. Our results for the half-life of 97Ru, 2.8370(14)d at room temperature and 2.8382(14)d at 19K, are consistent with, but much more precise than, previous room-temperature measurements. In addition, we have also measured the half-lives of the beta-emitters 103Ru and 105Rh at both temperatures, and found them also to be unchanged.Comment: 6 pages, 6 figure

    Heat Treatment Condition Influence on Novokuibyshevsk Vacuum Residue Component Composition

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    The article presents the information about thermal degradation of Novokuibyshevsk vacuum residue and change of products composition during this process. The optimal conditions for the thermal destruction of vacuum residue components were established. The regularities of material balance composition change, Sgeneral were determined depending on cracking conditions. The basic directions of resin-asphaltene component transformations were identified, changes in their structural-group parameters in the process of initiated cracking were analyzed. Conducting of Novokuibyshevsk vacuum residue thermolysis leads to deep resins-asphaltenes average molecules structure characteristic changes. Developed alkyl and naphthenic moieties, which are presented in initial molecule, undergo degradation, amount of structural blocks in resins and asphaltenes molecules reduces, their average size decreases. Also the reduction in total content of the rings (saturated and aromatic) was established in average structural unit, at the same time decrease of rings substitution and length of the aliphatic fragments can be observed. In general the process of vacuum residue thermal cracking causes partial degradation of saturated (aliphatic and naphthenic) fragments and, partially, aromatic rings, which contain heteroatomic elements

    Universal mechanism of discontinuity of commensurate-incommensurate transitions in three-dimensional solids: Strain dependence of soliton self-energy

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    We show that there exists a universal mechanism of long-range soliton attraction in three-dimensional solids and, therefore, of discontinuity of any commensurate-incommensurate (C-IC) phase transition. This mechanism is due to the strain dependence of the soliton self-energy and specific features of the solid-state elasticity. The role of this mechanism is studied in detail for a class of C-IC transitions where the IC modulation is one-dimensional, the anisotropy in the order parameter space is small, and the symmetry of the systems allows the existence of the Lifshitz invariant. Two other mechanisms of soliton attraction are operative here but the universal mechanism considered in this paper is found to be the most important one in some cases. Comparison with the most extensively studied C-IC transition in K2SeO4\rm K_2SeO_4 shows that the experimentally observed thermal anomalies can be understood as a result of the smearing of the theoretically predicted discontinuous transition.Comment: 8 pages (extended version, title changed

    Historical and Legal Aspects of Participation of the Prosecutor in Civil Proceedings in the Russian Federation

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    The article is devoted to the study of the development of the legal framework of participation of the Prosecutor in civil cases by the courts since the establishment of the posts of prosecutors in 1722 also Dedicated two new historical conditions, when the prosecution was re-established and empowered to participate in the consideration of cases in courts. Analyzed the reasons for the creation of the prosecution, the powers of prosecutors, the relationship of prosecutors and courts

    Composition of Initiated Cracking Products of High-sulfur Natural Bitumen

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    The analysis of the cracking products of bitumen Karmalskoye deposits (the content of fractions boiling up to 200 °C 6,7% wt.) has been performed. The influence of power plant coal ash microspheres on orientation of cracking bitumen components is stated. Bitumen cracking leads to significant yields of gas and coke for more than 20% wt. and destructions of all components. The initiated bitumen cracking in the presence of 10% microspheres at cracking temperature 450 °C leads to reduction of gas and coke yields and increase in fractions of ibp (initial boiling point) –360 °C at 10% wt. in comparison with products of the thermal bitumen cracking. The analysis of composition and amount of sulfur compounds in initial bitumen and the cracking products in the various conditions has shown that the thermal cracking leads to increased homologues benzothiophene contents due to partial destruction of resins, and to decrease in the content of homologues dibenzothiophene

    Composition of Pre-ozonated High-Sulfur Natural Bitumen Cracking Products

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    The results analysis of fractional and material composition of the cracking products of Ashalchinskoye and Karmalskoye bitumen deposits was presented in this work. The effect of bitumen ozone-oxygen mixture pretreatment followed by cracking on thermolysis processes was investigated. It was shown that molecules of resins and asphaltenes containing large amounts of aliphatic fragments in its structure readily undergo thermal decomposition to form additional distillate fractions. Low content of aliphatic fragments leads to aromatization of the naphthenic cycles in the molecule of resins and asphaltenes, the thermal degradation reactions proceed in high yields of gas and coke

    Precise Half-Life Measurement of the Superallowed beta emitter 10C

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    The half-life of 10C has been measured to be 19.310(4)s, a result with 0.02% precision, which is a factor of three improvement over the best previous result. Since 10C is the lightest superallowed 0+ --> 0+ beta emitter, its ft value has the greatest weight in setting an upper limit on the possible presence of scalar currents.Comment: 4 pages, 3 figure

    Precision measurements of the 60^{60}Co β\beta-asymmetry parameter in search for tensor currents in weak interactions

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    The β\beta-asymmetry parameter A~\widetilde{A} for the Gamow-Teller decay of 60^{60}Co was measured by polarizing the radioactive nuclei with the brute force low-temperature nuclear-orientation method. The 60^{60}Co activity was cooled down to milliKelvin temperatures in a 3^3He-4^4He dilution refrigerator in an external 13 T magnetic field. The β\beta particles were observed by a 500 μm{\mu}m thick Si PIN diode operating at a temperature of about 10 K in a magnetic field of 0.6 T. Extensive GEANT4 Monte-Carlo simulations were performed to gain control over the systematic effects. Our result, A~=1.014(12)stat(16)syst\widetilde{A} = -1.014(12)_{stat}(16)_{syst}, is in agreement with the Standard-Model value of 0.987(9)-0.987(9), which includes recoil-order corrections that were addressed for the first time for this isotope. Further, it enables limits to be placed on possible tensor-type charged weak currents as well as other physics beyond the Standard Model
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