292 research outputs found
Origin of second-harmonic generation in the incommensurate phase of K2SeO4
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
Universal mechanism of discontinuity of commensurate-incommensurate transitions in three-dimensional solids: Strain dependence of soliton self-energy
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 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
Heat Treatment Condition Influence on Novokuibyshevsk Vacuum Residue Component Composition
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
Neural networks in transient ischemic attacks diagnostics
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
Historical and Legal Aspects of Participation of the Prosecutor in Civil Proceedings in the Russian Federation
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
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
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
EEG correlates of trait and mathematical anxiety during lexical and numerical error-recognition tasks
Визначення бактерицидних властивостей препарату “Сарофлокс” щодо музейних тест-культур мікроорганізмів
Everyone knows that test cultures are used to control and quality the growth properties of nutrient media, to check the activity of antiseptics and disinfectants, as well as to assess the adequacy of the sensitivity of the tested microorganisms to new antibacterial drugs, which are currently produced by rapid temp. with the development of antibiotic resistance of microorganisms to most of the active substances used in new drugs. Moreover, it is the understanding that most antibiotics are clinically useless in treating infectious diseases because of their long-term use for chemotherapy purposes – a major problem not only in Ukraine but worldwide. In this article the results of researches sensitivity museum strains, namely: Escherichia coli ATCC 25922 (F-50), Pseudomonas aeruginosa ATCC 2853 (F), Proteus vulgaris HX 19 number 222, Staphylococcus aureus ATCC 25923, Enterobacter aerogenes 10006, Enterococcus faecalis ATCC 19433 to the antibacterial drug “Saroflox”. We find that Saroflox inhibited the growth of all test cultures at different dilution rates. Using different concentrations of the antibiotic (2.5 mg, 1.25 mg, 0.625 mg, 0.3125 mg, 0.1562/200 μl), it was found that all test cultures under study were highly sensitive to Saroflox. most from 38.0 ± 1.0 to 20.0 ± 1.0 mm. The results of studies show that the new antibacterial drug “Saroflox” has bactericidal properties to most cultures that cause bacterial diseases of various species of animals and birds, which only confirms its effectiveness against gram-negative microorganisms (Enterobacter spp. , Staphylococcus aureus E. coli and others) including beta-lactam antibiotic resistant, tetracyclines, macrolides and aminoglycosides.Всім відомо, що тест-культури використовують для контролю і якості ростових властивостей живильних середовищ, для перевірки активності антисептиків і дезінфектантів, а також для оцінки адекватності проведення методик чутливості досліджуваних мікроорганізмів до нових антибактеріальних препаратів, які нині виробляються стрімкими темпами у зв’язку з розвитком антибіотикорезистентності мікроорганізмів до більшості застосовуваних активно діючих речовин нових препаратів. І саме розуміння того, що більшість антибіотиків є клінічно марними в лікуванні інфекційних хвороб через довготривале їхнє застосування з хіміотерапевтичною метою – велика проблема не тільки в Україні а й в усьому світі. У нашій статті наведено результати досліджень чутливості музейних штамів мікроорганізмів, а саме: Escherichia coli ATCC 25922 (F-50), Pseudomonas aeruginosa ATCC 2853 (F), Proteus vulgaris HX 19 № 222, Staphylococcus aureus ATCC 25923, Enterobacter aerogenes 10006, Enterococcus faecalis ATCC 19433 до антибактеріального препарату “Сарофлокс”. Нами встановлено, що “Сарофлокс” пригнічував ріст всіх дослідних тест-культур в різному ступені розведення. Використовуючи при цьому різну концентрацію антибіотика (2,5 мг, 1.25 мг, 0,625 мг, 0,3125 мг, 0,1562/200мкл) було встановлено що всі досліджувані тест-культури проявляли високу чутливість до препарату “Сарофлокс” зона затримки яких становила здебільшого від 38,0 ± 1,0 до 20,0 ± 1,0 мм. В результаті отриманих досліджень можна сказати, що новий антибактеріальний препарат “Сарофлокс” володіє бактерицидними властивостями до більшості культур, які спричиняють бактеріальні захворювання різних видів тварин і птиці, що лише підтверджує його ефективність до грамнегативних мікроорганізмів (Enterobacter spp., Pseudomonas spp., Streptococcus spp., Staphylococcus aureus E. coli та ін.), в тому числі резистентних до бета-лактамних антибіотиків, тетрациклінів, макролідів та аміноглікозидів
Precise Half-Life Measurement of the Superallowed Beta+ Emitter 26Si
We have measured the half-life of the superallowed 0+ -to- 0+ beta+ emitter
26Si to be 2245.3(7) ms. We used pure sources of 26Si and employed a
high-efficiency gas counter, which was sensitive to positrons from both this
nuclide and its daughter 26mAl. The data were analyzed as a linked
parent-daughter decay. To contribute meaningfully to any test of the unitarity
of the Cabibbo-Kobayashi-Maskawa (CKM) matrix, the ft value of a superallowed
transition must be determined to a precision of 0.1% or better. With a
precision of 0.03% the present result is more than sufficient to be compatable
with that requirement. Only the branching ratio now remains to be measured
precisely before a +/-0.1% ft value can be obtained for the superallowed
transition from 26Si
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