Ferroelectric Behavior of Nano-Layered Heterostructures Composed of Ferroelectric - Linear Dielectric Organic Layers

Thin-film heterostructures comprising ferroelectric (FE) copolymer layers of vinylidene fluoride with trifluoroethylene (PVDF/TrFE) and linear dielectric (LD) layers of azodye prepared by Langmuir-Blodgett technique are obtained and studied. A simple physical model of a local electric field amplification in layers of FE and LD are presented. Experimental studies of the ferroelectric switching confirm that, for heterostructures, the external effective coercitive voltage decreases and the switched polarization increases. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3514

The world major scientific periodicals to be used by researchers of renewable energy, local and secondary energy resources

It is known that the selection of аn acceptably representative sample of the world scientific periodicals to be used as backgrounds of a high-quality research should focus not only on specialized journals, but also on periodicals, the topics and the titles of which are formally not related to the research area. In the pre-sent study the determination of the best periodicals to be used in research on renewable energy, local and secondary energy resources has been fulfilled with the aid of four varieties of citation analysis, twelve journals specialized in power production being used as the source items of citation data. The methods of the analysis were clarified and elaborated; the concept and the term "discipline receptivity factor" were proposed. The practical result is a list of 378 world periodicals, that is planned to be used in creating a comfortable scientific information environment by using the world leading databases reflect-ing the most valuable collection of scientific journals that are necessary for quality performance of scien-tific research on Priority areas of scientific-technical activity in the Republic of Belarus for 2016-2020 followed by the establishment of an operational system of selective alert informing prominent experts that implement the respective areas

Low-temperature spin relaxation in n-type GaAs

Low-temperature electron spin relaxation is studied by the optical orientation method in bulk n-GaAs with donor concentrations from 10^14 cm^{-3} to 5x10^17 cm^{-3}. A peculiarity related to the metal-to-insulator transition (MIT) is observed in the dependence of the spin lifetime on doping near n_D = 2x10^16 cm^{-3}. In the metallic phase, spin relaxation is governed by the Dyakonov-Perel mechanism, while in the insulator phase it is due to anisotropic exchange interaction and hyperfine interactio

Осложнения хирургического лечения пациентов со свежими переломами вертлужной впадины: систематический обзор

Background.The combination of classical anterior and posterior approaches, as well as their modifications, is recognized as the most effective in acetabular fractures surgical treatment. The use of classical and modified approaches is accompanied by  serious  intra-  and  postoperative  complications  associated  primarily  with  the  duration  of  surgery,  significant  blood loss, tissue trauma, surgical site infection. The aim of review — to determine the main and most frequent complications associated with surgical approaches to the acetabulum. material and methods. Access to literature sources is carried out in the information systems and databases PubMed/Medline, Embase, Scopus, Сochran Library, eLibrary, Wiley Online Library. Keywords: acetabular fractures, surgical treatment, approach to the acetabulum, total hip replacement.Results. The most common intraoperative complications are incorrect fragments reduction, sciatic nerve injury, less often — intraarticular implant position, damage to the superior gluteal artery and other vessels, among the early postoperative complications - wound infection, both superficial and deep, less often — venous thrombosis. Late postoperative complications are mainly represented  by  the  development  of  heterotopic  ossification,  post-traumatic  coxarthrosis,  less  often  revealed  aseptic necrosis of the femoral head, residual protrusion and secondary femoral head lesion. Conclusion. The main approach to the acetabulum are the ileo-inguinal and the Kocher-Langenbeck approach, as well as their combination.Complications were more common using two approaches, especially in cases of simultaneous use. The main intraoperative complications are the sciatic nerve and the superior gluteal artery injury with posterior approaches, the femoral lateral cutaneous nerve with expanded ilio-femoral approach, and the obturator nerve with anterior approaches.Введение. Наиболее эффективным в оперативном лечении переломов вертлужной впадины (ВВ) признан комбинированный подход с сочетанием классических передних и задних доступов, а также их модификаций. Применение классических и модифицированных доступов сопровождается возникающими серьезными интра- и послеоперационными осложнениями, связанными, прежде всего, с длительностью оперативного вмешательства, значительной кровопотерей, травматизацией тканей, развитием хирургической инфекции.Цель – определение основных и наиболее частых осложнений, связанных с применением хирургических доступов к вертлужной впадине.Материал и методы. Доступ к источникам литературы осуществлен в информационных системах и базах данных Pubmed, Embase, Scopus, Medline, Сochran Library, еLibrary, Wiley Online Library. Использованы ключевые слова: переломы вертлужной впадины, оперативное лечение, доступы к вертлужной впадине, эндопротезирование тазобедренного сустава. Результаты. Из интраоперационных осложнений чаще выявляются некорректная репозиция отломков, повреждение седалищного нерва, и реже – расположение части импланта в ВВ, повреждение верхней ягодичной артерии и других сосудов. Среди ранних послеоперационных осложнений отмечена раневая хирургическая инфекция, как поверхностная, так и глубокая, и реже венозные тромбозы. Поздние послеоперационные осложнения в основном представлены развитием гетеротопической оссификацией, посттравматическим коксартрозом, реже выявлялись асептический некроз голоски бедренной кости, остаточная протрузия и вторичное повреждение голоски бедренной кости. Заключение. Основными доступами к вертлужной впадине являются подвздошно-паховый и Кохера-Лангенбека, и их сочетание. Осложнения чаще встречались при использовании двух доступов, особенно в случаях одновременного их применения. Отмечена разновидность интраоперационных осложнений, ранних и поздних послеоперационных осложнений. Основными интраоперационными осложнениями являются повреждение седалищного нерва и верхней ягодичной артерии при задних доступах, бокового кожного нерва бедра при расширенном подвздошно-бедренном, запирательного нерва при передних доступах

Functioning of LIA-30 accelerator in the mode of generating bremsstrahlung pulses shortened to several nanoseconds

Deceleration of electrons and further transformation of the beam current lead to the ~2-times increase of the pulse amplitude, self-excited acceleration ofelectrons at the cutoffand shortening of15…20 Gy bremsstrahlung pulse.Гальмування електронів на фронті і наступна трансформація струму пучка приводять до збільшення амплітуди імпульсу у ~ 2 рази, до автоприскорення електронів на зрізі й укороченню імпульсу гальмового випромінювання з дозою 15…20 Гр.Торможение электронов на фронте и последующая трансформация тока пучка приводят к увеличению амплитуды импульса в ~ 2 раза, к автоускорению электронов на срезе и укорочению импульса тормозного излучения с дозой 15…20 Гр

Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters

Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review