136 research outputs found

    Octupole correlations near 110Te

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    The lifetime of the 2+ and 9-, 11-, 13-, 15- states in the neutron-deficient 110Te was measured for the first time using the recoil distance Doppler shift technique. The reported value of the reduced transition probability B(E2;0+g.s?2+)=4.3(8)×103e2fm4 supports the systematic for even-mass Te isotopes and was interpreted in the framework of the large-scale shell model and cranked shell model calculations. The measured reduced transition probabilities in the negative-parity yrast band revealed the upward trend towards the high spins. The enhanced collectivity is discussed in terms of the tilted axis cranking approach and the symmetry configuration mixing method with the Gogny D1S interaction.The authors would like to thank the technical staff of the LNL Legnaro facility for their assistance in providing excellent operation of the XTU-tandem accelerator. The authors wish to acknowledge the support of local engineers P. Cocconi and R. Isocrate. The work was partially supported by the DoE Grant No. DE-FG02-95ER4093 and Spanish MICINN Grant No. PGC2018-094583-B-I00

    THE CASCADE PHASE CHANGE HEATING STORAGE

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    This paper discusses the prospects for using a cascade phase change heating storage tank to reduce heat losses and increase efficiency during the operation of space heating and do-mestic hot water.Авторы выражают благодарность Правительству Московской области за финансирование проекта в рамках гранта Губернатора Московской области по договору №33 от 24.07.2020

    Is there a dark decay of neutrons in 6^6He ?

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    Motivated by the four standard deviations discrepancy between the mean values for the neutron lifetime obtained from beam and bottle experiments, we have searched for a hypothetical neutron dark decay in 6^6He nuclei through the channel 6He4He+n+χ^6{\rm He} \rightarrow ^4{\rm He}+n+\chi. The experiment used a 25~keV high intensity 6^6He+^+ beam with a high efficiency neutron detector. The search for a signal correlated with the 6^6He activity in the neutron detection rate resulted in a branching ratio Brχ4.0×1010{\rm Br}_\chi \leq 4.0\times10^{-10} with a 95\% C.L. over the mass window 937.993<mχ<mn0.975937.993 < m_\chi < m_n-0.975 MeV. This result is five orders of magnitude smaller than required to solve the neutron lifetime discrepancy

    First Evidence of Shape Coexistence in the Ni-78 Region : Intruder 0(2)(+) State in Ge-80

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    The N = 48 Ge-80 nucleus is studied by means of beta-delayed electron-conversion spectroscopy at ALTO. The radioactive Ga-80 beam is produced through the isotope separation on line photofission technique and collected on a movable tape for the measurement of gamma and e(-) emission following beta decay. An electric monopole E0 transition, which points to a 639(1) keV intruder 0(2)(+) state, is observed for the first time. This new state is lower than the 2(1)(+) level in Ge-80, and provides evidence of shape coexistence close to one of the most neutron-rich doubly magic nuclei discovered so far, Ni-78. This result is compared with theoretical estimates, helping to explain the role of monopole and quadrupole forces in the weakening of the N = 50 gap at Z = 32. The evolution of intruder 0(2)(+) states towards Ni-78 is discussed.Peer reviewe

    DEVELOPMENT OF A HARDWARE-SOFTWARE COMPLEX FOR STUDYING PHASE TRANSITIONS OF SUBSTANCES DURING THE COOLING

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    The work is devoted to the development of a hardware-software complex for studying the phase transitions of substances during cooling and calculating the main physical and chemical characteristics of substances

    Synthesis and Research Phase Change Materials Based on a Hydrate Salt Zn(NO3)2·6H2O Composite

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    This work is devoted to the synthesis of heat storage materials based on zinc nitrate hexahydrate, the study of their thermophysical characteristics and the study of thermal stability in the cyclic heating/cooling mode.Данные исследования выполнены при поддержке Фонда содействия развитию малых форм предприятий в научно-технической сфере (FASIE)

    Unexpected high-energy γ emission from decaying exotic nuclei

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    Abstract The N = 52 Ga 83 β decay was studied at ALTO. The radioactive 83Ga beam was produced through the ISOL photofission technique and collected on a movable tape for the measurement of γ-ray emission following β decay. While β-delayed neutron emission has been measured to be 56–85% of the decay path, in this experiment an unexpected high-energy 5–9 MeV γ-ray yield of 16(4)% was observed, coming from states several MeVs above the neutron separation threshold. This result is compared with cutting-edge QRPA calculations, which show that when neutrons deeply bound in the core of the nucleus decay into protons via a Gamow–Teller transition, they give rise to a dipolar oscillation of nuclear matter in the nucleus. This leads to large electromagnetic transition probabilities which can compete with neutron emission, thus affecting the β-decay path. This process is enhanced by an excess of neutrons on the nuclear surface and may thus be a common feature for very neutron-rich isotopes, challenging the present understanding of decay properties of exotic nuclei

    Моделирование условий и результатов внедрения укороченных режимов лечения больных туберкулезом

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    The objective: to study the conditions of implementation of short-course (4 and 9 months) treatment regimens in tuberculosis patients and simulate their impact on the frequency of early treatment interruption (ETI) by patients.Subjects and Methods. Data on the treatment duration from enrollment to chemotherapy interruption in 8,029 tuberculosis patients were studied. Data were obtained from the Federal Register of Tuberculosis Cases for 2020. Of these, 3,379 patients were treated with regimens for susceptible or suspected susceptible tuberculous mycobacteria excluding isoniazid resistant tuberculosis, and 4,650 patients received regimens for rifampicin-resistant tuberculous mycobacteria.Results. The median duration of treatment from onset to ETI was 124 (95% CI 120-128) days in 3,379 patients, 224 (95% CI 215-233) days in 4,650 patients, or 170 (95% CI 157-181) days if there was a history of treatment interruption. Simulation of ETI terms when short-course chemotherapy regimens were introduced has shown that we can expect a 2-fold decrease in the proportion of patients who interrupted chemotherapy among patients with preserved/suspected susceptibility of tuberculous mycobacteria, and 1.3-1.7-fold decrease among patients with confirmed/presumed drug resistance of tuberculous mycobacteria at least to rifampicin.Цель исследования: изучить условия внедрения укороченных (4 и 9 месяцев) режимов лечения больных туберкулезом и провести моделирование их влияния на частоту досрочного прерывания лечения (ДПЛ) пациентами.Материалы и методы. Изучены сведения о продолжительности лечения от регистрации до прерывания курса химиотерапии у 8029 больных туберкулезом. Данные получены из «Федерального регистра лиц, больных туберкулезом» за 2020 год. Из них 3379 пациентов лечились по режимам для больных с сохраненной или предполагаемой лекарственной чувствительностью МБТ, исключая изониазид-устойчивый туберкулез, и 4650 – по режимам для больных с лекарственной устойчивостью МБТ к рифампицину.Результаты. Медиана продолжительности лечения от начала до ДПЛ у 3379 больных составила 124 (95% CI 120-128) дня, у 4650 – 224 (95%CI 215-233) дня или 170 (95%CI 157-181) дней при наличии прерывания лечения в анамнезе. Моделирование сроков ДПЛ при внедрении укороченных режимов химиотерапии показало, что можно ожидать снижение доли больных, прервавших курс химиотерапии в 2 раза среди пациентов с сохраненной/предполагаемой лекарственной чувствительностью МБТ, и в 1,3-1,7 раза среди пациентов с установленной/предполагаемой лекарственной устойчивостью МБТ как минимум к рифампицину
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