71 research outputs found
Effect of strain aging on physical and mechanical properties of austenitic chromium-nickel steel
The processes occurring in chromium-nickel steel 08Kh18N10T due to strain aging are studied. The tensile mechanical properties are determined. Relaxation tests and metallographic and x-ray diffraction analyses are performed. The internal energy state of the steel is estimated with the help of acoustic emissionyesBelgorod State Universit
Mechanical properties of mass-produced nanostructured titanium
The structure and mechanical properties of nanostructured titanium VT1-0 derived using an ingenious method which combines helical and longitudinal rolling are studied in comparison with the properties of commercial titanium alloys VT6 and VT16, as well as VT1-0 in a coarse-grained stateye
Magnetic Field Effects on the Far-Infrared Absorption in Mn_12-acetate
We report the far-infrared spectra of the molecular nanomagnet Mn_12-acetate
(Mn_12) as a function of temperature (5-300 K) and magnetic field (0-17 T). The
large number of observed vibrational modes is related to the low symmetry of
the molecule, and they are grouped together in clusters. Analysis of the mode
character based on molecular dynamics simulations and model compound studies
shows that all vibrations are complex; motion from a majority of atoms in the
molecule contribute to most modes. Three features involving intramolecular
vibrations of the Mn_12 molecule centered at 284, 306 and 409 cm-1 show changes
with applied magnetic field. The structure near 284 cm displays the
largest deviation with field and is mainly intensity related. A comparison
between the temperature dependent absorption difference spectra, the gradual
low-temperature cluster framework distortion as assessed by neutron diffraction
data, and field dependent absorption difference spectra suggests that this mode
may involve Mn motion in the crown.Comment: 5 pages, 4 figures, PRB accepte
Review of the Epidemiological Situation on Ixodic Tick-Borne Borrelioses in the Russian Federation in 2013ā2022 and Forecast for 2023
The aim of the review was to characterize the epidemiological situation on ixodic tick-borne borreliosis (ITBB) in the constituent entities of the Russian Federation in 2022, to forecast the development of the ITBB epidemic process in 2023 based on the analysis of its trends in the period of 2013ā2022. In total, 7 264 cases of ITBB were registered in the Russian Federation in 2022, which is 1.9 times higher than the 2021-value. In all regions in 2022, after a sharp decrease in the level of registered morbidity during the ācovidā phase of 2020ā2021, there was an incidence raise to the pre-pandemic level. During 2013ā2022, distinctive features of the trends in the development of the ITBB epidemic process in the territories of varying degree of epidemic hazard were retained. A downward tendency in the incidence rates was revealed in 14 out of 18 entities with a long-term average annual incidence (LTAA) of ITBB above 6.2 0 /0000, with the exception of Moscow and the Kaluga Region, where a further increase in the incidence of ITBB is possible. In 6 out of 16 regions with LTAA 2013ā2022 between 3.31 and 6.2 0 /0000, an upward trend was observed, and in 8 ā a decrease in morbidity. The trend towards an increase in morbidity was detected in 7 out of 21 entities with LTAA of ITBB from 1.21 to 3.3 0 /0000 and in 15 out of 26 regions with a low LTAA 2013ā2022 (below 1.2 0 /0000). The analysis of trends in the development of the ITBB epidemic process against the trends in changes in the frequency of contacts of the population with ticks, as well as calculations of the probable incidence rate allowed us to conclude that the incidence rate of ITBB in 2023 will range within the confidence intervals of long-term average annual values for the majority of the federal districts, with the exception of the Central Federal District, where an increase in the number of cases of ixodic tick-borne borreliosis is likely to occur, provided that the existing volumes of preventive measures are maintained and abnormal climatic phenomena absent. Effective control of the epidemic situation on the ITBB is attainable through preservation, and for such areas as Moscow, the Moscow Region, Voronezh, Kaluga, Orel, Ryazan, Penza and Rostov Regions, the Republic of Buryatia ā increase in the volume of preventive measures, strengthening zoological and entomological monitoring of activity and structure of natural foci. There is an obvious need to develop algorithms for molecular-genetic monitoring of pathogens circulating in natural foci, and to focus attention onto the problems of diagnosis and prophylaxis of tick-borne transmissible infections
Solar flare-related eruptions followed by long-lasting occultation of the emission in the He II 304 A line and in microwaves
Plasma with a temperature close to the chromospheric one is ejected in solar
eruptions. Such plasma can occult some part of emission of compact sources in
active regions as well as quiet solar areas. Absorption phenomena can be
observed in the microwave range as the so-called 'negative bursts' and also in
the He II 304 A line. The paper considers three eruptive events associated with
rather powerful flares. Parameters of absorbing material of an eruption are
estimated from multi-frequency records of a 'negative burst' in one event.
'Destruction' of an eruptive filament and its dispersion like a cloud over a
huge area observed as a giant depression of the 304 A line emission has been
revealed in a few events. One such event out of three ones known to us is
considered in this paper. Another event is a possibility.Comment: 23 pages, 8 figures, submitted for publication in Astronomy Report
Resetting single nanoparticle structural phase with nanosecond pulses
The authors demonstrate that transitions from high temperature phases to low temperature phases in a gallium nanoparticle can be stimulated by nanosecond optical pulses, and explain how this phenomenon could be used in a single nanoparticle all-optical memory
Effect of strain aging on physical and mechanical properties of austenitic chromium-nickel steel
yesThe processes occurring in chromium-nickel steel 08Kh18N10T due to strain aging are studied. The tensile mechanical properties are determined. Relaxation tests and metallographic and x-ray diffraction analyses are performed. The internal energy state of the steel is estimated with the help of acoustic emissionBelgorod State Universit
Mechanical properties of mass-produced nanostructured titanium
yesThe structure and mechanical properties of nanostructured titanium VT1-0 derived using an ingenious method which combines helical and longitudinal rolling are studied in comparison with the properties of commercial titanium alloys VT6 and VT16, as well as VT1-0 in a coarse-grained stat
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