373 research outputs found
Investigations of Bis-chromophore Systems: Relationship between Spectral Behaviour and Charge Transfer in 2-(3-coumaroyl)-benzopyrylium Perchlorates
The dependence of spectral properties and interfragmental charge transfer (ICT) on excitation, relaxation and excited state deactivation of 2-(3-coumaroyl)-benzopyrylium perchlorates has been analyzed. It was found that the positions of emission bands and rate constants of radiationless deactivation linearly correlate with ICT upon excited state deactivation, and Stokes’ shifts of fluorescence demonstrate linear dependence on ICT upon structural relaxation in the excited state
Laser beam welding of a CoCrFeNiMn-type high entropy alloy produced by self-propagating high-temperature synthesis
Fiber laser beam welding of a CoCrFeNiMn-type high entropy alloy (HEA) produced by self-propagating hightemperature synthesis (SHS) was reported in this work. The SHS-fabricated alloy was characterized by both ∼2 times reduced Mn content in comparison with that of the other principal components and the presence of impurities including Al, C, S, and S
Early fever detection on COVID-19 infection using thermoelectric module generators
In 2020 the COVID-19 pandemic has suddenly stopped society and changed human interaction. In this work, a thermoelectric generator wearable device for early fever detection symptoms is presented as a possible solution to avoid higher propagation of this disease. To identify a possible fever symptom, numerical and parametric simulations are developed using a highquality-refined hexahedral mesh. At first, a 2-pair-leg thermoelectric module has undergone simulations to establish temperature conditions, open-circuit voltage, and power output generation; and secondly, these previous results are extrapolated for a larger thermoelectric module containing 28 pair-leg of N-P type material. The numerical study shows that a maximum value of electrical power of 60.70 mW was reached for 28-pair-leg N-P type thermocouples under a constant temperature difference of 20 K
Regularities of the metallurgical industry restructuring process: Content, safety and regulation
The purpose of the work is to reveal the content, safety and regulation of the metallurgical industry restructuring. The objectives of the article are to generalize the theory and methods that characterize the essence of the designated industry restructuring regularities, the main directions of their safe implementation and regulation. The subject of the publication defines the organizational and economic relations arising during the implementation of the Russian metallurgy safe restructuring. The methodology of the study proceeds from objectively recurring significant relationships and dependencies that arise in the metallurgical industry restructuring process, the main link of its economy. The key results are reduced to determining a number of regularities of restructuring, its essence, features, priorities, clustering and ways of safe regulation by the state. Their scientific understanding is quite applicable both in educational institutions of the country when studying the theory and methodology of economic science, methods of restructuring of various sectors of the economy, and in real practice of structural changes at all levels of government. In conclusion, a number of findings are formed, reflecting both the content and safety of the restructuring of metallurgy and the corresponding laws, and the regulation of these processes
The ultraluminous GRB 110918A
GRB 110918A is the brightest long GRB detected by Konus-WIND during its 19
years of continuous observations and the most luminous GRB ever observed since
the beginning of the cosmological era in 1997. We report on the final IPN
localization of this event and its detailed multiwavelength study with a number
of space-based instruments. The prompt emission is characterized by a typical
duration, a moderare of the time-integrated spectrum, and strong
hard-to-soft evolution. The high observed energy fluence yields, at z=0.984, a
huge isotropic-equivalent energy release
erg. The record-breaking energy flux observed at the peak of the short, bright,
hard initial pulse results in an unprecedented isotropic-equivalent luminosity
erg s. A tail of the soft gamma-ray
emission was detected with temporal and spectral behavior typical of that
predicted by the synchrotron forward-shock model. Swift/XRT and Swift/UVOT
observed the bright afterglow from 1.2 to 48 days after the burst and revealed
no evidence of a jet break. The post-break scenario for the afterglow is
preferred from our analysis, with a hard underlying electron spectrum and
ISM-like circumburst environment implied. We conclude that, among multiple
reasons investigated, the tight collimation of the jet must have been a key
ingredient to produce this unusually bright burst. The inferred jet opening
angle of 1.7-3.4 deg results in reasonable values of the collimation-corrected
radiated energy and the peak luminosity, which, however, are still at the top
of their distributions for such tightly collimated events. We estimate a
detection horizon for a similar ultraluminous GRB of for Konus-WIND,
and for Swift/BAT, which stresses the importance of GRBs as probes of
the early Universe.Comment: 22 pages, 20 figures, accepted for publication in Ap
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