scholarly journals The simulation of vibrational populations of electronically excited N2and O2molecules in the middle atmosphere of the Earth during precipitations of high-energetic particles.

2020 ◽  
Author(s):  
A.S. Kirillov ◽  
◽  
R. Werner ◽  
V. Guineva ◽  
◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Electronic Excitation ◽  
Middle Atmosphere ◽  
Molecular Nitrogen ◽  
Inelastic Collisions ◽  
Transfer Processes ◽  
The Earth ◽  
Electronically Excited ◽  
Kinetics Of

We study the electronic kinetics of molecular nitrogen and molecular oxygen in the middle atmosphere of the Earth during precipitations of high-energetic protons and electrons.The role of molecular inelastic collisions in intermolecularelectron energy transfer processes is investigated.It is shown that inelastic molecular collisions influence on vibrational populations of electronically excited molecular oxygen. It is pointed out on very important role of the collisions of N2(A3u+) with O2molecules on the electronic excitation of Herzberg states of molecular oxygenat the altitudes of the middle atmosphere.

scholarly journals Mechanism of the Formation of Electronically Excited Species by Oxidative Metabolic Processes: Role of Reactive Oxygen Species

Biomolecules ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 258 ◽  
Author(s):  
Pavel Pospíšil ◽  
Ankush Prasad ◽  
Marek Rác
Keyword(s):  
Reactive Oxygen Species ◽  
Molecular Oxygen ◽  
Reactive Oxygen ◽  
High Energy ◽  
Oxygen Species ◽  
Human Beings ◽  
Metabolic Processes ◽  
Excited Species ◽  
Electronically Excited

It is well known that biological systems, such as microorganisms, plants, and animals, including human beings, form spontaneous electronically excited species through oxidative metabolic processes. Though the mechanism responsible for the formation of electronically excited species is still not clearly understood, several lines of evidence suggest that reactive oxygen species (ROS) are involved in the formation of electronically excited species. This review attempts to describe the role of ROS in the formation of electronically excited species during oxidative metabolic processes. Briefly, the oxidation of biomolecules, such as lipids, proteins, and nucleic acids by ROS initiates a cascade of reactions that leads to the formation of triplet excited carbonyls formed by the decomposition of cyclic (1,2-dioxetane) and linear (tetroxide) high-energy intermediates. When chromophores are in proximity to triplet excited carbonyls, the triplet-singlet and triplet-triplet energy transfers from triplet excited carbonyls to chromophores result in the formation of singlet and triplet excited chromophores, respectively. Alternatively, when molecular oxygen is present, the triplet-singlet energy transfer from triplet excited carbonyls to molecular oxygen initiates the formation of singlet oxygen. Understanding the mechanism of the formation of electronically excited species allows us to use electronically excited species as a marker for oxidative metabolic processes in cells.

scholarly journals On the role of ‘hot’ atoms in plasma-assisted ignition

2015 ◽  
Vol 373 (2048) ◽  
pp. 20140343 ◽  
Author(s):  
Andrey Yu Starikovskiy
Keyword(s):  
Initial Distribution ◽  
Translational Energy ◽  
Collisional Quenching ◽  
Active Components ◽  
Temperature Oxidation ◽  
Electronically Excited ◽  
Ignition Threshold ◽  
Kinetics Of ◽  
Non Equilibrium

This paper discusses the processes leading to the formation of ‘hot’ atoms and radicals possessing excessive translational energy in high-voltage NS pulse discharges. It is shown that the formation of such ‘hot’ atoms occurs efficiently both in the dissociation of molecules by direct electron impact, and in the collisional quenching of electronically excited states. Depending on the magnitude of the reduced electric field in the discharge, reactions of these ‘hot’ atoms increase the initial concentration of radicals in the discharge afterglow two to three times when compared with the values calculated without effects of translational non-equilibrium. The role of thermally non-equilibrium excitation has been demonstrated in the formation of the initial distribution of the chemically active components in the mixture and its influence on the kinetics of ignition initiation at low and high temperatures. It was found that in undiluted mixtures the presence of ‘hot’ atoms can significantly decrease an ignition threshold and accelerate a low-temperature oxidation.

Longitudinal Relaxation Time Measurements in Hydrogen Gas Mixtures at Low Densities

1975 ◽  
Vol 53 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Robin L. Armstrong ◽  
Kenneth E. Kisman ◽  
Wallace Kalechstein
Keyword(s):  
Relaxation Time ◽  
Spin Relaxation ◽  
Nuclear Spin ◽  
Molecular Nitrogen ◽  
Hydrogen Gas ◽  
Inelastic Collisions ◽  
Nuclear Spin Relaxation ◽  
Longitudinal Relaxation Time ◽  
Preliminary Information

Measurements of the longitudinal nuclear spin relaxation time through the region of the characteristic minimum at 49 MHz in mixtures of molecular hydrogen with the noble gases helium and argon and with molecular nitrogen are reported at 298 K. The data obtained serve as a further test of the basic approximations in the Bloom–Oppenheim theory and provide preliminary information concerning the role of inelastic collisions in the nuclear spin relaxation process.

Luminescence of Molecular Nitrogen and Molecular Oxygen in the Earth’s Middle Atmosphere During the Precipitation of High-Energy Protons

2021 ◽  
Vol 61 (6) ◽  
pp. 864-870
Author(s):  
A. S. Kirillov ◽  
V. B. Belakhovsky ◽  
E. A. Maurchev ◽  
Yu. V. Balabin ◽  
A. V. Germanenko ◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Middle Atmosphere ◽  
Molecular Nitrogen ◽  
High Energy

Kinetics of oxidation of benzyl alcohols with molecular oxygen catalyzed by N ‐hydroxyphthalimide: Role of hydroperoxyl radicals

2019 ◽  
Vol 51 (9) ◽  
pp. 679-688
Author(s):  
I. A. Opeida ◽  
R. B. Sheparovych ◽  
Yu. M. Hrynda ◽  
O. Yu. Khavunko ◽  
M. O. Kompanets ◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Benzyl Alcohols ◽  
Kinetics Of Oxidation ◽  
Kinetics Of

scholarly journals Electronic kinetics of molecular nitrogen and molecular oxygen in high-latitude lower thermosphere and mesosphere

2010 ◽  
Vol 28 (1) ◽  
pp. 181-192 ◽  
Author(s):  
A. S. Kirillov
Keyword(s):  
Molecular Oxygen ◽  
High Latitude ◽  
Molecular Nitrogen ◽  
Lower Thermosphere ◽  
Rate Coefficients ◽  
Triplet States ◽  
Quenching Rate ◽  
Principal Mechanism ◽  
Auroral Electron ◽  
Electronically Excited

Abstract. Total quenching rate coefficients of Herzberg states of molecular oxygen and three triplet states of molecular nitrogen in the collisions with O2 and N2 molecules are calculated on the basis of quantum-chemical approximations. The calculated rate coefficients of electronic quenching of O2* and N2* molecules show a good agreement with available experimental data. An influence of collisional processes on vibrational populations of electronically excited N2 and O2 molecules is studied for the altitudes of high-latitude lower thermosphere and mesosphere during auroral electron precipitation. It is indicated that molecular collisions of metastable nitrogen N2(A3Σu*) with O2 molecules are principal mechanism in electronic excitation of both Herzberg states c1Σu&minus, A'3Δu, A3Σu+ and high vibrational levels of singlet states a1Δg and b1Σg+ of molecular oxygen O2 at these altitudes.

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