Low energy resonance states of negative molecular ions. Five-membered ring heterocycles and cyclopentadiene

1990 ◽  
Vol 26 (2) ◽  
pp. 240-241
Author(s):  
M. V. Muftakhov ◽  
V. A. Mazunov ◽  
V. I. Khvostenko
Keyword(s):  
Molecular Ions ◽  
Membered Ring ◽  
Low Energy ◽  
Resonance States ◽  
Energy Resonance

Low-energy resonance states upon electron capture by five-membered heterocycles and cyclopentadiene

1990 ◽  
Vol 39 (4) ◽  
pp. 831-833 ◽  
Author(s):  
M. V. Muftakhov ◽  
V. A. Mazunov ◽  
V. I. Khvostenko
Keyword(s):  
Electron Capture ◽  
Low Energy ◽  
Resonance States ◽  
Energy Resonance

Isomerization of the Isoprene Hydroxy Nitrates and Formation of Orthonitrite Compounds

2019 ◽  
Author(s):  
Gabriel da Silva
Keyword(s):  
Hydroxy Group ◽  
Peroxyl Radical ◽  
Branching Fractions ◽  
Membered Ring ◽  
Low Energy ◽  
Peroxyl Radicals ◽  
Aerosol Formation ◽  
Subsequent Removal ◽  
Ring Compounds ◽  
Group Migration

Atmospheric oxidation of isoprene produces significant yields of eight unique nitrate 11 compounds, each with a β- or δ-hydroxy group. These isoprene hydroxy nitrates (ISOPNs) 12 significantly impact upon global NOx budgets, O3 levels, and aerosol formation. 13 Uncertainties exist, however, in our understanding of ISOPN chemistry, particularly in their 14 yields from the reaction of isoprene peroxyl radicals with NO. This study describes novel 15 isomerization reactions of the ISOPNs, identified through the application of computational 16 chemistry techniques. These reactions produce saturated polycyclic orthonitrite compounds 17 via attack of the R–NO2 group on the vinyl moiety. For the δ-hydroxy nitrates, low-energy 18 isomerization pathways exist to six-membered ring compounds that are around 5 kcal mol-1 19 exothermic. These reactions proceed with barriers around 15 kcal mol-1 below the 20 respective peroxyl radical + NO reactants and yield orthonitrites that can further isomerize 21 to β-hydroxy ISOPNs. Moreover, the δ-hydroxy nitrates can directly interconvert with their β 22 substituted counterparts via NO3 group migration, with barriers that are lower yet. It follows 23 that β-hydroxy nitrates may be stabilized in the δ-hydroxy form, and vice versa. Moreover, 24 the lowest-energy pathway for dissociation of the δ-hydroxy ISOPNs is for the formation of 25 β-hydroxy alkoxyl radicals, and because of this established branching fractions between the 26 various isoprene peroxyl radicals may require re-evaluation. The results presented here also 27 suggest that ISOPNs may be stabilized to some extent in their saturated orthonitrite forms, 28 which has implications for both the total nitrate yield and for their subsequent removal by 29 OH, O3, and photolysis.<br><br>

Fragmentations des cétones aliphatiques métastables. II. Compétition entre éliminations de radicaux hydrocarbonés et d'alcanes.

1982 ◽  
Vol 60 (16) ◽  
pp. 2107-2112 ◽  
Author(s):  
Guy Bouchoux ◽  
Yannik Hoppilliard
Keyword(s):  
Molecular Ions ◽  
Low Energy ◽  
Final States ◽  
Energy Channel ◽  
Aliphatic Ketones ◽  
Thermochemical Stability

The fragmentation of the metas table molecular ions of six aliphatic ketones is studied. The ion fragment abundances [M – R•] and [M–RH] (R• being a lateral radical) can be predicted from the thermochemical stability of the corresponding final states. Exceptions to this behavior are found for metastable molecular ions of methylethylketone and methylisopropylketone where it is demonstrated that the lifetime of these ions is too short to permit significant decompositions via the low energy channel after 10−5 s.

Fixed-angle method for low-energy resonance calculations

1965 ◽  
Vol 38 (2) ◽  
pp. 872-882 ◽  
Author(s):  
H. Burkhardt ◽  
G. P. McCauley
Keyword(s):  
Low Energy ◽  
Fixed Angle ◽  
Energy Resonance ◽  
Angle Method

scholarly journals Direct measurements of low-energy resonance strengths of the 23Na(p,γ)24Mg reaction for astrophysics

2019 ◽  
Vol 795 ◽  
pp. 122-128 ◽  
Author(s):  
A. Boeltzig ◽  
A. Best ◽  
F.R. Pantaleo ◽  
G. Imbriani ◽  
M. Junker ◽  
...  
Keyword(s):  
Low Energy ◽  
Energy Resonance ◽  
Direct Measurements ◽  
Resonance Strengths

scholarly journals Low-energy collisions with atomic and molecular ions in a photocathode electron target

2009 ◽  
Vol 194 (1) ◽  
pp. 012024 ◽  
Author(s):  
A Wolf ◽  
D A Orlov ◽  
C Krantz ◽  
M Lestinsky ◽  
A Shornikov ◽  
...  
Keyword(s):  
Molecular Ions ◽  
Low Energy ◽  
Electron Target

Nonlinear Parametric Vibration of the Geometrically Imperfect Pipe Conveying Pulsating Fluid

2020 ◽  
Vol 12 (06) ◽  
pp. 2050064
Author(s):  
Qian Li ◽  
Wei Liu ◽  
Kuan Lu ◽  
Zhufeng Yue
Keyword(s):  
Flow Velocity ◽  
Pitchfork Bifurcation ◽  
High Energy ◽  
Low Energy ◽  
Pulsation Frequency ◽  
Chaotic Motions ◽  
Integration Algorithm ◽  
Dynamic Behaviors ◽  
Geometric Imperfection ◽  
Energy Resonance

In this paper, the novel model of fluid-conveying imperfect pipe supported at both ends is established by considering the geometric imperfection and the geometric nonlinearity induced by mid-plane stretching. The integral-partial differential equation is discretized by the Galerkin method and solved by a fourth-order Runge–Kutta integration algorithm. Compared with the supercritical pitchfork bifurcation of the perfect pipe conveying fluid, the results show that the cusp bifurcation occurs in the imperfect pipe when increasing the flow velocity. Excellent agreement is observed between the numerical results and the analytical results. The two stable asymmetry bifurcation branches bring interesting phenomena in the post-buckling state. The global nonlinear dynamic behaviors of the imperfect pipe are studied by establishing the bifurcation diagrams. The influence of the geometric imperfection amplitude on the nonlinear response is leading to cusp bifurcation comparing with pitchfork bifurcation of the perfect pipe. When pulsation frequency is set as the bifurcation parameter, there are clear nonresonance ranges, low energy resonance ranges and high energy resonance ranges. In the high energy resonance ranges, the first mode vibration coexisting with the sub-harmonic resonance and combination resonance occurs. As the mean flow velocity and pulsation amplitude are set as bifurcation parameters, the vibration of the imperfect pipe becomes more and more complicated. The vibration exhibits far richer dynamic behaviors including periodic, multi-periodic, quasi-periodic, and chaotic motions. The viscoelastic damping can effectively suppress the vibration response and transfer the high energy resonance to the low energy resonance state. The improved model and corresponding results provide useful information for further studying the dynamic behaviors of fluid-conveying pipe with geometric imperfections.

On the Possibility of a Nuclear Mass-Energy Resonance in D + D Reactions at Low Energy

1989 ◽  
Vol 16 (2) ◽  
pp. 237-239 ◽  
Author(s):  
J. Rand McNally
Keyword(s):  
Low Energy ◽  
Mass Energy ◽  
Nuclear Mass ◽  
Energy Resonance
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