Probabilistic Models and Uncertainty Quantification for the Ionization Reaction Rate of Atomic Nitrogen

2011 ◽  
Author(s):  
Kenji Miki ◽  
M. Panesi ◽  
E. Prudencio ◽  
S. Prudhomme
Keyword(s):  
Uncertainty Quantification ◽  
Reaction Rate ◽  
Probabilistic Models ◽  
Atomic Nitrogen ◽  
Ionization Reaction

scholarly journals Effect of non-ionizing reaction rate (assumed to be controllable) on the plasma generation mechanism and communication around RAMC vehicle during atmospheric reentry

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wenchong Ouyang ◽  
Qi Liu ◽  
Zheng Zhang ◽  
Tao Jin ◽  
Zhengwei Wu
Keyword(s):  
Reaction Rate ◽  
Wave Attenuation ◽  
Plasma Sheath ◽  
Generation Mechanism ◽  
Transmission Model ◽  
Attenuation Effect ◽  
Plasma Generation ◽  
Atmospheric Reentry ◽  
Communication Signal ◽  
Ionization Reaction

AbstractRadio frequency (RF) blackout occurs during radio attenuation measurement C (RAMC) vehicle reentry due to the attenuation effect of the plasma sheath on the communication signal. In recent years, the mitigation mechanism of chemical reaction for RF blackout problem has gradually been studied numerically and experimentally. However, the effect of non-ionization reaction rate has been ignored because it does not directly involve the generation of electrons. In the present study, the influence of non-ionizing reaction rate on the plasma generation mechanism and EM wave attenuation was numerically solved by the plasma flow and multilayer transmission model. According to the simulation results, only the reaction rate of $$NO \rightleftharpoons N + O$$ N O ⇌ N + O has a significant effect on the electron number density in all non-ionizing reactions, and the degree of influence is less than the ionization reaction rate. The EM wave attenuation decreases with the decrease of the reaction rate of $$NO \rightleftharpoons N + O$$ N O ⇌ N + O . When the reaction rate is reduced by 25 times, the maximum attenuation of electromagnetic wave can be reduced by 12 dB. Finally, a potential scheme by reducing the reaction rate of $$NO \rightleftharpoons N + O$$ N O ⇌ N + O was proposed to mitigate the RF blackout problem.

Estimation of the nitrogen ionization reaction rate using electric arc shock tube data and Bayesian model analysis

2012 ◽  
Vol 19 (2) ◽  
pp. 023507 ◽  
Author(s):  
K. Miki ◽  
M. Panesi ◽  
E. E. Prudencio ◽  
S. Prudhomme
Keyword(s):  
Shock Tube ◽  
Bayesian Model ◽  
Reaction Rate ◽  
Model Analysis ◽  
Electric Arc ◽  
Ionization Reaction

scholarly journals Bayesian inversion for imprecise probabilistic models using a novel entropy-based uncertainty quantification metric

2022 ◽  
Vol 162 ◽  
pp. 107954
Author(s):  
Lechang Yang ◽  
Sifeng Bi ◽  
Matthias G.R. Faes ◽  
Matteo Broggi ◽  
Michael Beer
Keyword(s):  
Uncertainty Quantification ◽  
Probabilistic Models ◽  
Bayesian Inversion

Locating Al in the DABCO catalyst before and after Al extraction

1990 ◽  
Vol 48 (4) ◽  
pp. 265-267
Author(s):  
Kathleen B. Reuter
Keyword(s):  
Active Site ◽  
Inverse Relationship ◽  
Transverse Direction ◽  
Reaction Rate ◽  
Acid Phosphate ◽  
Fracture Surfaces ◽  
Al Content ◽  
Before And After ◽  
Relationship Of

The reaction rate and efficiency of piperazine to 1,4-diazabicyclo-octane (DABCO) depends on the Si/Al ratio of the MFI topology catalysts. The Al was shown to be the active site, however, in the Si/Al range of 30-200 the reaction rate increases as the Si/Al ratio increases. The objective of this work was to determine the location and concentration of Al to explain this inverse relationship of Al content with reaction rate.Two silicalite catalysts in the form of 1/16 inch SiO2/Al2O3 bonded extrudates were examined: catalyst A with a Si/Al of 83; and catalyst B, the acid/phosphate Al extracted form of catalyst A, with a Si/Al of 175. Five extrudates from each catalyst were fractured in the transverse direction and particles were obtained from the fracture surfaces near the center of the extrudate diameter. Particles were also obtained from the outside surfaces of five extrudates.

Direct observation of Fe-Al-Zn ternary intermetallic compound and its transformation during the early stage of hot-dip galvanizing

1993 ◽  
Vol 51 ◽  
pp. 1116-1117
Author(s):  
C. S. Lin ◽  
W. A. Chiou ◽  
M. Meshii
Keyword(s):  
Intermetallic Compound ◽  
Reaction Rate ◽  
Diffusion Rate ◽  
Early Stage ◽  
Zinc Bath ◽  
Steel Sheets ◽  
Direct Observations ◽  
Solid Iron ◽  
Iron And Zinc ◽  
Ternary Intermetallic Compound

The galvannealed steel sheets have received ever increased attention because of their excellent post-painting corrosion resistance and good weldability. However, its powdering and flaking tendency during press forming processes strongly impairs its performance. In order to optimize the properties of galvanneal coatings, it is critical to control the reaction rate between solid iron and molten zinc.In commercial galvannealing line, aluminum is added to zinc bath to retard the diffusion rate between iron and zinc by the formation of a thin layer of Al intermetallic compound on the surface of steel at initial hot-dip galvanizing. However, the form of this compound and its transformation are still speculated. In this paper, we report the direct observations of this compound and its transformation.The specimens were prepared in a hot-dip simulator in which the steel was galvanized in the zinc bath containing 0.14 wt% of Al at a temperature of 480 °C for 5 seconds and was quenched by liquid nitrogen.

Sign in / Sign up

Export Citation Format

Share Document