Temperature dependence of muonium reaction rates in the gas phase

1981 ◽  
Vol 8 (4-6) ◽  
pp. 337-345 ◽  
Author(s):  
D. G. Fleming ◽  
D. M. Garner ◽  
R. J. Mikula
Keyword(s):  
Temperature Dependence ◽  
Gas Phase ◽  
Reaction Rates ◽  
Muonium Reaction

Temperature Dependence of the Gas Phase Reaction Rates of CF3O with Methane, Ethane, and Isobutane

1995 ◽  
Vol 99 (41) ◽  
pp. 15102-15107 ◽  
Author(s):  
C. Bourbon ◽  
C. Fittschen ◽  
J. P. Sawerysyn ◽  
P. Devolder
Keyword(s):  
Temperature Dependence ◽  
Gas Phase ◽  
Reaction Rates ◽  
Phase Reaction ◽  
Gas Phase Reaction

Temperature-dependence study of the gas-phase reactions of atmospheric Cl atoms with a series of aliphatic aldehydes

2006 ◽  
Vol 40 (21) ◽  
pp. 3845-3854 ◽  
Author(s):  
Carlos A. Cuevas ◽  
Alberto Notario ◽  
Ernesto Martínez ◽  
José Albaladejo
Keyword(s):  
Temperature Dependence ◽  
Gas Phase ◽  
Gas Phase Reactions ◽  
Aliphatic Aldehydes ◽  
Cl Atoms

Atmospheric DMSO Degradation in the Gas Phase:  Cl−DMSO Reaction. Temperature Dependence and Products

2002 ◽  
Vol 36 (6) ◽  
pp. 1226-1230 ◽  
Author(s):  
Ernesto Martínez ◽  
Alfonso Aranda ◽  
Yolanda Díaz de Mera ◽  
Diana Rodríguez ◽  
M. Reyes López ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Gas Phase ◽  
Reaction Temperature

scholarly journals Terpenes and their oxidation products in the French Landes forest: insights from Vocus PTR-TOF measurements

2020 ◽  
Vol 20 (4) ◽  
pp. 1941-1959 ◽  
Author(s):  
Haiyan Li ◽  
Matthieu Riva ◽  
Pekka Rantala ◽  
Liine Heikkinen ◽  
Kaspar Daellenbach ◽  
...  
Keyword(s):  
Gas Phase ◽  
Detection Efficiency ◽  
Ambient Air ◽  
Reaction Rates ◽  
Early Morning ◽  
Oxidation Products ◽  
Atmospheric Oxidation ◽  
Organic Nitrates ◽  
Reaction Products ◽  
Wide Range

Abstract. The capabilities of the recently developed Vocus proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF) are reported for the first time based on ambient measurements. With the deployment of the Vocus PTR-TOF, we present an overview of the observed gas-phase (oxygenated) molecules in the French Landes forest during summertime 2018 and gain insights into the atmospheric oxidation of terpenes, which are emitted in large quantities in the atmosphere and play important roles in secondary organic aerosol production. Due to the greatly improved detection efficiency compared to conventional PTR instruments, the Vocus PTR-TOF identifies a large number of gas-phase signals with elemental composition categories including CH, CHO, CHN, CHS, CHON, CHOS, and others. Multiple hydrocarbons are detected, with carbon numbers up to 20. Particularly, we report the first direct observations of low-volatility diterpenes in the ambient air. The diurnal cycle of diterpenes is similar to that of monoterpenes and sesquiterpenes but contrary to that of isoprene. Various types of terpene reaction products and intermediates are also characterized. Generally, the more oxidized products from terpene oxidations show a broad peak in the day due to the strong photochemical effects, while the less oxygenated products peak in the early morning and/or in the evening. To evaluate the importance of different formation pathways in terpene chemistry, the reaction rates of terpenes with main oxidants (i.e., hydroxyl radical, OH; ozone, O3; and nitrate radical, NO3) are calculated. For the less oxidized non-nitrate monoterpene oxidation products, their morning and evening peaks have contributions from both O3- and OH-initiated monoterpene oxidation. For the monoterpene-derived organic nitrates, oxidations by O3, OH, and NO3 radicals all contribute to their formation, with their relative roles varying considerably over the course of the day. Through a detailed analysis of terpene chemistry, this study demonstrates the capability of the Vocus PTR-TOF in the detection of a wide range of oxidized reaction products in ambient and remote conditions, which highlights its importance in investigating atmospheric oxidation processes.

SiC HTCVD Simulation Modified by Sublimation Etching

2006 ◽  
Vol 527-529 ◽  
pp. 107-110 ◽  
Author(s):  
Yasuo Kito ◽  
Emi Makino ◽  
Kei Ikeda ◽  
Masao Nagakubo ◽  
Shoichi Onda
Keyword(s):  
Gas Phase ◽  
Reaction Rates ◽  
Reaction Model ◽  
Inductive Heating ◽  
Present Calculation ◽  
Quasi Equilibrium ◽  
Phase Reaction ◽  
Vapor Pressures ◽  
Gas Phase Reaction ◽  
Sticking Coefficients

High temperature chemical vapor deposition (HTCVD) simulations of silicon carbide (SiC) were demonstrated with experimental results. A vertical cylindrical reactor was used in an RF inductive heating furnace and the temperature was more than 2200. SiH4 and C3H8 were used as source gases and H2 as carrier gas. A gas phase reaction model from the literature was used on the condition that the gas phase reaction is a quasi-equilibrium state. It was found that the major species were Si, Si2C, SiC2 and C2H2 in the gas phase reaction model as well as in the thermodynamic equilibrium calculation. Sublimation etching was considered in the surface reaction rates by modifying partial pressures of species with equilibrium vapor pressures. CFD-ACE+ and MALT2 software packages were used in the present calculation. The sticking coefficients were determined by fitting the calculated growth rates to the experimental ones. The simulated growth rate in a different reactor is in good agreement with the experimental value, using the same sticking coefficients. The present simulation could be useful to design a new reactor and to find optimum conditions.

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