Reactions of Free Radicals with Olefins. Thermal Decomposition of t-Butyl Peracetate in the Presence of 4-Vinylcyclohexene

1964 ◽  
Vol 29 (2) ◽  
pp. 482-485 ◽  
Author(s):  
J. Reid Shelton ◽  
Hans-Georg Gilde
Keyword(s):  
Thermal Decomposition ◽  
Free Radicals

Effects of phenolic compounds from blueberry leaves on the thermal decomposition of trimethylamine oxide in squid extract

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Yingchang Li ◽  
Fengxia Du ◽  
Suzhen Song ◽  
Shuangyan Li ◽  
Xianqing Yang ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Free Radicals ◽  
Chlorogenic Acid ◽  
Theoretical Basis ◽  
Leaf Extract ◽  
Aquatic Products ◽  
Trimethylamine Oxide ◽  
Mechanism Of Inhibition ◽  
Development And Utilization ◽  
Blueberry Leaves

AbstractThe effects of chlorogenic acid and quercetin-3-D-galactoside on the decomposition of trimethylamine oxide (TMAO) in squid extract and the main mechanism of inhibition of thermal decomposition were studied. The results indicated that chlorogenic acid and quercetin-3-D-galactoside could inhibit decomposition of TMAO in squid extract. The amount of TMAO was increased by 11.79 and 15.76% in squid extract treated with chlorogenic acid and quercetin-3-D-galactoside from 0 and 2.5 g/L, respectively. The contents of trimethylamine (TMA), dimethylamine (DMA), and formaldehyde (FA) were significantly decreased with increasing contents of chlorogenic acid and quercetin-3-D-galactoside. There were many free radicals in squid extract at high temperatures; however, the free radical signals were weakened after the addition of chlorogenic acid and quercetin-3-D-galactoside therein. This implied that chlorogenic acid and quercetin-3-D-galactoside could inhibit the thermal decomposition of TMAO in squid extract, which was associated with the scavenging of their free radicals. This result provides a theoretical basis for the development and utilization of blueberry leaf extract as an efficient FA inhibitor for aquatic products.

FREE RADICALS BY MASS SPECTROMETRY: VII. THE IONIZATION POTENTIALS OF ETHYL, ISOPROPYL, AND PROPARGYL RADICALS AND THE APPEARANCE POTENTIALS OF THE RADICAL IONS IN SOME DERIVATIVES

1955 ◽  
Vol 33 (5) ◽  
pp. 861-869 ◽  
Author(s):  
J. B. Farmer ◽  
F. P. Lossing
Keyword(s):  
Mass Spectrometry ◽  
Thermal Decomposition ◽  
Free Radicals ◽  
Kinetic Energy ◽  
Electron Impact ◽  
Ionization Potentials ◽  
Bond Dissociation Energies ◽  
Radical Ions ◽  
Dissociation Energies ◽  
Propargyl Radicals

The ionization potentials of ethyl, isopropyl, and propargyl radicals have been measured by electron impact on radicals produced by thermal decomposition of appropriate compounds. The values are:ethyl 8.78±0.05 ev., isopropyl 7.90±0.05 ev., and propargyl 8.25±0.08 ev. From the appearance potentials of these ions in various compounds, the following values of bond dissociation energies were obtained:[Formula: see text][Formula: see text] assuming no kinetic energy of the products.

FREE RADICALS BY MASS SPECTROMETRY: XXXII. THERMAL DECOMPOSITION OF CYCLOPENTYL RADICALS

1965 ◽  
Vol 43 (3) ◽  
pp. 565-569 ◽  
Author(s):  
T. F. Palmer ◽  
F. P. Lossing
Keyword(s):  
Mass Spectrometry ◽  
Thermal Decomposition ◽  
Free Radicals ◽  
Elevated Temperatures ◽  
Bond Rupture ◽  
Low Pressures

At low pressures and elevated temperatures cyclopentyl radicals are found to dissociate mainly by two modes of reaction: about 34% by loss of H atom to form cyclopentene, and about 66% by a C—C bond rupture to form ethylene and allyl radicals. Under the conditions employed no evidence for a third possible mode, the loss of H2 to form cyclopentenyl radical, could be found. It is estimated that an incidence of 2% of the latter could have been detected.

Pyrolysis of Trifluoroacetaldehyde

1973 ◽  
Vol 51 (14) ◽  
pp. 2292-2296 ◽  
Author(s):  
Michael T. H. Liu ◽  
Leon F. Loucks ◽  
Robert C. Michaelson
Keyword(s):  
Thermal Decomposition ◽  
High Pressure ◽  
Free Radicals ◽  
Rate Equation ◽  
Pressure Dependence ◽  
Inert Gas ◽  
Order Process ◽  
First Order ◽  
Pressure Region ◽  
High Pressure Region

The thermal decomposition of trifluoroacetaldehyde has been studied over the 460–520 °C temperature range, and at pressures from 4 to 400 mm Hg. The experimental rate equation in the high-pressure region is of the form: Rate = k[CF3CHO]3/2 where[Formula: see text]The results are consistent with a mechanism initiated by a first order process and terminated by a second order recombination of two CF3 free radicals. At lower pressures (40 mm Hg), the ratio of kinit/kterm is pressure dependent and the overall order increases. The effects of added inert gas confirm this pressure dependence.

Sign in / Sign up

Export Citation Format

Share Document