Transient species produced in the photochemical decomposition of ceric salts in aqueous solution. Reactivity of nitrogen oxide and hydrogen compd. with oxygen and sulfur (HSO4) free radicals

1967 ◽  
Vol 71 (12) ◽  
pp. 3802-3808 ◽  
Author(s):  
Libera Dogliotti ◽  
Elie Hayon
Keyword(s):  
Aqueous Solution ◽  
Free Radicals ◽  
Nitrogen Oxide ◽  
Transient Species ◽  
Photochemical Decomposition

Formation of α-Keto Acids from α-Amino Acids by the Action of Free Radicals in Aqueous Solution

Science ◽  
1951 ◽  
Vol 114 (2964) ◽  
pp. 412-413
Author(s):  
G. R. A. Johnson ◽  
George Scholes ◽  
Joseph Weiss
Keyword(s):  
Aqueous Solution ◽  
Amino Acids ◽  
Free Radicals ◽  
Keto Acids

Article

1998 ◽  
Vol 76 (7) ◽  
pp. 1064-1069 ◽  
Author(s):  
X -Z Zhang ◽  
R C Francis ◽  
D B Dutton ◽  
R T Hill
Keyword(s):  
Aqueous Solution ◽  
Free Radicals ◽  
Free Radical ◽  
Peracetic Acid ◽  
Kinetic Data ◽  
Radical Scavenging ◽  
Similar Type ◽  
Pulp Fibers ◽  
Radical Decomposition ◽  
Wood Pulps

Peracetic acid (Pa) is now being used for totally chlorine-free delignification and bleaching of wood pulps. During the process, metals desorb from the pulp fibers into the aqueous solution. Of the relevant metals in bleaching systems, cobalt(II) and vanadium(V) are the most potent in wastefully decomposing Pa to O2. In the present study, radical scavenging by N,N'-(5-nitro-1,3-phenylene)-bisglutaramide (GAMID) indicates that free-radical mechanisms are operative. Kinetic data support a free-radical decomposition mechanism previously described for Co(II). A similar type of mechanism, involving VO(OH)2(aq) and VO(OH)3(aq), is postulated to partially explain catalysis by vanadium.Key words: peracetic acid, peroxymonosulfuric acid, transition metals, free radicals, acetoxy radical, peracetoxy radical.

A simulation of free radicals induced oxidation of dopamine in aqueous solution

2019 ◽  
Vol 524 ◽  
pp. 26-30 ◽  
Author(s):  
Branislav Milovanović ◽  
Jelica Ilić ◽  
Ivana M. Stanković ◽  
Milana Popara ◽  
Milena Petković ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Free Radicals

Ionizing Irradiation Property of L(+)-Alpha-Phenylglycine in Acid Aqueous Solution

2011 ◽  
Vol 343-344 ◽  
pp. 469-475
Author(s):  
Wen Yan Shi ◽  
Jian Zhong Gu ◽  
Zheng Jiao ◽  
Wen Jing Wu ◽  
Gang Xu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Steady State ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Laser Flash ◽  
Transient Species ◽  
Ionizing Irradiation ◽  
Steady State Analysis ◽  
Applied Dose ◽  
Acid Aqueous Solution

(+)-alpha-phenylglycine are significant contaminants at pharmaceutical intermediates production. To study processes for the destruction of contaminant L(+)-alpha-phenylglycine in acid aqueous solution we have investigated the transient species using both laser flash photolysis. The OH· reaction with L(+)-alpha-phenylglycine process was investigated and formed polymer. Furthermore, the results of steady-state analysis suggested that L(+)-alpha-phenylglycine removal was found to be more efficient with increasing applied dose. L(+)-alpha-phenylglycine, decreased by 44.50%, using a dose of 14kGy.

Photochemical decomposition of 2,4-dichlorophenoxy acetic acid (2,4-D) in aqueous solution. I. Kinetic study

1997 ◽  
Vol 35 (4) ◽  
pp. 31-39 ◽  
Author(s):  
María I. Cabrera ◽  
Carlos A. Martín ◽  
Orlando M. Alfano ◽  
Alberto E. Cassano
Keyword(s):  
Aqueous Solution ◽  
Radiation Effects ◽  
Batch Reactor ◽  
Dichlorophenoxyacetic Acid ◽  
Intrinsic Kinetics ◽  
Photochemical Decomposition ◽  
Kinetic Expression ◽  
2,4 Dichlorophenoxyacetic Acid ◽  
Dichlorophenoxy Acetic Acid ◽  
Kinetics Of

The intrinsic kinetics of the photochemical decomposition of 2,4-dichlorophenoxyacetic acid in aqueous solution has been studied using light of 253.7 nm. Experiments were carried out in a well stirred batch reactor irradiated from its bottom by means of a tubular lamp and a parabolic reflector. Results were analyzed in terms of a very simple kinetic expression. Absorbed radiation effects were duly quantified by means of a one-dimensional radiation field model. This approach incorporates a variable absorption coefficient that is a function of the 2,4-D conversion. The decomposition kinetics can be properly represented with a point valued equation of the following form: RD, λ = − ΦD,λ eλ(y).

Transient Species in the Pulse Radiolysis of Periodate Ion in Neutral Aqueous solution

1971 ◽  
Vol 75 (7) ◽  
pp. 626-626
Author(s):  
F. Barat ◽  
L. Gilles ◽  
B. Hickel ◽  
B. Lesigne
Keyword(s):  
Aqueous Solution ◽  
Pulse Radiolysis ◽  
Transient Species ◽  
Neutral Aqueous Solution

γ-Radiolysis of disulfides in aqueous solution. III. L-Cysteine-D-penicillamine mixed disulfide

1969 ◽  
Vol 47 (6) ◽  
pp. 1037-1043 ◽  
Author(s):  
J. W. Purdie
Keyword(s):  
Aqueous Solution ◽  
Free Radicals ◽  
Aqueous Solutions ◽  
Dose Rate ◽  
Sulfonic Acids ◽  
Rate Dependent ◽  
Mixed Disulfide ◽  
Γ Rays ◽  
Symmetrical Disulfides ◽  
Symmetrical Disulfide

L-Cysteine-D-penicillamine mixed disulfide (CySSPen) was irradiated in aerated and deaerated aqueous solutions with 60Co γ-rays. G values were determined for all products identified after exposure to 10 000 rads. The major products were the sulfinic and sulfonic acids (CySO2H, CySO3H, and PenSO2H), the sulfhydryl derivatives (CySH and PenSH), symmetrical disulfides (CySSCy and PenSSPen), three trisulfides (CySSSCy, CySSSPen, and PenSSSPen), and ammonia. Each half of the disulfide behaved in exactly the same way as the corresponding symmetrical disulfide. Products from the CyS— part of the disulfide were dose rate dependent while products from the PenS— part were independent of dose rate. The reactions proposed for the symmetrical disulfides were adequate to explain radiolysis of the unsymmetrical disulfide.Radiolysis of a mixture of cystine and penicillamine disulfide was examined for comparison with the unsymmetrical disulfide and was found to give very similar results. It was concluded that the free radicals produced from the water attack each half at approximately equal rates.

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