Journal ArticleDOI
Re-evaluation of the thiocyanate dosimeter for pulse radiolysis
George V. Buxton,Craig R. Stuart +1 more
TLDR
In this article, the super-Fricke dosimeter was used as a secondary standard for the thiocyanate dosimeter in O2-saturated water and the results were improved to 3.47 ± 0.06.Abstract:
The thiocyanate dosimeter (10–2 mol dm–3 SCN– in O2-saturated water) has been standardised against the super-Fricke dosimeter (10–2 mol dm–3 FeII in O2-saturated 0.4 mol dm–3 H2SO4) using the hexacyanoferrate(II) dosimeter [5 × 10–3 mol dm–3 Fe(CN)64– in O2-saturated water] as a secondary standard. On the basis that G(FeIII)= 1.67 × 10–6 mol J–1 and IµFeIII= 220.4 m2 mol–1 at 304 nm and 25 °C in the super-Fricke dosimeter, we obtain GIµ[Fe(CN)63–]=(3.47 ± 0.06)× 10–5 m2 J–1 at 420 nm and GIµ(SCN)2˙–=(2.59 ± 0.05)× 10–4 m2 J–1 at 475 nm. These values remain unchanged when the solutions are saturated with air instead of O2 and are doubled in N2O-saturated solution.read more
Citations
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Pulse radiolysis studies on reactions of hydroxyl radicals with selenocystine derivatives.
TL;DR: From studies of reactions of hydroxyl radicals with selenocystine and two of its analogues, it has been concluded that the electron-donating carboxylic acid group decreases the reduction potential and facilitates quantitative conversion ofHydroxyl radical adducts to radical cations, while the electron -withdrawing NH(3)(+) group not only increases the reductionpotential but also leads to fragmentation of the hydroxy radical adduction to selenyl radicals, which
Journal ArticleDOI
Free radical reactions of monochloramine and hydroxylamine in aqueous solution
TL;DR: In this paper, rate constants for NH2Cl in water were derived for the reaction with the hydrated electron, the hydroxyl radical and the hydrogen atom, and the corresponding values of (2.2±0.1)×107 and (3.6±1.5)×105 m−1 s−1 were found.
Journal ArticleDOI
Primary photophysical properties of moxifloxacin--a fluoroquinolone antibiotic.
TL;DR: The photophysical properties of the fluoroquinolone antibiotic moxifloxacin (MOX) were investigated in aqueous media and the cation radical of MOX is able to oxidize protein components tryptophan and tyrosine.
Journal ArticleDOI
Studies on oxidative radiolysis of ibuprofen in presence of potassium persulfate
TL;DR: In this article, the radiolysis of ibuprofen (IBP), a model pharmaceutical compound, was studied by gamma irradiation in an aqueous solution in the presence and absence of potassium persulfate (K 2 S 2 O 8 ).
Journal ArticleDOI
One-electron oxidation of β-amyloid peptide: sequence modulation of reactivity
TL;DR: This is the first experimental demonstration of the sensitivity of the one-electron reduction potential of methionine on neighboring groups and the first time that such a drastic effect of the primary sequence is observed in a small peptide.
References
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Journal ArticleDOI
Critical Review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals (⋅OH/⋅O− in Aqueous Solution
TL;DR: In this article, the rate constants for over 3500 reaction are tabulated, including reaction with molecules, ions and other radicals derived from inorganic and organic solutes, and the corresponding radical anions, ⋅O− and eaq−, have been critically pulse radiolysis, flash photolysis and other methods.
Journal Article
Critical review of rate condtants for reaction of hydrated electrons, hydrogen atoms and hydroxyl radicals in aqueous solution
Journal ArticleDOI
Yield for the scavenging of hydroxyl radicals in the radiolysis of nitrous oxide-saturated aqueous solutions
TL;DR: In this article, the thiocyanate dosimeter was calibrated against the Fricke system to obtain a value of 46,400 +-600 (molecules/100 eV) for the product of yield and extinction coefficient of (SCN)/sub 2/O-saturated solutions.
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Track effects in radiation chemistry. Concentration dependence for the scavenging of hydroxyl by ferrocyanide in nitrous oxide-saturated aqueous solutions
TL;DR: In this paper, the radiation chemical yield for oxidation of ferrocyanide by OH produced in the fast electron radiolysis of N/sub 2/O-saturated aqueous solutions was found to increase from a low concentration limiting yield of 5.2 to values in excess of 6.7.