English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

In order to help understand the role of oxygen in Ce(IV)-induced oxidation of small carbonic acids, we investigated the reaction of glyoxylic acid (HCOCOOH) and Ce(IV) in 1 M sulfuric acid. Spectrophotometric data showed that in excess of glyoxylic acid the consumption of Ce(IV) obeys pseudo-first-order kinetics, with a rate constant of 8.8 L mol-1 s-1 at 25 °C and an activation energy of 80 kJ mol-1. Rapid-flow EPR measurements revealed an approximately 1:2:1 triplet with a g value of 2.0071 ± 0.0005 and a hyperfine splitting of 7.1 ± 0.2 G, assignable to the primary radical formed by abstraction of a hydrogen atom from hydrated glyoxylic acid. The rate constant for the anaerobic self-decay of the radical was measured as approximately 3.7 × 109 L mol-1 s-1. Surprisingly, oxygen had no effect on the Ce(IV) kinetics, while the radical decay was significantly inhibited under aerobic conditions (ratio of experimental rate constants ≈6.3). Amperometric measurements revealed accompanying oxygen consumption. An...

Oxidation of Glyoxylic Acid by Cerium(IV): Oxygen-Induced Enhancement of the Primary Radical Concentration