.gamma. Radiolysis of penicillamine in deaerated 1 M perchloric acid

Abstract

The products of radiolysis of penicillamine in 1 M HCIO4 are reported and their yields discussed. The reactions of • and -CH2OH are qualitatively similar to those observed for cysteine and produce primarily RS• radicals. However, the secondary reactions of RS• radicals give rise to a substantially higher yield of trisulfide (RSSSR) than is observed with cysteine. This appears to be due to the presence of weaker C-S bonds in the tertiary C-SH compound and to the fact that this bond can be broken as a result of interactions between RS• and RSH, possibly via the formation of a RSS(H)R intermediate. The magnitude of the rate constant ratio fe3(fc4 + ke)-1 at 1 ± 1 °C is 0.54 ± 0.10. At 23 6C it was found to be 0.50 ± 0.10 in good agreement with an earlier value of O.44.11

Rational Design of Local Reaction Environment for Electrocatalytic Conversion of CO2 into Multicarbon Products

“…For understanding the local pH effect, rotating ring‐disk electrode technique was applied, [30–34] owing to that this technique provides an effective method for the modulation of local pH gradient through varying the mass transport of anion species (such as OH − ) that is linked to the rotation speeds. Specifically, with increasing the rotation (mass transport) speeds, the locally generated hydroxyl ions are transported away from the electrode surface at an accelerated rate, [35] decreasing the local alkalinity. By comparing the catalytic performance of a polycrystalline Cu disk cathode with different rotation speeds, it was discovered that the electrocatalytic CO 2 R was suppressed upon increasing the rotation speeds, accompanying with an enhanced hydrogen evolution reaction [30] .…”