The Influence of Long-Term Gamma-Radiation and Initially Dissolved Chemicals on Aqueous Kinetics and Interfacial Processes
Notice bibliographique
Résumé
This thesis presents work focusing on the long-term effect of gamma-radiation on aqueous solution kinetics. Ionizing radiation drives the decomposition of water to form both oxidizing (•OH, O2, H2O2) and reducing (•eaq−, •O2−, •H, H2) chemical species. Over time, these radiolysis products can react with dissolved solutes and participate in interfacial reactions. This can lead to significant changes in the eventual solution redox condition, and gas phase composition, and in certain cases result in the formation of solid species. Understanding the long-term solution kinetics for radiolysis systems is particularly important for the improvement of chemistry control and activity transport models, such as those employed in the nuclear power industry.\nIn order to study the chemical changes induced by exposing these aqueous systems to gamma‑radiation, species in the aqueous, gaseous and solid phases (where applicable) were monitored by a variety of techniques as a function of irradiation time. Chemical kinetics modeling was performed to both validate obtained experimental results, as well as aid in the interpretation of these results. The presence of dissolved solutes was found to impact the steady-state concentrations of the molecular water radiolysis products by competing with them for reaction with radical species. This radical scavenging lowers the rate of removal of the molecular products and allows their concentrations to reach higher levels, however the increase observed relative to pure water is dependent on pH and solute concentration. Redox active solutes that can undergo pseudo-catalytic reaction cycles with the radical species can also significantly affect the concentrations of water radiolysis products without experiencing a significant change in their net speciation.\nIrradiation studies with transition metal solutes were shown to generate uniform sized colloidal species in solution. The radiolytic oxidation of soluble ferrous ions to less soluble ferric species leads to the homogeneous condensation of primary particles out of solution. Prolonged irradiation leads to growth at the particle surface, with the final size determined by the steady state balance of redox reactions occurring on the particle surface. Irradiation was also shown to increase the relative metal oxidation rate on a carbon steel coupon in aqueous solutions, with dissolution dominating over oxide growth at low pH. However, the initial presence of dissolved iron suppresses the metal oxidation rate. The deposition of radiolytically produced iron oxide/oxyhydroxide particles contributes to enhanced oxide film growth on these coupon surfaces, effectively decreasing the driving force for ongoing metal oxidation.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».