Microstructure and radiation tolerance of molybdenum-rich glass composite nuclear waste forms
Bibliographic record
Abstract
Non-active molybdenum-rich Ca/Zn glass composite materials (GCM) were prepared on the Vitrification Test Rig (VTR) in the UK. The GCM samples were subjected to Ni and Au ion irradiations to simulate the effects of alpha recoil damage and to determine how the crystallinity characteristics might affect the overall radiation tolerance of high-level wastes (HLW) generated during post-operational clean-out (POCO) operations at the Sellafield nuclear site. The typical crystal phases identified in the GCM were: powellite, ruthenium dioxide, zincochromite, zircon and cerianite. Gadolinium (a proxy for radioactive elements) accumulated mainly in powellite, zircon and cerianite crystals. Scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and grazing incidence X-ray diffraction (GIXRD) analyses showed that cerianite is a highly radiation-tolerant phase, whereas powellite and zircon became amorphous and swelled considerably after the Ni and Au ion irradiations. This research shows the first evidence of powellite amorphisation under heavy-ion irradiation and suggests that powellite is susceptible to amorphisation by alpha recoils in HLW materials, in contrast to previous findings. The evolution of cooling-related and irradiation-induced microcracks is also described. In HLW glass composite materials, the formation of microcracks is expected in the middle of the canister, where relatively large powellite and zircon crystals appear.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".