Quantification of the Free Radical Content of Oilsands Bitumen Fractions
Bibliographic record
Abstract
Electron spin resonance (ESR) spectroscopy was employed to perform quantitative analysis of the free radical content of oilsands bitumen, asphaltenes, deasphalted oil, vacuum residue, and vacuum gas oil fractions, as well as thermally converted product fractions. Calibration standards for ESR were compared, and 2,2-diphenyl-1-picrylhydrazyl was selected. The heaviest fractions, including asphaltenes, had free radical concentrations in the range 1017–1018 spins/g, whereas lighter fractions such as the lighter gas oil fractions had free radical concentrations in the range 1016–1017 spins/g. It was found that the bulk liquid properties affected the measured free radical concentration even after compensating for effects that could affect the spectroscopy. These differences were not analytical artifacts and could be explained with reference to the literature in terms of the “equilibrium” composition resulting from dimerization and decomposition of free radical pairs. Reported free radical concentrations must consequently be interpreted by considering the nature of the bulk liquid that was analyzed. Practically, the results have implications for thermal conversion of bitumen. It appears that the free radical concentration and availability of reactive free radicals can be independently manipulated through temperature and the bulk liquid properties.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 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 teacher head, 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".