Influence of Coprecipitated Organic Matter on Fe<sup>2+</sup><sub>(aq)</sub>-Catalyzed Transformation of Ferrihydrite: Implications for Carbon Dynamics
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Aqueous Fe(II) is known to catalyze the abiotic transformation of ferrihydrite to more stable Fe minerals. However, little is known about the impacts of coprecipitated OM on Fe(II)-catalyzed ferrihydrite transformation and its consequences for C dynamics. Accordingly, we investigated the extent and pathway of Fe(II)-induced transformation of OM-ferrihydrite coprecipitates as a function of C/Fe ratios and aqueous Fe(II) concentrations, and its implications for subsequent C dynamics. The coprecipitated OM resulted in a linear decrease in ferrihydrite transformation with increasing C/Fe ratios. The secondary mineral profiles upon Fe(II) reaction with OM-ferrihydrite coprecipitates depend on Fe(II) concentrations At 0.2 mM Fe(II), OM completely inhibited goethite formation and stimulated lepidocrocite formation. At 2 mM Fe(II), whereas goethite was formed in the presence of OM, OM reduced the amount of goethite and magnetite formation and increased the formation of lepidocrocite. The solid-phase C content remained unchanged after reaction, suggesting that OM remains associated with Fe minerals following ferrihydrite transformation to more stable Fe minerals. However, C desorbability by H2PO4(-) from the resulting Fe minerals following reaction was enhanced. The study indicates a "lepidocrocite favoring effect" by OM and suggests that Fe(II)-catalyzed transformation of ferrihydrite may decrease OM stability in natural environments under moderately reducing conditions.
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.
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 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 it