Isotherms, kinetics, and thermodynamics of methionine adsorption onto poorly crystalline hydroxyapatite with different Ca/P ratios
Bibliographic record
Abstract
The adsorption properties of hydroxyapatite of low crystallinity towards methionine have been examined. The chemical composition of hydroxyapatite was taken as an experimental variable in order to have a point of view on the parameters of the adsorption process and the mechanisms established between adsorbent-adsorbate. The adsorption kinetics are relatively fast, and the high amounts adsorbed at saturation are obtained for non-stoichiometric hydroxyapatite, containing more HPO42- ions and having a high specific surface area. The good agreement of the experimental data with kinetic models confirms that the mechanism can be perfectly described by pseudo-second-order kinetics. Adsorption isotherm models show that Langmuir's model gives a better fit of experimental data compared to that of Freundlich, Temkin and Dubinin-Kaganer-Radushkevich. Fourier transform infrared spectroscopy confirmed the interaction between the -COO- ions of methionine and the Ca2+ ions of hydroxyapatite. The thermodynamic parameters, the isoelectric point of methionine and the point of zero charge of hydroxyapatite with different Ca/P ratios show that the adsorption process is considered spontaneous, exothermic and often controlled by physisorption with interactions electrostatic.
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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) | 0.000 | 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 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".