Influence of the Chemical Composition on the Phase Constitution and the Elastic Properties of RF‐Sputtered Hydroxyapatite Coatings
Bibliographic record
Abstract
Abstract We have studied the influence of chemical composition on the constitution and elastic properties of dense radio‐frequency (RF)‐sputtered hydroxyapatite (HA) coatings. The chemical composition was modified by varying the RF sputtering power density (PD). As the PD was increased by 240%, the Ca/P ratio measured by X‐ray photoelectron spectroscopy increased from ≈1.51 to ≈1.82. X‐ray diffraction indicates phase pure hexagonal HA except for the sample prepared at the highest PD where CaO and Ca3(PO4)2 also form. Deviations from the stoichiometric Ca/P ratio result in reduction of the elastic modulus. For Ca/P = 1.51 ± 0.02, the elastic modulus decreases by ≈15%. This may be due to incorporation of Ca vacancies in the lattice, while for Ca/P = 1.82 ± 0.02, the average elastic modulus decreases by ≈10% due to formation of additional phases. magnified image
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 | 0.000 | 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 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".