Dielectric Properties of Ga-Doped Na<sub>0.5</sub>K<sub>0.5</sub>NbO<sub>3</sub>
Bibliographic record
Abstract
In this Article, we investigated the dielectric properties of B-site Ga-doped K 0.5 Na 0.5 NbO 3 (KNN) in air using AC impedance spectroscopy from room temperature to about 800 °C. Powder X-ray diffraction (PXRD) studies showed the formation of perovskite-type structure with orthorhombic symmetry, √2 a p × 4 a p × √2 a p (where a p is perovskite-type lattice constant) for x = 0.01, 0.1, and 0.13 members of Na 0.5 K 0.5 Nb 1− x Ga x O 3 . The PXRD result is similar to the parent KNN structure. AC impedance results showed mainly bulk contribution over the frequency range of 0.1 Hz to 1 MHz for the x = 0.01 member, while bulk and grain-boundary contributions were present for x > 0.01 in the same frequency range. Scanning electron microscopy was used to study the effect of microstructure change for Ga 3+ substitution in KNN. The inclusion of Ga 3+ in KNN showed a significant change in the microstructure. The dielectric properties of Na 0.5 K 0.5 Nb 1− x Ga x O 3 were enhanced by increasing the Ga 3+ content; among the compounds studied, the x = 0.1 member exhibited the highest dielectric constant and lowest dielectric loss at 1 MHz over the temperature range studied. All of the Na 0.5 K 0.5 Nb 1− x Ga x O 3 materials had a maximum dielectric constant at around 420 °C, which is consistent with other KNN ceramics reported in the literature and can be attributed to the Curie temperature. A small peak in the dielectric constant at around 220 °C was due to a structural phase transition.
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) | 0.000 | 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 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".