Dispersions of pyrogenic alumina in pentylcyanobiphenyl studied by deuteron NMR
Bibliographic record
Abstract
Dispersions of hydrophilic (Aeroxide Alu C) and hydrophobic (Aeroxide Alu C 805) pyrogenic alumina (Al2O3) in liquid crystal 4;{'} -n-pentyl-4-cyanobiphenyl (5CB) were investigated with deuteron nuclear magnetic resonance. The disorder effects of Al2O3 particles on the orientational order of liquid-crystal media and on the field-induced director configuration were studied as a function of alumina density in samples prepared by zero-field cooling and in-field cooling procedures. The order parameters and their variation with alumina density suggest a stronger disordering effect from the nonpolar surface of Alu C 805 particles. For dispersions of hydrophobic Alu C 805 experiments involving in-field cooling from the isotropic phase indicate that the director of "disordered" domains can be aligned, though not perfectly, by the field-aided annealing process. But the same in-field cooling procedure has shown rather limited alignment effects for hydrophilic Alu C/5CB samples. The more robust network of hydrophilic gel possibly coupled with weak liquid-crystal-network interactions could be responsible for the observed behavior. Spectra recorded during in-field cooling and within the isotropic-nematic coexistence region reveal the augmentation of the disorder strength during the transition and illustrate the effect of field-aided annealing. The stability of the aligned states as revealed by deuteron NMR is described. The results are discussed in comparison with previous studies of aerosil dispersions in alkylcyanobiphenyl.
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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".