Biaxial deformation of a polymer under shear: NMR test of the Doi-Edwards model with convected constraint release
Bibliographic record
Abstract
2H NMR quadrupole interaction spectroscopy has been used to measure the deformation of a 670 kD poly(dimethylsiloxane) melt under shear in a Couette cell. The signals were acquired from a per deuterated benzene probe molecule which provides a motionally averaged sampling of the entire segmental ensemble. We have measured the dependence on shear rate of the S(XX) (velocity), S(YY) (velocity gradient), S(ZZ) (vorticity), and S(XY) (shear) elements of the segmental alignment tensor, as well as the angular dependence of the deuterium quadrupole splitting at fixed shear rate. We show that the data agree quite well with the Doi-Edwards theory but significantly better when convected constraint release effects are included. These fits return a value for the tube disengagement time of 100 ms.
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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) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".