Sensitive Chemical Optic Sensor Using Birefringent Porous Glass for the Detection of Volatile Organic Compounds
Bibliographic record
Abstract
A simple design involving a birefringent porous glass oriented between two crossed polarizers serves as the foundation for an optically based sensitive broad-spectrum chemical sensor. Volatile organic compounds (VOCs) such as acetonitrile vapors can be readily detected at concentrations of as low as 50 ppm. Changes are observed in polarized light transmitted by the anisotropic porous material constituting the sensor, upon exposure to VOC-bearing air, as intensity changes at a defined wavelength or as changes in spectral content (color) detectable by the eye. The optical effects resulting from exposure to various vapors are reversible and may result from adsorption of solvent vapors with attendant reduction of anisotropy. The microporous structure as well as the surface chemistry of the sensor may be controlled for tuning the response to VOCs for industrial applications. Miniaturization of the sensor using low-cost materials such as plastic or glass optical fibers, Polaroid films, and birefringent porous glass is demonstrated. The sensor described in this paper could use ambient light as source and the eye as detector (color change) or electronically controlled light emission and detection for better sensitivity and real time monitoring of VOCs. Such intrinsic explosion proof sensors could be used to safely monitor VOC levels in remote environments.
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 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".