Structurally Functionalized Polyurethane Foam for Elimination of Lead Ions from Drinking Water
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Polyurethane foams functionalized with Sulfonic acid groups have been found to be strong cation exchangers. This novel property of the foam was used to exchange lead (Pb2+) ions from aqueous solutions. Polyurethane foam synthesis is based on addition polymerization of the highly reactive isocyanate (-NCO) groups of an isocyanate with the hydroxyl (–OH) groups of a polyol to form the urethane species. Toluene-2,4-2,6- diisocyanate was reacted with Polypropylene glycol 1200 in 2:1 molar ratio to form a linear pre-polymer. The linear pre-polymer was further polymerized using a chain extender, N, N-bis (2-hydorxyethyl)-2-aminoethane-sulfonic acid (BES). BES also acts as a functional group to exchange Pb2+ ions. A set of experiments were designed to study various process parameters. The functionalized polyurethane foam was characterized by Fourier transform infrared spectroscopy, gel permeation chromatography, scanning electron microscopy, and energy dispersive x-ray spectroscopy. The Pb2+ ion exchange capacity was determined using an Inductively Coupled Plasma Mass Spectrometer. The maximum Pb2+ ion exchange capacity of the foam was found to be 47 parts per billion per gram (ppb/g) from a 100 parts per billion (ppb) Pb2+ solution over a period of 60 minutes. A multistage batch filtration process increased the Pb2+ ion removal to 50-54 ppb/3g of foam over a period of 90 minutes.
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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 | 0.003 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 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 it