A New Method of Gel-Coating Polyethyleneimine (PEI) on Organic Resin Beads. High Capacity and Fast Kinetics of PEI Gel-Coated on Polystyrene
Bibliographic record
Abstract
A new process has been developed for gel-coating a high-capacity weak-base resin, polyethyleneimine (PEI), on an inert organic support, polystyrene (PS), used as macroporous spherical beads. The process produces a thin and firm coating of PEI, cross-linked with glutaraldehyde and chemically bonded to the PS surface through carboxylic acid groups, created a priori by exposure to a chromic acid solution in glacial acetic acid for 3 h at the reflux temperature. Designated as OPS···[PEI.XG], the spherical gel-coated beads afford nearly full attainment of the theoretical proton capacity of the coated resin and exhibit significantly faster attainment of equilibrium sorption, compared to a conventional bead-form ion exchanger. Ascorbic acid and UO 2 SO 4 have been used as test sorbates for comparing the performance of OPS···[PEI.XG] with that of a commercial weak-base resin poly(4-vinylpyridine) (PVP). In an ascorbic acid substrate solution, the gel-coat layer of OPS···[PEI.XG] exhibits a sorption capacity of 12 mmol/g of (dry) resin, as compared to 2 mmol/g of (dry) PVP resin beads, while for UO 2 2+ the corresponding capacities are 4.5 and 1.1 mmol/g of dry resin, respectively. Large differences are also observed in sorption rates of gel-coated resin beads, in which the sorption is largely confined to the surface gel layer, and conventional resin beads, in which sorption occurs in the whole matrix.
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 | 0.001 | 0.001 |
| 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 | 0.000 |
| 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".