Impact of Corrosion Control on Biofilm Development in Simulated Partial Lead Service Line Replacements
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
Interaction of water quality, flow conditions, and the presence of lead and biofilm was examined in simulated partial lead service line replacement. Recirculating pipe loops were connected to individual 90-L reservoirs, and biofilm was collected from polycarbonate coupons. Three corrosion inhibitors, including sodium orthophosphate (OP) (1 mg-P/L), zinc orthophosphate (ZOP) (1 mg-P/L), or sodium silicate (10 mg/L), were used to treat Pb-Cu pipe loops. Controls included an “inhibitor-free,” “galvanic free,” and “lead-free” with Pb-Cu, Pb-PVC, and PVC-PVC coupled pipe loops, respectively. Adenosine triphosphate (ATP) was used to measure energy production of living cells and as a proxy to assess biofilm growth. The two highest (significant) ATP counts were found in the OP (under stagnant conditions) and ZOP (under flow-through conditions). Sodium silicates generally produced lower ATP counts compared to the phosphate-based inhibitors in the flow-through condition, although these differences were not statistically significant. Significant positive correlation between presence of lead and biofilm (ATP) and presence of copper and biofilm (ATP) were observed, although this observation does not imply a linear relationship. Biofilm was observed to act as a significant reservoir for lead with values ranging from 0.06 to 0.81 μg Pb/cm2 before chlorination to 0.04 to 0.21 μg Pb/cm2 postchlorination. This work highlights the potential for biofilm to act as a reservoir and subsequently as a source of lead release, and underscores the value of including biofilm evaluation when selecting corrosion inhibitors.
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.
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 it