Bibliographic record
Abstract
The fouling characteristics of artificially hardened waters containing calcium and orthophosphate ions were investigated. The water was circulated through a steam heated double pipe heat exchanger under turbulent flow conditions. Inlet water temperatures were about 20 to 25°C and the phosphate content about 100 ppm. Experiments were carried out to ascertain the effects of pH, velocity, surface temperature and concentrations of the calcium and the orthophosphate on the fouling process. The fouling behaviour was recorded in terms of the fouling resistance-time curve which was calculated from the time dependence of the overall heat transfer coefficients. Under the constant heat flux condition imposed, the fouling resistance was generally linear in time; however, asymptotic fouling was observed in some cases. The fouling rate was found to be a very strong function of the pH over the range 6.5 to 8.0. The rate was also found to be exponentially dependent on the calculated surface temperature. The initial fouling rate increased linearly with the velocity and with the concentrations of scale forming species. Deposit thickness increased with heated length of the stainless steel test section. In most cases, the deposit was a dense crystalline scale, which had a Ca/P molar ratio of 1.35±0.15. The results are discussed in terms of the ionic equilibrium involved and the solubility and crystallisation kinetics from the literature. It is apparent that the rate of phosphate precipitation is influenced both by surface reaction and mass transfer in the range of the variables studied. Findings are compared with the few prior phosphate fouling studies from the literature. Scale density is reported, and its thermal conductivity estimated using the fouling resistance measurements.
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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) | 0.001 | 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), 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".