High Temperature Simulated Distillation of Bitumen Fractions with Open Tubular Capillary Columns Depleted in Silicone/Siloxane Stationary Phases
Bibliographic record
Abstract
High Temperature Simulated Distillation (HTSD) is routinely carried out in petroleum laboratories for characterization of heavy hydrocarbon fractions. However, thermal cracking from HTSD high operating temperatures (up to 430 °C) has been reported to affect analytes during the chromatographic process. This work showed the feasibility of using silicone/siloxane depleted stationary phase wide bore capillary columns for HTSD carried out under lower setup temperatures to avoid cracking. Sequential low temperature elution for analysis followed by high temperature oven cycles for injector cleaning were found mandatory for successful operation. Depleted stationary phase metal capillary columns were determined as a feasible interesting alternative, advantageous from the point of view of column life span and retention times constancy. Present findings suggest that these columns can have useful life in the greater than or equal to a year span. Heavy hydrocarbon upgrading monitoring with standard and depleted stationary phase metal columns was found equivalent, further supporting the feasibility of using the latter for routine applications. X-ray photoelectron spectroscopy (XPS) analysis of the internal wall of metal columns highlighted differences brought by stationary phase depletion, particularly on the silicone/siloxane groups. Finally, preliminary results indicated that one further alternative to avoid “on column” thermal cracking is to elute standard columns to temperature limits <370 °C.
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) | 0.001 | 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 | 0.001 |
| 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".