Utility of ammonium salts for the calibration of NH<sub>3</sub> sensors
Bibliographic record
Abstract
Abstract The calibration of NH 3 -sensing instruments has been an ongoing challenge to atmospheric chemists. Here, the potential utility of ammonium nitrate (NH 4 NO 3 ), -sulfate ((NH 4 ) 2 SO 4 ), -bisulfate (NH 4 HSO 4 ), -carbonate ((NH 4 ) 2 CO 3 ), and -bicarbonate (NH 4 HCO 3 ) to generate gas streams containing NH 3 or aerosol NH 4 + calibrated by measuring the co-emitted acids was investigated. Head space vapors and aerosols were analyzed using a commercial total nitrogen (N t ) instrument modified to quantify N t mixing ratios in both the gas- and particle phases, scanning mobility particle sizing, thermal-dissociation cavity ring-down spectroscopy, and Fourier transform infrared spectroscopy. The best results were obtained with NH 4 HCO 3 . Using a simple gas delivery setup consisting of two dilution stages and a line heater, the NH 3 output from NH 4 HCO 3 was calibrated by quantifying the stoichiometric co-emission of CO 2 with a relatively inexpensive non-dispersive infrared spectrometer. The new approach constitutes a viable alternative to conventional NH 3 cylinder calibration setups.
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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 | 0.000 | 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 | 0.001 |
| 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 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".