Viscosity and physical state of sucrose mixed with ammonium sulfate droplets
Bibliographic record
Abstract
Although knowledge of the physical state of aerosol particles is essential to understand atmospheric chemistry model and measurements, information on the viscosity and physical state of aerosol particles consisting of organic and inorganic salts is still rare. Herein, we quantified viscosities at 293 ± 1 K upon dehydration for the binary systems, sucrose–H 2 O and ammonium sulfate (AS)–H 2 O, and the ternary systems, sucrose–AS–H 2 O for organic-to-inorganic dry mass ratios (OIRs) = 4:1, 1:1, and 1:4 using bead-mobility and poke-and-flow techniques. Based on the viscosity value of the aerosol particles, we defined the physical states of the total aerosol particles studied in this work. For binary systems, the viscosity of sucrose–H 2 O particles gradually increased from ∼ 4 × 10 −1 to > ∼ 1 × 10 8 Pa s when the relative humidity (RH) decreased from ∼ 81 % to ∼ 24 %, ranging from liquid to semisolid or solid state, which agrees with previous studies. The viscosity of AS–H 2 O particles remained in the liquid state (< 10 2 Pa s) for RH > ∼ 50 %, while for RH ≤∼ 50 %, the particles showed a viscosity of > ∼ 1 × 10 12 Pa s, corresponding to a solid state. In case of the ternary systems, the viscosity of organic-rich particles (OIR = 4:1) gradually increased from ∼ 1 × 10 −1 to ∼ 1 × 10 8 Pa s for a RH decrease from ∼ 81 % to ∼ 18 %, similar to the binary sucrose–H 2 O particles. This indicates that the sucrose–AS–H 2 O particles range from liquid to semisolid or solid across the RH. In the ternary particles for OIR = 1:1, the viscosities ranged from less than ∼ 1 × 10 2 for RH > 34 % to > ∼ 1 × 10 8 Pa s at ∼ 27 % RH. The viscosities correspond to liquid for RH > ∼ 34 %, semisolid for ∼ 34 % < RH < ∼ 27 %, and semisolid or solid for RH < ∼ 27 %. Compared to the organic-rich particles, in the inorganic-rich particles (OIR = 1:4), drastic enhancement in viscosity was observed as RH decreased; the viscosity increased by approximately 8 orders of magnitude during a decrease in RH from 43 % to 25 %, resulting in liquid to semisolid or solid in the RH range. Overall, all particles studied in this work were observed to exist as a liquid, semisolid, or solid depending on the RH. Furthermore, we compared the measured viscosities of ternary systems with OIRs of 4:1, 1:1, and 1:4 to the predicted viscosities using the Aerosol Inorganic–Organic Mixtures Functional groups Activity Coefficients Viscosity model (AIOMFAC-VISC) predictions with the Zdanovskii–Stokes–Robinson (ZSR) organic–inorganic mixing model, with excellent model–measurement agreement for all OIRs.
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".