| Acronym | Meaning |
| CBOA | Crude Born-Oppenheimer Approximation |
| UDWBA | Unitarized Disorted Wave Born Approxn. (for Scattering) |
| GS | Gelius-Siegbahn (MO Approxn.) |
| GFFF | Gravitational Field-flow Fractionation |
| ILM | Immobilized Liquid Membrane |
| PCP | Photoelectric Charging Of Particles |
| XNBR | Carboxylated Nitrile Rubber |
| ISCA | Ionization Spectroscopy For Chemical Analysis |
| UHE | Ultra-high Energy |
| ASMD | Atmospheric Sciences Modeling Division (US EPA) |