| Acronym | Meaning |
| XRF | X-ray Fluorescence |
| STA | Single-transition Approximation |
| GEENET | Global Environmental Epidemiology Network |
| NLP | Natural Language Processing |
| PESIS | Photoelectron Spectroscopy Of The Inner Shell |
| NQCC | Nuclear Quadrupole Coupling Constants |
| HUG | HART User Group |
| JI | Joint Implementation [with Regard To Greenhouse Gas Emission Redn.] |
| SAB | Science Advisory Board (USEPA) |
| PWBA | Plane-Wave Born Approximation |