| Acronym | Meaning |
| NDBEPR | Nitrification-denitrification Biological Excess Phosphorus Removal |
| VE-PPP | Variable Electronegativity PPP |
| FAB | Fast Atom Bombardment (mass Spectrometry) |
| DBD | Dielectric Barrier Discharge |
| PCI-X | Parametrized Configuration Interaction (with Parameter) X |
| OAW | Oxyacetylene Welding |
| NCEA | National Center For Environmental Assessment |
| IF | Interstitial Free |
| DIB | Diffuse Interstellar Band |
| HFPT | Hartree-Fock Perturbation Theory |