| Acronym | Meaning |
| CASS | Cyclic Activated Sludge System |
| PASPE | Photochemically Accumulated Stimulated Photon Echo |
| UNO | Unrestricted Natural Orbital |
| VA-LUMO | Vibrationally Active LUMO |
| EBEBO | Extended Bond Energy Bond Order (quantum Calcn. Method) |
| LSD | Lysergic Acid Diethylamide |
| CBXT | Community-Based Clinical Trial |
| MPE | Mean Percent Error |
| ASMD | Atmospheric Sciences Modeling Division (US EPA) |
| GPUCHF | Geometric Perturbed Uncoupled Hartree-Fock Method |