Gamma rays, or rather gamma radiation are most commonly used.
Based on the incomplete neutralization reaction above, the corresponding salts that each reaction would form are as follows:
1. H2SO4 + 2NH4OH----(NH4)2SO4 with water as a byproduct
2. 2NaOH + H2CO3 ----Na2CO3 with water as a byproduct
3. HNO3 + KOH ----KNO3 with water as a byproduct