Relative abundances of sulphur-bearing species (main isotopologue) with H₂ (top). The N_CS and N_SO are calculated from , and ³²S∕³⁴S = (3.3 ± 0.5) (DGC/kpc) + 4.1 ± 3.1(~ 32 ± 5 for our cores), adopted from Chin et al. (1996). For the undetected species, we estimated the upper limit of their column densities based on the integrated area upper limit given in Table A.2. The sulphur-bearing species abundances are adopted from Lattanzi et al. (2020), Vastel et al. (2018b), and Gratier et al. (2016) for L183, L1544, and TMC-1 CP, respectively. The average N(H₂) of L183 and L1544 are (10.0 ± 1.7) × 10²² cm⁻² and (9.4 ± 1.6) × 10²² cm⁻² (Crapsi et al. 2005), and the average N(H₂) of TMC-1 CP is (1.4 ± 0.1) × 10²² cm⁻² (Kauffmann et al. 2008). Relative abundances of sulphur-bearing molecules (main isotopologue) relative to CH₃OH (bottom).