. 2020 Jul 16;5(29):17926–17930. doi: 10.1021/acsomega.0c00839

Table 1. Background Analysis of δ¹³C–CO₂ (VPDB) and δ¹⁸O–CO₂ (VPDB) Without the Use of a Pressure Regulator (Gas Expansion Only) and of δ¹³C–CO₂ E(VPDB) and δ¹⁸O–CO₂ (VPDB) Obtained with the Use of a Pressure Regulator^a.

	δ¹³C (‰)	δ¹⁸O (‰)	Δ¹³C (‰)	Δ¹⁸O (‰)
background	–24.50 ± 0.05	–24.99 ± 0.05
0.14 bar	–24.48 ± 0.03	–25.01 ± 0.06	0.00 ± 0.08	0.02 ± 0.11
0.21 bar	–24.49 ± 0.04	–25.00 ± 0.07	0.01 ± 0.09	0.01 ± 0.12
0.34 bar	–24.47 ± 0.04	–24.98 ± 0.06	0.00 ± 0.09	–0.01 ± 0.14
0.54 bar	–24.47 ± 0.04	–24.98 ± 0.06	0.01 ± 0.09	–0.01 ± 0.11
0.82 bar	–24.51 ± 0.05	–25.01 ± 0.05	0.01 ± 0.10	0.02 ± 0.10

Δ¹³C and Δ¹⁸O represent the difference between pressure reduction by sequential volumetric expansion and pressure reduction with a pressure regulator.

Table 1. Background Analysis of δ13C–CO2 (VPDB) and δ18O–CO2 (VPDB) Without the Use of a Pressure Regulator (Gas Expansion Only) and of δ13C–CO2 E(VPDB) and δ18O–CO2 (VPDB) Obtained with the Use of a Pressure Regulatora.

Table 1. Background Analysis of δ¹³C–CO₂ (VPDB) and δ¹⁸O–CO₂ (VPDB) Without the Use of a Pressure Regulator (Gas Expansion Only) and of δ¹³C–CO₂ E(VPDB) and δ¹⁸O–CO₂ (VPDB) Obtained with the Use of a Pressure Regulator^a.