Virtual reconstruction of the painting process and original colors of a color-changed Northern Wei Dynasty mural in Cave 254 of the Mogao Grottoes

Heritage Science

Table 4 LC/MS detection of pigment samples in the salmon luminescent region

Compound	Molecular formula	Rt/min	Molecular ion peak [M-H]- m/z	Fragment ions (m/z)
Shellolic acid	C₁₅H₂₀O₆	1.22	295.1185	251.1286/249.1133/177.1284/121.0650
Oxidized shellolic acid	C₁₅H₁₈O₆	2.25	293.1027	249.1129/205.1234/109.0659/83.0503
Jalaric acid	C₁₅H₂₀O₅	2.99	279.1235	261.1129/235.1335/217.1230/147.0449/119.0503
Aleuritic acid	C₁₆H₃₂O₅	3.72	303.2176	285.2070/267.1967/201.1138/171.1024/127.1125
Laccaic acid A	C₂₆H₁₈O₁₂N	5.72	536.0840	492.0943/448.1038/430.0930
Jalaric acid ester	C₂₄H₃₃O₉	4.51	465.2125	277.1078/187.0973/233.1180/147.0450/465.2130
16-hydroxyhexadecanoic acid	C₁₆H₃₁O₃	9.10	271.2276	271.2274/225.2220/253.2168/141.1281/113.0972