## 3 Results and Discussion
### Analysis of VOCs Obtained by GC-IMS and GC-MS
\begin{table}
\begin{tabular}{r c c c c c c c} \hline \hline
**Compound** & **Number** & **CAS** & **RI** & **Fresh** & **YZ** & **XZ** & **CP** \\ \hline
**Ketones** & & & & & & & & \\
3-Methyl-1-2-Cyclopentanedione & M1 & 765-70-8 & 1631.1 & & & & & \\
3-Methyl-1-2-Cyclopenten-1-One & M2 & 2758-18-1 & & & & & \(0.275\pm 0.21\) & ---- \\
2,3-Octadione & M3 & 585-25-1 & 1334.7 & & & \(0.287\pm 0.23\) & ---- & ---- \\
2,3-Dimethyl-2-Cyclopentene-1-One & M4 & 1121-05-7 & 1538.1 & & \(0.078\pm 0.02\) & ---- & ---- \\ \hline
**Phenols** & & & & & & & \\
2,5-Dimethylphenol & M5 & 576-26-1 & 2099.1 & & & & 0.209 \(\pm\) 0.09 \\
2-Methylphenol & M6 & 95-48-7 & 2022.7 & & & \(0.487\pm 0.13\) & 0.362 \(\pm\) 0.17 \\
3-Methylphenol & M7 & 108-39-4 & & & & \(0.599\pm 0.26\) & 0.696 \(\pm\) 0.22 \\
4-Methyl Guaiacol & M8 & 93-51-6 & 1694.0 & & & \(0.522\pm 0.03\) & 0.415 \(\pm\) 0.11 \\
4-Ethylguaiacol & M9 & 2785-89-9 & 2059.9 & & & \(0.279\pm 0.12\) & 0.221 \(\pm\) 0.03 \\ Guaiacol & M10 & 90-51 & 1647.7 & & & \(0.735\pm 0.32\) & 0.567 \(\pm\) 0.27 \\ Phenol & M11 & 108-95-2 & 2028.9 & & & \(1.136\pm 0.46\) & 0.869 \(\pm\) 0.29 \\ \hline
**Alcohols** & & & & & & & \\ Ethanol & M12 & 64-17-5 & 939.6 & & \(16.017\pm 3.74\) & \(3.982\pm 1.01\) & 7.084 \(\pm\) 2.32 \\ Phenethyl Alcohol & M13 & 60-12-8 & 1673.0 & & \(0.135\pm 0.08\) & ---- & ---- \\
3-Octenol & M14 & 3391-86-4 & 1627.4 & & \(0.365\pm 0.43\) & \(0.129\pm 0.03\) & 0.241 \(\pm\) 0.01 \\ Furfuryl Alcohol & M15 & 98-00-0 & 1588.3 & & & \(0.320\pm 0.09\) & 0.241 \(\pm\) 0.01 \\
2-Methyl-1-Propanol & M16 & 7-83-1 & 1098.2 & & \(0.489\pm 0.23\) & & \(0.103\pm 0.01\) \\
3-Methyl-1-Butanol & M17 & 123-51-3 & 1214.0 & & \(5.757\pm 1.51\) & \(0.83\pm 0.03\) & 1.643 \(\pm\) 0.16 \\
1-Hexanol & M18 & 111-27-3 & 1360.1 & & \(0.146\pm 0.05\) & ---- & ---- \\
1-Pentanol & M19 & 71-41-0 & 1256.3 & & \(0.332\pm 0.07\) & \(0.083\pm 0.01\) & 0.063 \(\pm\) 0.03 \\ \hline
**Esters** & & & & & & & \\ Ethyl Acetate & M20 & 141-78-6 & 888.0 & & ---- & \(0.193\pm 0.01\) & ---- \\ Ethyl Octaonate & M21 & 106-32-1 & 1606.4 & & ---- & ---- & ---- \\ Ethyl Valerate & M22 & 539-82-2 & 1129.4 & & \(0.187\pm 0.03\) & ---- & ---- \\ Ethyl Caprate & M23 & 123-66-0 & 1241.8 & & \(1.131\pm 0.29\) & \(0.258\pm 0.11\) & 0.311 \(\pm\) 0.01 \\ Methyl Hexanoate & M24 & 106-70-7 & 1194.4 & & \(0.718\pm 0.37\) & 0.790 \(\pm\) 0.35 & 0.614 \(\pm\) 0.19 \\ Ethyl Caprate & M25 & 110-38-3 & 1574.6 & & ---- & \(0.191\pm 0.01\) & ---- \\ Ethyl Butyrate & M26 & 105-54-4 & 1041.8 & & \(0.342\pm 0.02\) & \(0.102\pm 0.02\) & \(0.168\pm 0.03\) \\ Methyl Butyrate & M27 & 623-42-7 & 990.1 & & \(0.460\pm 0.27\) & \(0.375\pm 0.11\) \\ Ethyl Lactate & M28 & 97-64-3 & 1356.9 & & \(0.104\pm 0.03\) & ---- & \(0.082\pm 0.03\) \\ \hline
**Aldehydes** & & & & & & \\ Pentanal & M29 & 110-62-3 & 986.6 & & \(0.112\pm 0.01\) & ---- & ---- \\ Hexanal & M30 & 66-25-1 & 1091.0 & \(0.203\pm 0.03\) & \(3.496\pm 0.85\) & \(0.834\pm 0.17\) & \(0.892\pm 0.26\) \\
1-Nonanal & M31 & 124-19-6 & 1419.2 & & \(0.323\pm 0.03\) & \(0.203\pm 0.03\) & 0.153 \(\pm\) 0.01 \\ Furfurral & M32 & 98-1-1 & 1680.2 & & \(0.762\pm 0.21\) & \(0.562\pm 0.01\) \\
5-Methyl Furfurral & M33 & 620-02-0 & 1552.3 & & \(0.760\pm 0.01\) & \(0.244\pm 0.03\) & \(0.173\pm 0.01\) \\ Acetal & M4 & 105-57-7 & 893.2 & & \(0.458\pm 0.03\) & ---- & ---- \\ \hline
**Others** & & & & & & \\
1,4-Dimethoxybenzene & M35 & 150-78-7 & 1767.6 & & \(0.158\pm 0.01\) & \(0.114\pm 0.02\) & \(0.185\pm 0.03\) \\ Naphthalene & M36 & 91-20-3 & 1784.9 & & \(0.105\pm 0.01\) & ---- \\
2-Acetylfuran & M37 & 1192-62-7 & 1516.7 & & \(0.326\pm 0.02\) & \(0.114\pm 0.02\) & ---- \\ Acetic Acid Glacial & M38 & 64-19-7 & 1640.4 & & \(0.742\pm 0.13\) & \(0.621\pm 0.24\) & \(0.448\pm 0.09\) \\ Pyridine & M9 & 110-86-1 & 1200.5 & & ---- & \(0.389\pm 0.01\) & ---- \\ Butyric Acid & M40 & 107-92-6 & 1570.6 & & ---- & \(0.104\pm 0.01\) & ---- \\ \hline \hline \end{tabular}  
* RI: Retention indexes; Represents the Chemical Abstracts Service; Fresh: raw sample; YZ: cured sample; XZ: smoking sample; CP: finished sample.  
\end{table}