## 3 Results
with the frequency from on-line database f\({}_{\text{1 cat}}\) = 134.9084537 GHz for the transition with quantum numbers 7 4 4 0\(\leftarrow\)6 4 3 0 [15], f\({}_{\text{12 cat}}\) = 134.9086558 GHz for the transition with quantum numbers 7 4 3 0\(\leftarrow\)6 4 2 0 [15]), f\({}_{\text{lexp}}\) = 134.9222 GHz (f\({}_{\text{2 cat}}\) = 134.9222164 GHz for the transition with quantum numbers 7 4 3 2\(\leftarrow\)6 4 2 2 [15]), f\({}_{\text{lexp}}\) = 134.9334 GHz (f\({}_{\text{3 cat}}\) = 134.9333724 GHz for the transition with quantum numbers 7 4 4 1\(\leftarrow\)6 4 3 1 [15]), f\({}_{\text{lexp}}\) = 134.9633 GHz (f\({}_{\text{4 cat}}\) = 134.9632399 GHz for the transition with quantum numbers 7 3 5 0\(\leftarrow\)6 3 4 0 [15]), f\({}_{\text{gexp}}\) = 134.9729 GHz (f\({}_{\text{5 cat}}\) = 134.9730698 GHz for the transition with quantum numbers 7 3 4 2\(\leftarrow\)6 3 3 2 [15]), f\({}_{\text{gexp}}\) = 134.98705 GHz (f\({}_{\text{6 cat}}\) = 134.9872121 GHz for the transition with quantum numbers 7 3 4 0\(\leftarrow\)6 3 3 0 [15]) and f\({}_{\text{expxp}}\) = 134.996 GHz (f\({}_{\text{7 cat}}\) = 134.9960633 GHz for the transition with quantum numbers 7 3 5 1\(\leftarrow\)6 3 4 1 [15]). There are two close lines near the first frequency f\({}_{\text{lexp}}\) in on-line database. These two lines overlap and are detected as one. A comparison of the chemical composition of the gas mixture of the thermal decomposition products for polyp and relatively healthy tissue is shown in Figure 6 (polyp tissue Sample No. 6 and healthy tissue Sample No. 3). It can be seen, firstly, that new substances appear in the composition of the gas mixture of the thermal decomposition products for the polyp compared to a relatively healthy mucosa (hydroxyacetone, dihydroxyacetone, propionitrile, including isotopologue with isotope C, aminoproponitrile, acetonitrile, monoethanolamine, alanine, pyridine, furan, and phenylacetylene) and the concentration of a number of substances (methyl mercaptan, acetaldehyde, methanol, propanediol, butyronitrile, pentannitrile, azole, diketene, sulfur dioxide, and ethylene sulfide) is increasing. The composition of the thermal decomposition products of polyp tissue has both a general difference from relatively healthy tissue, and its own characteristics depending on the age of the patient. The etiology of chronic polypous rhinositis with regard to metabolomics is a subject for further study as a part of the research. An example of comparing the chemical composition of thermal decomposition products for two samples (No. 4 for children and No. 5 for adults) is shown in Figure 7.  
The figure shows a general coincidence in chemical composition for both samples; however, there are also specific features: the level of acetonitrile and acetaldehyde for a gas mixture of thermal decomposition products of the polyp sample taken from the adult is higher than for the sample taken from the child. Figure 5: Example of recording a spectrum section containing acetonitrile (CH\({}_{3}\)CN) lines for a polyp tissue sample (No. 6) with experimentally measured central frequencies f\({}_{\text{leep}}\)= 147.1633 GHz (f\({}_{\text{lcat}}\)= 147.1632441 GHz for a transition with quantum numbers 8 2\(\leftarrow\)7 2 [15]), f\({}_{\text{leep}}\)= 147.1718 GHz (f\({}_{\text{lcat}}\)= 147.17159 GHz for a transition with quantum numbers 8 1\(\leftarrow\)7 1 [15]), and f\({}_{\text{leep}}\)= 147.1746 GHz (f\({}_{\text{lcat}}\)= 147.1745883 GHz for a transition with quantum numbers 8 0\(\leftarrow\)7 0 [15]).