<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31341327</termId><termName>photoacoustic spectroscopy</termName><termType>PT</termType><termNote><![CDATA[ Technique for measuring small absorptions, applied when small concentrations molecular species must be detected in the presence of other components at high pressure.  ]]></termNote><termCreatedDate>2026-03-30 20:32:03</termCreatedDate><relation><relationType>UF</relationType><termId>31341328</termId><termName>PAS</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31341329</termId><termName>optoacoustic spectroscopy</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31341330</termId><termName>spectroscopy, optoacoustic</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31341331</termId><termName>spectrosocopy, photoacoustic</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31317282</termId><termName>infrared spectroscopy</termName><termType>PT</termType></relation></term>  </Zthes>