<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31373709</termId><termName>sulfur oxide</termName><termType>PT</termType><termNote><![CDATA[ Any of several gaseous compounds of sulfur and oxygen, most importantly sufur dioxide and sulfur trioxide. Sulfur oxides are responsible for about 18 percent of the total average pollutant content of air. ]]></termNote><termCreatedDate>2026-03-30 20:40:46</termCreatedDate><relation><relationType>UF</relationType><termId>31373710</termId><termName>oxide, sulfur</termName><termType>ND</termType></relation><relation><relationType>UF</relationType><termId>31373711</termId><termName>sulfur oxides</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31343453</termId><termName>sulfur compounds</termName><termType>PT</termType></relation></term>  </Zthes>