<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31343575</termId><termName>zirconium</termName><termType>PT</termType><termNote><![CDATA[ Zirconium is a metallic element having symbol Zr and atomic weight 91.22. It is obtained from zircon and other minerals and is commercially the most important ore. A hard metal resistant to heat and corrosion, it is much used in nuclear reactors, in alloys, refractories, and ceramics. ]]></termNote><termCreatedDate>2026-03-30 20:32:39</termCreatedDate><relation><relationType>UF</relationType><termId>31343576</termId><termName>Zr</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31375243</termId><termName>nonferrous metal</termName><termType>PT</termType></relation><relation><relationType>BT</relationType><termId>31319740</termId><termName>elements</termName><termType>PT</termType></relation><relation><relationType>RT</relationType><termId>31344512</termId><termName>zircon</termName><termType>PT</termType></relation></term>  </Zthes>