<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31373606</termId><termName>alumina</termName><termType>PT</termType><termNote><![CDATA[ A synthetically produced aluminum oxide, a white or nearly colorless crystalline substance that is used as a starting material for the smelting of aluminum metal, as the raw material for a broad range of advanced ceramic products, and as an active agent in chemical processing. Alumina is derived from bauxite, a naturally occurring ore containing variable amounts of hydrous aluminum oxides. ]]></termNote><termCreatedDate>2026-03-30 20:40:45</termCreatedDate><relation><relationType>BT</relationType><termId>31343400</termId><termName>aluminum oxide</termName><termType>PT</termType></relation></term>  </Zthes>