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  <xsd:element abstract="true" id="ntic_statement-statement-note-7-investments-in-joint-ventures-condensed-balance-sheet-of-excor-and-all-other-joint-ventures-details07ABB4DF-2E41-4F9C-92DB-9FB3958C93A1" name="statement-statement-note-7-investments-in-joint-ventures-condensed-balance-sheet-of-excor-and-all-other-joint-ventures-details07ABB4DF-2E41-4F9C-92DB-9FB3958C93A1" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
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  <xsd:element abstract="true" id="ntic_statement-statement-note-8-stockholders-equity-cash-dividends-declared-details" name="statement-statement-note-8-stockholders-equity-cash-dividends-declared-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ntic_statement-statement-note-9-stockholders-equity-tables" name="statement-statement-note-9-stockholders-equity-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
