????? ?????? ??????? ?? ????? ????? ????? metatungstate ????????? (AMT) ?? ???? ?????? ?? ???? ??????? ??????? ????????? ????? ????? ????? ?????? ????????????? ????????? (APT)? ???? ??? ??? APT ??? ???? ??? ??????? ???????? ??????? ?? ????? ?? AMT ?????? ?????? ??????? ? ??? ?? ??? ??? ?? metatungstate ????????? ?????? ??? ????? ???? ?????? ?????? ??? metatungstate ????????? ???? ???? ??????.

??? ????????? ??????????? ???? ???? ?? ???????? ?????? ??? 180 ~ 260 ℃ ?????? AMT? ???????? ?????????? ?? ??? ????? ??????:
5(NH₄)₂O?12WO₃?H₂O=3(NH₄)₂O?12WO₃?3H₂O+4NH₃↑

????? ?????? ??????? ?? ??????? ??? ???? ??????? ???????? ???????? ??? ???? ??????? ?????? ??? ????? ???? ??? ????? ??????? ????? ????????. ?? ??? ?? ???? ????? ?????? ??? ??? ????? ?? ????? ??? ????? ?? ???????? ?????? ?? APT? ??? ???? ?? ???? metatungstate ?????????. ????? ????? ???????? ??????? ?? ??????? ??????? ?? ?????? ??????????? ????????? ????? ???? ????? ?? AMT. ???? ???? ????? ????? ?????? ?? ?????? ???????? ???? ?? ????? ?? ???? ???? ????? ?? ??? ????? ???? ??? ?? ??? ????? ???????? ??? ???? ???? ???? ??????? ?? ?????? ???????. ?????? ?????? ???????? ????? (??? ????? ??? ???????) ???? ?? ?????? ?????? ??????? ?????? ????? ????? ?? ??????????? ????????? ??? metatungstate ????????? ??? ??????? ??? ???? AMT.