???? 28? ?? ????? ??? 8? ??? ?? ??? ?? ???? ??????, ???? ?? ?? ??????, ???? ?? ?????? ? 6?? ??? ?????? 1??? ????? ???.

??? ??? ??????,???? ??????, ???? ?????? ?? ??? ?????(COD)????? ?????? 2??? ????? ???? ??????? ??????? ??? ?? ???.

?? ???? ???? ????? ??? △?????(CD) 6.6～7.6PPM △??? ?????(COD)0.5～1.5PPM △?????(SS) 3.4～9.1PPM ?? ???? ????.

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