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2, ???? ???? ??? ??????
???? ?? ?? ??? ??? ?????? ????? ?? ?? ??? ???? ???? ??? ?2.6 ??? 3.6 ?????? ????? ???? ????? ?????? ???? ???? ????? ??? ??? ???? ????
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???? ????? ??? ?? ????? ??? ??? ?? ?? ?? ??? ??? ????? ????? ??? ???? ????? (Mx): ???? ?????? ???? ?? ???? ????
???? ??? ??? (fineness modulus) ?3.7-3.1 ???? ???? ??? ?0.5 ?? ??? ??? ???
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??? ??? ???? ??? 2.2-1.6? ???? ???? ??? 0.35??-0.25?? ???
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???? ??? ??? ????? ??? ???? ???? ?? ????? ???? ??? ??? ????? ??? ???? ???? ?? ?????
3? ???? ???? ??? ???? ?? ???
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??? ??? ??? ??30 ??? ??? ?????? ?? ????? ???? ???? ??? ???? ???? ???
4, ???? ???? ??? ??????
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6. ??? ???? ??? ????? ???? ?? ????
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8. ???? ???? ??? ?????
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????? ??? ?? ???? ??? ???? ??? ??? ??? ??? ???? ???? ???? ??? ???? ??? ??? ??? ?? ?? ???? (bleeding) ?????? ?????
????? ????? ???? ??? ???? ??????? ???? ??? ?? ???? ???? ??? ?? ?? ??? ????? ??? ????? ?????? ??? ???? ??? ?? ??? ??? ?2.6-3.0 ???? ???? ?? ??? 2 ??? ????
9, ???? ???? ??? ????? ?????
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