???? ???????????? ??? ?????? ???????????? ???? ?????????? ??????????????????, ??? P2O5 ???? ???????????????? ???????????? ?????????? ????????????, ??? ???? ?????? ?????????????? ??????? ??????? ????? ??????????? ??????, ???? ???? SiO2 73.0, B2O3 11.70, Al2O3 3,O52, (9.6-(X+Y)), CaO (X=0.1-050) ??????? BaO (Y=4.5-2.9)wt%. ??????????? ?????????? Na2O, CaO ??????? BaO ??????????? ????????? ???????????, ???? ??????? ?????? ????? ??????? ??? ??????? ??????????? ???????????. ????????? Na2O/ BaO + CaO ??? ??????????????? ??????????? ??????? ?????? ?????????? ?????????. ???? ????????? ??????????? ??????????? ????????????? ??????? ?????? ???????????????? ????????? 28 ???? 2008 ??? ?????????? ???. 49441 ?? ????? ?????????????.
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