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GB T 1 2 2 1 - 1 992是参照JISG431 1制定的 ,与其他发国家标准也有较好的通用性 ,总体上达到了国际一般水平 ,在低倍组织和化学成分等方面具有国际先进水平。
GB T 1 2 2 1 - 1 992 is developed in accordance with JIS G431 1 and has good commonality with other national standards. It has generally reached the international general level and has world-class advanced level in low magnification organizations and chemical compositions.