Steel backed-tin bronze bi-metallic sleeve can be used to substitute all bronze sleeves due to its low manufacturing cost, better wearing quality and longer service life.
钢背-锡青铜双金属衬套制造成本低、磨损率小、使用寿命长，可取代全青铜衬套。
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A new criterion to decide whether the carboxy group coordinating to the metallic ion in mono or bi dentate-fashion in an ambiguous situation, base on coordination bond distances and angles.