David Beckmann became President of Bread for the World in 1991.

大卫·贝克曼1991年就任“赈济饥民会”的总裁。

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The low carbon alcohols were the most effective solvent for the Beckmann reaction.

结果表明，低碳醇适宜作反应溶剂；

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The low carbon alcohols were the most effective solvent for the Beckmann reaction.

结果表明，低碳醇适宜作反应溶剂；

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