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用法例句

A low-cost low-temperature sand control agent has been developed by optimizing the structure of phenolic resin and synthesizing low-cost resin with coal tar and paraformaldehyde.

对酚醛树脂结构进行优化,合成出高效酚醛树脂,加入以煤焦油和多聚甲醛为原料合成的廉价树脂,研制出廉价低温防砂剂。