The biodegradability of the copolymer of aconitic acid-acrylic acid (AA-AA), that is a new kind of scale inhibitor, was studied with shaking-bottle incubating test.

通过摇床实验，研究新型阻垢剂乌头酸丙烯酸共聚物(AA AA)的生物降解性。

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Then, if you weren't quite Aaa, you were Aa and if you weren't quite Aa, you were A and then you could become Ba.

于是,如果你达不到AAA,你就会是AA,如果你达不到AA,你就会是A,再往下就有可能是BA

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This has become the official mantra in many ways of the AA movement: "God, grant me the serenity to accept the things I cannot change; the courage to change the things I can change; " and wisdom to know the difference."

它已成为AA运动的正式圣言：,“主啊，请赐我安详，接纳我不能改变的事物;,请赐我勇气，去改变我可以改变的东西;,并赐我智慧去认识这两者的差别“

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He could only say aa aa aa, no more than that for some moment.

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The AA's Mr King said "76% of AA members are cutting back on journeys, household expenditure or both, due to the high cost of fuel".

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"Effective October 7, American will operate all JFK flights from the AA terminals with AA airplanes, " said Chairman Bob Baker in a statement to TWA employees.

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