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A dog from New Iberia, La., named Max, is vying for the record of world's oldest dog.

目前，来自路易斯安那州新伊比利亚的一只名为的狗正在竞争世界最长寿狗的纪录。

For studying the process and result of nitrogen pollution and transformation in agricultural areas in different situations, four sand column experiments were done.

为研究不同条件下农田区氮污染和氮转化的过程及结果，进行了4个土柱的模拟实验。