The results show that in the same H & A, with depth of soil increasing, contents of organic matter(OM), NO-3-N, available phosphor(AP) and urease decreased respectively.

结果表明，对于同一封育年限的油松林地，土壤有机质、硝态氮、速效磷和脲酶含量随采样深度增加而减小；

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This paper presents a new no shadow-mask colour picture tube with three-in-line electron gun and linear phosphor strips.

本文提出了一种三束一字型具有线形荧光粉条的新型无荫罩彩色显像管。

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