排序方式: 共有55条查询结果,搜索用时 125 毫秒
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本文研究了强碱性条件下,以乙二胺为络合剂,用水合肼把二价镍离子还原为单质镍的方法。经过大量实验,镍粉的产率在99%以上,其纯度也在99%以上。通过这种方法,既回收了镍,又降低了对环境的污染,结果令人满意。 相似文献
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The data on plant growth conditions collected for 34 sites in the Barnsley and South Yorkshire Areas of the National Coal Board are analysed using methods of ordination and numerical classification in order to display the regional variations of plant growth characteristics. The potential value of such regional analyses and the manner in which such information could be used by reclamation agencies is discussed and a detailed example is presented for one site. The complete methodology and its limitations are reviewed and the implications for planning of reclamation projects discussed. 相似文献
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荒漠植物红砂研究进展 总被引:2,自引:0,他引:2
主要综述了荒漠植物红砂的分布区及其生境、解剖学特征、种子萌发及幼苗生长影响因素、组织培养、生理生态特征、繁殖及育苗、分子生物学特性等方面的研究。简要阐述了修复和重建红砂植被的必要性,并着重研究了红砂种子萌发的影响因素及育苗技术的发展现状,在此基础上指出红砂研究中的不足之处,并对今后的研究方向提出了建议。 相似文献
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