排序方式: 共有6条查询结果,搜索用时 15 毫秒
1
1.
2.
3.
4.
从李白关于庐山瀑布的名诗谈起,讨论了瀑布的成因.作为例子欣赏了我国的黄果树瀑布、壶口瀑布,以及美加之间的尼亚加拉瀑布.分析了水力发电的优缺点,指出要重视过度开发水力资源对生态文明的破坏. 相似文献
5.
6.
A phosphorus-containing monomer (10-oxo-10-hydro-9-oxa-10λ5-phospha-phenanthrene-10-yl)-methyl acrylate (M1) was copolymerized with styrene to give a potential flame retardant copolymer of high thermal stability. The structures of monomer and copolymer were characterized by FT-IR and 1H NMR measurements. The reactivity ratios for free-radical of the monomer (M1) and styrene (M2) were studied. The calculated results are as follows:r1=0.225, r2=0.503; Q1=0.413, e1=0.476; azeotropic point=0.37. TGA and DTG curves indicated that M1 is a potential flame retarding monomer for styrenic polymers. 相似文献
1