探究点世界人口的分布特点5060NHr N-S0N北30N-40PNON220N赤道-rNuus1020S20-0S人口数量300S纬度20S-30S400S人口密度(人/千米)10010-10010口无人定居区图1世界人口分布图280海拔(米6020001500500200亚洲欧洲非洲北美洲南美洲大洋洲0102030405060距海岸200千米范围内陆地面积占洲总面积的比例占世界人口比例(%)距海岸200...
S Kenichiro,T Masahiro 摘要: PURPOSE: To obtain an oral cavity composition having remarkable suppressing effect on the formation of bacterial plaque and excellent caries preventive effect. ;CONSTITUTION: This composition for oral cavity application contains 1ppm to 20wt.% (especially 1ppm to 3wt.%...