The split graph is given endomorphism images are retracts.给出了任意自同态像图都是收缩核的分裂图的结构.In this paper, split graphs with complete endomorphism - regularity are characterized explicitly.本文给出了具有完全正则自同态半群的分裂图的结构特征....
The savanna is also the home of meat - eaters — the lion, leopard, and hyena who feed on the grasseaters.大草原也是食肉动物的家乡--狮子 、 豹 、 鬣狗--它们都是以草食动物维持生命的.The hyena's public image is not aided by its ridiculous appearance.鬣...
A lustrous, blackish - brown rare earth mineral consisting primarily of cerium , erbium , titanium , uranium, and yttrium.一种红褐色矿物, 含稀土金属, 是钍和铈的主要来源.The titanium ascorbate was the substance of low toxicity to fish, shellf...