The half - life of francium is 22 minutes.钫的半衰期是22分钟.Francium is the densest of the Alkali Metals and also radioactive.钫是碱金属中密度最大的,具有放射性.Even Francium's most stable isotope, Francium - 223 only has a half - life of ...
The Dunhuang frescoes are gems of ancient Chinese art.敦煌壁画是我国古代艺术中的瑰宝.The painted murals in the Dunhuang Grottoes along the ancient Silk Road in China form the world's longest painted corridor , with a total of 45,0...
They also left a card, imprinted with the name Sean Lynch.他们还留下了一张名片,上面印着肖恩·林奇的名字。Lisa was irritated by the slovenly attitude of her boyfriend Sean.莉萨对男朋友肖恩吊儿郎当的态度非常恼火。Sean's a fast thinker, and he acts on impulse.肖...
她属于那种自负得从不听别人劝告的人.She is one of those vain people who never take others'advice.更阴沉的恐惧心,也许可以说是几分天良,代替了那座大厅里的劝告的声音.Darker fears or better impulses supplanted the counsel of the voice in the great hall.劝告是很少受到欢迎的; 最需要劝...