亚历山大·格雷厄姆·贝尔是发明家及飞行术先驱。图为1930年代，他帮助一个男孩在一架西科斯基s - 38水陆两栖飞行器的浮筒上保持平衡。
Alexander Graham Bell, inventor and aviation pioneer, helps a boy balance on the pontoon of a Sikorsky S-38 amphibious aircraft in the 1930s.
目的了解武汉城区居民住宅、一般单位、重点单位室内家栖鼠种群构成。
Objective To investigate indoor commensal rodent population structure in populated area, general institutions and emphasis institutions indoor in Wuhan.
目的探讨家栖鼠对抗凝血杀鼠剂的抗药性变化。
Objective To study the anticoagulant rodenticide resistance in commensal rodents.
应用推荐