1. Later Thoreau converted the factory to producing plumbago, used to ink typesetting machines. 随后梭罗让工厂转换生产适用于油墨排版机的石墨粉。
2. But it was not until 1779 that Swedish chemist Carl Scheele showed that plumbago is carbon, not lead. 直到1779年,瑞典化学家谢勒(CarlScheele)才发现黑铅其实是碳而不是铅。
3. The plumbago auriculata family take Madele as a head, but the green dragon family by Youbudeni, two family each other manipulates strategically many years for the throne inheritance. 蓝花家族以马
英英解释
n.
1. used as a lubricant and as a moderator in nuclear reactors
2. any plumbaginaceous plant of the genus Plumbago