Until today germanium is the present substance on earth with no exception.直至今天锗才毫无异议地成为地球上是纯净的物质.Doped silicon and germanium are technologically the most important types of semiconducting material.添加硅和锗在工艺上是半导体物质中最重要的类型....
But by the year 2020 business computing will have changed beyond recognition.但是到了2020年，商业计算会变得面目全非。Many graduates are employed in the electronics and computing industries.很多毕业生就职于电子和计算机行业。McNally has spent 17 years at th...