Unit 2　Making a difference(课件)-【优化探究】2021-2022学年新教材高中英语必修第三册同步导学案（外研版）

返回导航 下页 上页 外研英语 必修 第三册 单元知识目标 重点词汇：contribution; relief; shortage; effective; fund; recycle; earn; donate; reality; extend; mission; disease; disability; sensitive; generous; hesitate; assistance; confirmation; aid; temporary; achievement; chief; major; treatment; obtain; further 重点短语：break into a smile; turn out; make a difference; set up; benefit from; rise to one's feet; bring...to public attention; pass away 单元语法：过去分词(短语)作定语 单元写作：人物传记 返回导航 下页 上页 外研英语 必修 第三册 主题语境 情境导入 返回导航 下页 上页 外研英语 必修 第三册 华人科学家造出透明木头。 Scientists have come up with a revolutionary new use for wood. They have devised a way to make it transparent. This could totally change the way many things in our lives are used and made. See­through wood could one day replace glass and be used in windows and 返回导航 下页 上页 外研英语 必修 第三册 tables，and in a whole assortment (分类) of other building materials.The innovation (创新) has come from researchers at the University of Maryland in the USA.They experimented with different ways to extract the chemicals from wood that give it colour.Researcher Liang Binghu said: “We were very surprised by how transparent it could go.This can really open applications that can potentially replace glass and some optical materials.” 返回导航 下页 上页 外研英语 必修 第三册 The researchers worked with a small block of linden (菩提树)．They boiled it in water，sodium hydroxide (氢氧化钠) and other chemicals for about two hours.A molecule called lignin，which gives wood its colour，disappeared during the boiling process.This left behind colourless cells，which effectively made the wood transparent. The see­through wood is a lot stronger and less dangerous than glass. It is 返回导航 下页 上页 外研英语 必修 第三册 better at insulating against the cold and it is biodegradable (能进行生物降解的)．Research is still in its infancy and the process can currently only be done on 10 cm by 10 cm blocks of wood that range in thickness between paper­thin and a centimeter thick.The researchers will now focus on applying the process t