雅思阅读材料之浮法玻璃

　　阅读段落

　　The principle of float glass is unchanged since the 1950s. However, the product has changed dramatically, from a single thickness of 6.8 mm to a range from sub-millimeter to 25mm, from a ribbon frequently marred by inclusions and bubbles to almost optical perfection. To ensure the highest quality, inspection takes place at every stage. Occasionally, a bubble is not removed during refining, a sand grain refuses to melt, a tremor in the tin puts ripples into the glass ribbon. Automated on-line inspection does two things. Firstly, it reveals process faults upstream that can be corrected. Inspection technology allows more than 100 million measurements a second to be made across the ribbon, locating flaws the unaided eye would be unable to see. Secondly, it enables computers downstream to steer cutters around flaws.

　　段落大意

　　本段介绍了浮法玻璃产品的一些新变化。

　　阅读笔记

　　Dramatical change of the product:

　　1.thickness: a single thickness of 6.8 mm <> a range from sub-millimeter to 25mm

　　2.quality: a ribbon frequently marred by inclusions and bubbles<> almost optical perfection

　　3.inspection: automated on-line inspection

　　逻辑关系

　　1. 对比(逻辑连接词: HOWEVER)

　　The principle of float glass is unchanged since the 1950s.

　　The product has changed dramatically, from a single thickness of 6.8 mm to a range from sub-millimetre to 25mm, from a ribbon frequently marred by inclusions and bubbles to almost optical perfection.

　　2. 并列(逻辑连接词: FIRSTLY, SECONDLY)

　　It reveals process faults upstream that can be corrected.

　　It enables computers downstream to steer cutters around flaws.