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What Makes Windshield Glass So Tough? We tend to think of glass as fragilebut in fact, glass is pretty strong stuff. A flawless fiber of glass pulled lengthwise is five times stronger than steel! Although glass is quite strong, its also very brittlea
By Ted Landphair Washington 09 August 2007 Every day, American consumers are offered a simple choice when they areby a store's cashier: paper or plastic? But as VOA's Ted Landphair explains in today's searching for solutions report, some communities
Pakistan's Bonded Laborers Trapped in Cycle of Debt 巴基斯坦契约劳工陷入债务圈套 ISLAMABAD In Pakistan today, more than 2 million people, including children, work as bonded laborers, a system the United Nations describes as modern-day s
Its amazing to think there wasnt any plastic one hundred years ago. Now its everywhere. Almost everything thats made has some plastic in it. Whoever invented it must be really rich. There are all kinds of plastic. Its pretty useful stuff. I once went
Why Teflon Is Slippery Teflon is the trademark name for PTFE, a type of plastic. If you own any non stick cookware, then you probably use PTFE on a daily basis. You might not realize, as you fry your morning eggs, that PTFE is one of the most slipper
Why Teflon Is Slippery? 1954年,法国工程师马克格雷瓜尔(Marc Gregoire)的妻子柯莱特(Colette)突发奇想,觉得丈夫用来涂在钓鱼线上防止打结的不粘材料特氟龙(Teflon)如果可以用在煎锅上,效果一定不错