PTE考生目前最大的问题之一就是练习题缺乏。除了有限的基本官方书（PLUS，Testbuilder, OG）之外
就没有题了。很多英语基础不是很扎实的同学很难找到练习材料。悉尼文波雅思PTE培训学校专门为澳洲，尤其是悉尼、墨尔本的PTE考生准备了适合PTE听力阅读练习的科学60秒。各位PTE同学可以练习PTE听力中的summarise spoken text和PTE口语中的retell lecture，PTE听力口语-科学60秒-Frosty Moss练习记笔记技巧和复述。废话少说，下面开始：
听力内容：
60秒科学节目（SSS）是科学美国人网站的一套广播栏目，英文名称：Scientific American – 60 Second Science,节目内容以科学报道为主，节目仅一分钟的时间，主要对当今的科学技术新发展作以简明、通俗的介绍，对于科学的发展如何影响人们的生活环境、健康状况及科学技术，提供了大量简明易懂的阐释。
Every winter some 20 million tons of salt are dumped on America’s roads.
The sodium chloride melts ice or prevents its formation, helping to prevent accidents.
But road salt has its downsides.
“This is actually not very economical, because salt is mainly corrosive.”
Seda Kizilel, a chemical engineer at Koc University in Istanbul, Turkey.
She says salt’s corrosive effects don’t discriminate—they affect “vehicles and also nature, plants, microorganisms.”
So Kizilel and her colleagues designed a road substance that can de–ice itself.
They started with a polymer called SBS, commonly added to strengthen asphalt.
They whipped up an emulsion of SBS with potassium formate,
an alternative salt that’s been studied as a more environmentally friendly de–icer than regular road salt.
Then they added that emulsion to bitumen–the sticky black stuff in asphalt.
They subjected their creation and regular bitumen to the winter weather conditions that typically lead to black ice.
Turns out the hybrid compound delayed ice formation 10 minutes longer than the control.
And the samples continued releasing salt for more than two months.
The study is in the journal Industrial & Engineering Chemistry Research.
Of course, 10 minutes of de–icing is a nice head start—but it’s not going to put salt truck drivers out of business.
“But we’re saying that, during the first 10 to 15 minutes, when the road becomes very icy, this material and this release of salt from this functional bitumen is going to be very useful and potentially eliminate many accidents on the roads.”
The next step, she says, is to pave a test surface and drive on it–to literally see what happens when the rubber meets the road.
词语提示：
Chloride [ˈklɔ:raɪd] n. 漂白粉、氯化物
Corrosive [kəˈrəʊsɪv] adv. 腐蚀性的； 侵蚀性的
Microorganisms [mɪk’rɔːɡənɪzəmz] n. 微生物
Emulsion [ɪ’mʌlʃn] n.乳状液；感光乳剂
Potassium [pə’tæsiəm] n.钾
悉尼文波PTE原创首发
