科学美国人60秒 SSS Concrete Defects Could Become Strengths
时间：2018-12-18 作者：英语课 分类：2017年Scientific American(一)月
Concrete is one of the most widely used materials on the planet. "And this consumption comes with a heavy ecological 1 price." Rouzbeh Shahsavari, a materials scientist at Rice University. "Around 5 to 10 percent of total CO2 emissions 2 comes from concrete production."
One way to reduce those emissions, he says, would be to increase the strength and toughness of concrete. So you need less of it in construction. But to make something stronger, you need to understand its weaknesses.
So Shahsavari and his team studied the defects in a rock called tobermorite. (TO-ber-MOR-ite) The rock is an analog 3 for wet cement, the main ingredient in concrete. And they found that certain defects in the rock actually made the rock tougher, if they were aligned 4 in a specific configuration 5. Sounds counterintuitive: Defects a good thing?
"Defects are typically considered a bad feature of material. But when it comes to complex systems, like cement or concrete, it's not the case. It may actually be an opportunity to introduce toughness, or get something better out of it." The study is in the journal ACS Applied 6 Materials and Interfaces 7. [Ning Zhang, Philippe Carrez, and Rouzbeh Shahsavari, Screw Dislocation-Induced Strengthening-Toughening Mechanisms 8 in Complex, Layered Materials: The Case Study of Tobermorite]
Next step, Shahsavari says, would be to optimize 9 concrete recipes—to use these defects in their favor. Play with manufacturing temperatures, or alter the ratios of impurities 10 in the mix. "Since we're using it pretty much in every building, every bridge, every highway in all parts of the world, even a slight impact in the performance could have a huge consequence in terms of energy consumption, CO2 footprint, and all those things." And take a little concrete out of the concrete jungle.
—Christopher Intagliata
- The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
- Each animal has its ecological niche.每种动物都有自己的生态位.
- Most scientists accept that climate change is linked to carbon emissions. 大多数科学家都相信气候变化与排放的含碳气体有关。
- Dangerous emissions radiate from plutonium. 危险的辐射物从钚放散出来。
- The analog signal contains high-frequency video information,which helps make up the picture.模拟信号包括有助于构成图像的高频视频信息。
- The analog computer measures continuously,without proceeding step by step.模拟计算机不是一步一步地进行，而是连续地进行量度。
- Geographers study the configuration of the mountains.地理学家研究山脉的地形轮廓。
- Prices range from $119 to $199,depending on the particular configuration.价格因具体配置而异，从119美元至199美元不等。
- She plans to take a course in applied linguistics.她打算学习应用语言学课程。
- This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。
- If the class needs to be reprogrammed, new interfaces are created. 如果class需要重新程序设计，新的interfaces创建。
- Interfaces solve this problem of evolving code. Interfaces解决了代码升级的问题。
- The research will provide direct insight into molecular mechanisms. 这项研究将使人能够直接地了解分子的机理。 来自《简明英汉词典》
- He explained how the two mechanisms worked. 他解释这两台机械装置是如何工作的。 来自《简明英汉词典》
- We should optimize the composition of the Standing Committees.优化人大常委会组成人员的结构。
- We should optimize our import mix and focus on bringing in advanced technology and key equipment.优化进口结构，着重引进先进技术和关键设备。
- A filter will remove most impurities found in water. 过滤器会滤掉水中的大部分杂质。
- Oil is refined to remove naturally occurring impurities. 油经过提炼去除天然存在的杂质。