课程咨询

托福考试网 托福资料下载 托福资讯 0元讲座 水平测试

托福考试练习
新东方在线 > TOEFL > 托福听力 > 正文
托福培训

扫码免费领资料

托福全科备考资料

免费水平测试及规划

托福培训

扫码关注掌握一手留学资讯

回复XDF免费水平测试

录播精讲 直播课HOT

托福听力练习-科学美国人60秒:梵高《向日葵》

2017-05-26 08:59:00来源：科学美国人60秒

点击查看>>科学美国人60秒音频：梵高《向日葵》

　　科学美国人60秒听力练习：梵高《向日葵》

　　科学美国人60秒英文文本

　　Imagine van Gogh’s paintings of yellow sunflowers. Now imagine the flowers brown. Eh, not so good. Sadly, we may someday see what that would look like. Because the bright yellow paints on the canvas are slowly turning muddy. Now, an international team of scientists has pinpointed the chemical reaction that drives this degradation—the first step toward stopping it. Their findings appear in the journal Analytical Chemistry. [Letizia Monico et al., "Degradation Process of Lead Chromate in Paintings by Vincent van Gogh Studied by Means of Synchrotron X-Ray Spectromicroscopy and Related Methods. 1. Artificially Aged Model Samples and 2. Original Paint Layer Samples"]

　　Van Gogh’s use of strong bright colors to convey mood and emotion marks a major milestone in art history. And his Sunflower series wouldn’t be the same without the vibrant “chrome yellow” pigment that was new at the time. But this color darkens when exposed to the sun.

　　To find out why, researchers used sophisticated x-ray analyses to determine the exact chemical composition of the paint as it browns. First, they exposed three tubes of chrome yellow to UV radiation until one turned a chocolate color. Analyzing that sample, they identified specific changes in the paint’s chromium compounds. They then found the same chemical signature in the darkened areas of two van Gogh paintings. Until a chemical antidote is found, the researchers have some ironic advice: keep sunlight away from van Gogh’s sunflowers.

　　—Karen Hopkin

　　中文翻译请点击下一页

本文关键字: 托福听力 科学美国人60秒

上一页 1 2 下一页

托福辅导

关注新东方在线托福

托福机经·Official题目练习

考前重点突破·听说读写海量资料

更多资料

关注新东方在线托福，
回复【XDF】获取大礼包

托福辅导
  • 1.打开手机微信【扫一扫】，识别上方二维码；
  • 2.点击【添加】，回复对应关键字领取学习资料。
更多>>
更多内容

免费获取托福备考大礼包

微信扫描下方二维码 立即领取

托福辅导
更多>>
更多公益讲座>>
更多>>
更多资料
托福TPO 托福听力练习 托福口语练习 托福阅读练习 托福写作练习
我要
反馈 返回
首页
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10