And yes, the worms themselves take on some color before they produce silk.Their colorful diets did not affect their growth, the team, which included engineers and biologists from the CSIR—National Chemical Laboratory in India, reports in the journal ACS Sustainable Chemistry & Engineering.(The researchers didn't look too deeply into how the dyes affected the silkworms' health.After all, silkworms die when people harvest their silk.)
The team made dyeing silk this way because coloring fabric normally uses large amounts of fresh water.The water gets polluted with dangerous chemicals in the process, requiring costly treatment before factories can send it back into waterways.Dyeing silk directly by feeding silkworms would avoid those waterwashing steps.Scientists are just starting to study this idea.However, it remains to be seen if it's commercially successful.In this experiment, the Indian team tested seven dyes, which are cheap and popular in the industry.
The scientists found different dyes moved through silkworms' bodies differently.Some never made it into the worms' silk at all.Others colored the worms and their silk, but the color disappears before the silk is turned into fabric.Only one dye, named “direct acid fast red”, showed up in the final, washed silk threads.By the time it made it there, it was a pleasant, light pink.
【答案】 1-4 ADBA
【语篇解读】 本文是一篇说明文。你听说过蚕能吐出粉色的丝吗?印度的科学家做了大量的实验,他们通过给蚕喂一些喷过染色剂的桑树叶子,最终成功地使蚕吐出了粉色的丝。
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