SSS 2008-04-03
时间：2019-01-08 作者：英语课 分类：Scientific American(四)月
This is Scientific American’s 60-Second Science, I am Cynthia Graber .This will just take a minute.
How can we improve engines, inhalers and fire extinguishers? Maybe by copying a beetle 1. The bombardier beetle's name might scare off predators 2 if they knew it.To protect itself the beetle shoots a spray of hot toxic 3 venom 4. The spray can travel nearly 8 inches about 2000 times the length of the insect's combustion 5 chamber 6. Scientists from Leeds University and from Swedish Biomimetics 3000 reported on this propellant abilities in the April issue of Physics World. Hydroquinone and hydrogen peroxide build up in the insect's abdomen 7. When the beetle needs protection the chemicals flood the combustion chamber. In the presence of a catalyst 8, the chemicals create a toxin 9 along with other compounds and water. The reaction heats to near boiling. When the pressure is high enough a membrane 10 at the other end of the combustion chamber opens and the mist and liquid fires. The pressure drops and the combustible 11 chemicals quickly refill the chamber leading to a series of bursts. Scientists modeled and replicated 12 the system using hot water instead of venom. They say it could offer huge power and environmental benefits of a current high-performance spray technologies.
Thanks for the minute. For Scientific American’s 60-second Science. I am Cindy Graber.
- A firefly is a type of beetle.萤火虫是一种甲虫。
- He saw a shiny green beetle on a leaf.我看见树叶上有一只闪闪发光的绿色甲虫。
- birds and their earthbound predators 鸟和地面上捕食它们的动物
- The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
- The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
- There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。
- The snake injects the venom immediately after biting its prey.毒蛇咬住猎物之后马上注入毒液。
- In fact,some components of the venom may benefit human health.事实上，毒液的某些成分可能有益于人类健康。
- We might be tempted to think of combustion.我们也许会联想到氧化。
- The smoke formed by their combustion is negligible.由它燃烧所生成的烟是可忽略的。
- For many,the dentist's surgery remains a torture chamber.对许多人来说，牙医的治疗室一直是间受刑室。
- The chamber was ablaze with light.会议厅里灯火辉煌。
- How to know to there is ascarid inside abdomen?怎样知道肚子里面有蛔虫？
- He was anxious about an off-and-on pain the abdomen.他因时隐时现的腹痛而焦虑。
- A catalyst is a substance which speeds up a chemical reaction.催化剂是一种能加速化学反应的物质。
- The workers'demand for better conditions was a catalyst for social change.工人们要求改善工作条件促进了社会变革。
- Experts have linked this condition to a build-up of toxins in the body.专家已把这一病症与体内毒素的积累联系起来。
- Tests showed increased levels of toxin in shellfish.检验表明水生有壳动物的毒素水平提高了。
- A vibrating membrane in the ear helps to convey sounds to the brain.耳膜的振动帮助声音传送到大脑。
- A plastic membrane serves as selective diffusion barrier.一层塑料薄膜起着选择性渗透屏障的作用。
- Don't smoke near combustible materials. 别在易燃的材料附近吸烟。
- We mustn't take combustible goods aboard. 我们不可带易燃品上车。
- Later outplant the seedlings in a replicated permanent test plantation. 以后苗木出圃栽植成重复的永久性试验林。
- The phage has replicated and the donor cells have lysed. 噬菌体已复制和给体细胞已发生裂解。