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  • Today, we are going to talk about nanotechnology.

  • When we say something is nano, we mean it is very small.

  • The size of one nanometer is one billionth of a meter

  • which is about 100,000 times smaller than the width of a human hair.

  • Making new things at this incredibly small scale is called

  • nanotechnology and it's one of the most exciting and fast moving

  • areas of science today.

  • Some nanomaterials are naturally occurring, you can find them everywhere,

  • in volcanic ash, ocean spray, fine sand and dust.

  • Naturally occurring nanostructures are also present in plants and animals.

  • For example, nanostructures in insect eyes ensure an anti-reflection

  • and water repelling effect so they can fly safely.

  • Nowadays, scientists can create nanostructure themselves,

  • by rearranging the atoms of an object, they can make

  • new nanomaterial with new properties.

  • For example, that are stronger, lighter or different in colour.

  • Properties change also according to their size

  • and this is the magic of the technology.

  • In the food area, researchers are working with nanotechnologies

  • to create novel products that may be of benefit to health and diet.

  • For example, nanosilver has antibacterial properties that can be used

  • in food contact material such as cutting boards.

  • In food supplements, nanosized carriers increase absorption of nutrients.

  • Nanosensors can be incorporated into packaging to monitor the quality

  • and shelf life of food from manufacturers to consumers.

  • It can also make food ingredients tastier or healthier.

  • Carving up a grain of salt into small nanosized grains

  • increases it's surface area significantly.

  • This means that your food needs far less salt to be equally tasty.

  • This is good news for those who like crackers but are worried

  • about their blood pressure.

  • We need to make sure that food nanotechnologies

  • do not cause harm to consumers.

  • This is why in the EU, engineered nanomaterials in food

  • require a safety assessment.

  • There are specific properties that need to be taken into account

  • when assessing impact on human health and the environment.

  • And this is where EFSA comes in.

  • Over the coming years, nanotechnology will touch the lives of all of us.

  • Like many scientific advances, it brings uncertainty and potential risks.

  • It is up to scientists, business and governments

  • to make it work.

Today, we are going to talk about nanotechnology.

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A2 初級 美國腔

什么是纳米技术(What is nanotechnology?)

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    joey joey 發佈於 2021 年 04 月 24 日
影片單字