Every substance, no matter what it is, is composed of very small particles called molecules.

各种物质，不论它是什么，都是由一些称为分子的很小的粒子构成的。

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At the moment, such ink is composed of small, transparent spheres containing black and white particles suspended in a clear fluid.

目前的墨水是由悬浮在液体中的小的透明装有黑色和白色粒子的球体所构成。

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Nanoscience is the science of small particles of materials and is one of the most important research frontiers in modern technology.

纳米科学是一门研究物质细小微粒的科学，它已经成为现代科技中最重要的前沿研究领域之一。

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And if silver is turned into very small particles, it has antimicrobial properties that are not present in the bulk material.

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The trick here is that these particles are very, very small, which means they're essentially all surface.

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As plastic is a petroleum based product these small particles act as persistent organic polluters, which means that they form a sponge attracting toxins such as insecticides and pesticides.

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