由放射性钠衰变产生正电子，冷却后形成一个由大约100万个正电子组成的体积同样大小的粒子云团，这团正电子被存放在相邻的一个容器中。
The positrons, produced by the decay of radioactive sodium, are cooled into a similarly sized cloud of around 1m particles and held in a neighbouring trap.
这些所有形成外立面的材料是由回收的砖块组成，位于侧面的内部螺旋形的走廊是由混凝土定制设计而成。
Materials consist of both recycled traditional bricks, which form the exterior facade, and custom designed concrete screen blocks, which flank the interior spiral passageway.
沉积岩不像火成那样是由熔融的岩石物质形成，沉积岩是由早先存在的浆岩、变质岩和沉积岩的矿物碎屑及岩石屑组成的。
Unlike igneous rocks which are formed from molten rock material, sedimentary rocks are made up of particles of previously existing rocks, including igneous, metamorphic and sedimentary rocks.
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