The main spiral staircase depicts a rhythmic ribbon that ascends to attic space.

主旋转楼梯像一条螺旋上升的缎带将空间引向顶楼。

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The spiral ribbon is made of two layers. That is, theinner ribbon makes the material move outwards, while the external ribbon makes the material moveinwards which forms a good circrlation of material.

螺旋叶片一般做成二层外层螺旋将物料从两侧向中央汇集内层螺旋将物料从中央向两侧分流使物料在混合槽内形成对流混合从而达到高均匀度混合。

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Wavy, ribbon and curly grain are byproducts of spiral grain that reverses itself periodically as a tree grows to produce a thing called interlocked grain.

NPR: Excerpt: 'A Splintered History Of Wood'