Theoretical analysis emphasizes on heat transfer both inside propellant and between igniter exhaust and internal grain surface.

理论分析着重研究了点火燃气与推进剂表面传热及推进剂内瞬态热传导规律。

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This machine solves problem of leveling grain surface with large size, realizes the intention of leveling grain surface and saving time.

该平整器解决了大粮面平整的难题，实现了使整体粮面平整如镜和节省工时的设计初衷。

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The study indicates that the end of flame spread over grain surface corresponds to Max value of pressure rise rate and the flame is not continuous in fin slots.

研究表明，火焰传播结束时刻对应于燃烧室升压速率极大值，尾部翼槽内火焰传播过程不连续。

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Armstrong began to describe what he saw: "The surface appears to be very, very fine grain,like a powder.

VOA: special.2009.07.15

Visually these boards have a washboard effect-and as the varied grain intersects the wood surface and light at different angles, a hologram-type depth emerges.

NPR: Excerpt: 'A Splintered History Of Wood'

"We're finding that when you rub a natural biological surface that has an orientation - that has a grain, if you will - and you run that grain perpendicularly to the long axis of the ridges, we find a dramatic increase in friction, " Dr Dominy told BBC News.

BBC: Artificial finger tests evolutionary origin of prints

There was no visible wood grain in the print, and its shape indicated it was taken from a curved surface, not a flat one.

BBC: Fingerprint evidence is fallible