Edges, deep recesses and secondary surfaces are not included in the significant surface.

边缘、深隐窝和次表面并不包含在正表面中。

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If gypsum is adopted as the face layer because the surface is smooth and flat secondary surface-rolling procedure for surface can be omitted.

若采用石膏作面层，其光洁平整的表面可以省去表面的二次抹平工序。

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When such damage comes to the surface of steel and rust occurs, the surface shall be cleaned by power tools to the secondary surface preparation grade and coated as originally painting scheme.

如果钢表面发生上述损坏，产生锈，用电力工具对表面进行清除，处理至二次表面处理等级，涂上一层与原始油漆一样的涂层。

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Equal in excellence to the 264-seat main theater but presenting a striking design contrast, this secondary screening room has a hot pink entrance and features exposed loudspeakers and a grey, perforated acoustical wall and ceiling surface, making it more of an exposed machine for the moving image.

ENGADGET: Museum of The Moving Image plans multi-million dollar updates with HD, 3D