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Time:2015.11.16
Image reproduction or transmission is used to visually record information and express ideas and a means of perception, such as painting, oil painting, photography, copy and printin…
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Time:2015.12.29
1. What is light? The light emitted from the light emitter (source) out of the electromagnetic wave. Visible light is electromagnetic waves that can be perceived by the human e…
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Time:2015.12.29
  Barrier properties strength function Water and gas …
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Time:2015.12.29
1, viscous Winding printed ink layer is attached to a contact surface (usually on the back of the film), thereby preventing the occurre…
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