photographic negative

基本解释

An apparatus for measuring the optical density of a material, such as a photographic negative.
比如人口密度就是指單位麪積的人口數量。
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The fish collagen has special application in the photographic negative, the biological material and food industry.
魚膠原蛋白在照相底片，生物材料和食品行業有特殊的應用。
The book bears the same relations to the traditional texts as a photographic negative does to a print:the areas of darkness and light have been reversed.
本書與那些傳統歷史書籍的關系猶如照相底片與相片的關系，暗區與亮區被顛倒了過來。