граница
см. тж. внешняя граница; на границе фаз; на границах зёрен
• We should establish a strict line of demarcation (or dividing line) between mechanics' work and the work of mechanics' helpers.
• The dashed line indicates the demarcation (or boundary) between these two regions.
Источник:
Русско-английский научно-технический словарь
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