The zero point of the density scale is defined by having no specimen in the densitometer.

定义密度计内没有样品时的密度为密度尺标的零点。

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The specimen, complete with surrounding rock, had been on display for the past 50 years at a museum in Poland, but amazingly no one had spotted the footprint.

这个标本连同周围的岩石，在过去的50年里一直在波兰的一家博物馆陈列，但令人惊讶的是，从未有人发现这个脚印。

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They had no backbone and were tiny - the new specimen is only an inch long.

它们没有脊椎，体型娇小——这个新的标本只有一英寸长。

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Dr Currie said it was hard to say how long the biggest specimen was because no complete skeleton had been found.

BBC: NEWS | Science/Nature | Dino may have been pack hunter

Dr. Bour quickly concluded that the specimen came from Brazil, not Aldabra, and that gigantea was therefore no longer a valid name.

WSJ