However, it is unclear whether these positrons can escape from the stellar debris in sufficient quantity to explain the size of the observed cloud.

然而，尚不清楚是否有足够数量的正电子能够逃离恒星残骸以解释观察得到云团的大小。

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A number of studies have observed that a product's production costs decline by some quantity about each time cumulative output doubles.

许多研究表明一种产品每当其产品的累积产量翻番时，它的生产成本的数量将下降。

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When this quantity exceeds 2.2 theory indicates the existence of a sharp pressure peak which has not been observed experimentally.

当这个量超过2.2时，理论表明存在陡急的压力尖峰，而这压力尖峰尚未在实验中观察到。

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