Leaks in chemical lines or inlet plumbing indicate a possible source of air in the system.

药剂管线或进口管渗漏，可能会是系统中空气的一个来源。

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Each pattern stands for a distinct chemical element, and so different sets or patterns of spectral lines mean that the star has a different chemical composition.

每一种样式代表一种不同的化学元素，所以光谱线的不同集合或模式意味着这颗恒星有不同的化学成分。

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This light is passed through a prism, which breaks it up into a spectrum, and a unique pattern, kind of like a chemical fingerprint of spectral lines for that element appears.

铁块会一直加热，直到到达某一燃点，便会辐射出光来；而当它的光线穿过一块棱柱时，棱柱就会分割光线，形成光谱。

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Eden still lines its cans with a chemical.

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With respect to what I've said in the past around red lines -- what I've said is that the use of chemical weapons are something that the civilized world has recognized should be out of bounds.

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