You need a substance and then that substance has to have a property that changes depending on the heat flow, i.e., depending on whether it's sensing that it's the same temperature or different temperature than something else.

你需要某种物质,它的某种性质,随着热量的流动而改变，也就是说,依赖于它是否感觉到它,与其他的物体处于相同的温度。

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The e-mail security firm Postini confirms that the flow of spam e-mail that it tracks and blocks--between six and eight billion messages a week--hasn't decreased since Soloway's arrest.

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We also performed other traditional corporate valuation techniques (i.e. discounted cash flow, comparable companies, leveraged buyout).

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Of course he wants to learn about new products, but he also goes to hear industry gossip on talent flow--e.g.

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