The composition of water requires oxygen and hydrogen.

水的组成需要氧和氢。

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Scientists already knew how the composition of water varies throughout the country.

科学家已经知道全国各地水的成份变化情况。

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The chemical composition of water remains constant whether it is in solid, liquid or gaseous state.

无论处于固态、液态或气态，水的化学成份都保持不变。

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On average, the composition of Holstein milk is 87.7 percent water, 3.7 percent milk fat and 8.6 percent skim solids.

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Instead, differences in composition between warm-water and cold-water ion channels were the result of a phenomenon called RNA editing, in which special enzymes alter the structure of the RNA messenger, and thus of the final protein.

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In addition to a sea floor mapping project, the researchers will make chemical analyses of water samples that will help them determine the temperature, salinity and composition of a strong circumpolar current that flows around the boundary of the Arctic Ocean.

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