Some of them, such as nitrogen, oxygen, argon, neon, and so on, may be regarded as permanent atmospheric components that remain in fixed proportions to the total gas volume.

其中一些气体，如，氮，氧，氩， 氖等，作为空气的永久组成成分，总是以固定的比例存在于大气中。

youdao

For example, tax-gathering should be done at regional level, with the proceeds shared in fixed proportions, and the region, not Madrid, deciding how much goes to the town halls below it.

ECONOMIST: A survey of Spain

The boundaries between small, medium and large stocks will be set as proportions of the value of the total market, rather than as fixed dollar amounts or as an unchanging number of companies.

WSJ: The Intelligent Investor: The New Supercharged Index Funds

But a rise of such proportions would be unacceptable to the government, so the yuan is likely to remain fixed for the moment.

ECONOMIST: China's economy