The results showed that to maintain environment in which high and low DO occur alternately is the key to achieving short-cut nitrification.

试验结果表明，保持高、低溶解氧交替的环境是实现短程硝化的关键；

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Study was made on the conditions in which short-cut nitrification was achieved and on the variation of sludge characteristics at low DO in SBR and CSTR.

研究了低溶解氧(DO)下，在SBR和CSTR反应器内实现短程硝化的条件及其污泥性状的变化。

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The COD, ammonia and total nitrogen (TN) removal efficiency were studied in the paper at low DO concentration in a pilot-scale A/O nitrogen removal plant treating domestic wastewater.

应用A/O中试装置处理实际生活污水，研究了低DO浓度下系统对有机物、氨氮和总氮的去除效果。

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In addition,some low-income areas do not have enough supermarkets where people can buy fresh and healthy foods.

VOA: special.2010.06.07

What I'm going to ask you to do Andrew Low is to help me develop ways to improve the Andrew Low course.

你们的任务就是,探索改进,课程的新方法。

麻省理工公开课 - 媒体、教育、市场课程节选

So do you think noble gases would have a high positive electron affinity, a low positive, or negative electron affinity?

那么，你认为稀有气体的电子亲和能,应该是一个高的正值，一个低的正值，还是一个负值？

麻省理工公开课 - 化学原理课程节选

The passengers in the aeroplane flying low overhead do not pay for the disturbance the engine noise causes on the ground.

ECONOMIST: Taxes for a cleaner planet

Of course, the new long-term projects are not viable, whatever the financial models may indicate: artificially low rates do not create any additional savings with which to construct them.

FORBES: Gold Mining Stocks Are An Increasingly Attractive Opportunity

And when immigrants working for low wages do put downward pressure on natives' wages, they may raise the (real) wages of natives in general by keeping prices lower than they otherwise would be.

ECONOMIST: Workers of the world | The