The gold concentrated with poly-urethane foam was roasted by adding Ni to obtain a stable recovery of gold in ppb Level.

以泡塑富集金、以镍盐作基体改进剂，提高了金的回收率和稳定性。

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The Breast Cancer Fund collected 2 samples of 6 different types of food marketed to children, and found levels of BPA ranging from 21 parts per billion (PPB) to 77.5 PPB, with an average of 49 PPB.

乳腺癌基金会选取了六种面向儿童市场的食物，并各抽取了两个样本进行研究。研究结果发现这些食物中双酚含量范围为十亿分之二十一到十亿分之七十七点五，平均含量为十亿分之四十九。

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Abstract: the existence of chlorophenol compounds in water volume reaches PPB concentration that there will be a stench.

摘要：氯酚类化合物在水中的存在量达到ppb浓度时即会出现明显的恶臭味。

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In 2011, concentrations reached a new high of 1813 parts per billion (ppb), 259% higher than pre-industrial levels.

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And in the prohibition zone, up to 2, 799 ppb is allowed.

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Emissions of nitrous oxide -- 40% of which are estimated to come from human activity -- reached 324.2 ppb, up one ppb on the 2010 figure and 120% higher than pre-industrial times.

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