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- The average trend over 1980 to 1990 is about 13 ppbv year part per billion by volume year. 1980至1990的平均增长速度是每年13ppbv十亿份之一体积。
- According to the state Department of Public Health, bromate levels should reach at least 200 parts per billion before adverse health effects are seen. 链接出处根据KNBC引用DPH的数据，bromate的含量至少要到200才会对人体有害。
- Data are presented as concentrations in part per billion (ppb) or qualitatively as positive or negative, depending on results reported. 数据作为部分的浓度每10亿（浓度）或定性为积极或消极的，取决于报告的结果。
- Data are presented as concentrations in part per million (ppm), part per billion (ppb) or qualitatively as positive or negative, depending on results reported. 数据作为部分的浓度为每百万（百万分之一），每10亿部分（浓度）或定性为积极或消极的，取决于报告的结果。
- Early in previous interglacial intervals, the methane concentration typically reached a peak of almost 700 parts per billion (ppb) as precession brought summer radiation to a maximum. 先前的间冰期早期，夏季辐射由于岁差而达到最大值时，通常甲烷浓度也到达高峰，约700ppb（ppb为十亿分之一）。
- The test method for determining residual vinyl chloride monomer content in parts per billion level in PVC resin by capillary column gas chromatography headspace technique is suggested. 提出用大口径毛细管顶空进样气相色谱法对聚氯乙烯树脂中十亿分之一级残留氯乙烯含量的测量方法。
- To date, at least 157 houses in D.C. have lead levels at the tap higher than 300 parts per billion (ppb), and thousands more have exceeded the Environmental Protection Agency's limit of 15 ppb. 到目前为止，华府至少有157户住家的自来水铅含量高过300ppb（1ppb为10亿分之一），另有数千户的含铅量超过美国环保署规定的上限15ppb。
- " The sensitivity of modern analytical apparatus has lowered some detection thresholds past parts per million, down to parts per billion. 现在的分析设备的灵敏度已经降低了一些检测限，高至百万分率，低至十亿分率。
- parts per billion 十亿分之几,10 亿分率
- parts per billion (ppb) 十亿分率
- parts per billion concentration PPB浓度
- Salinity of 32 parts per thousand. 盐度32零件‰ 。
- part per billion 十亿分之 ...; 十亿分之一
- Your ear can pick up sound waves from air pressure changes as small as one part per ten billion. 你的耳朵可以从空气气压的几百亿分之一的变化中提取出声波。
- In the sea water sampled the salinity is two parts per thousand. 在取样的海水中,盐度为千分之二。
- Oceanic salinity generally has a range from 34 to 37 parts per thousand. 海洋中海水的盐度通常为34‰－37‰。
- Only three parts per million can kill sea urchin embryos, for example. 废水处理不能完全清除其最常用的成分三氯生，而它对海洋生物有毒。
- Alloy steel heats are vacuum-treated on degassing units to reduce hydrogen contact to less than two parts per million and reduce metallic oxides. 合金钢热是在脱气装置下进行真空处理，以将氢接触减少到百万分之二以下，并减少金属氧化物。
- The term parts per million(ppm) was widely used but frequently led to misinterpretation. 广泛使用百分之几（ppm）表示结果，但常常引起误解。
- What are your lead numbers typically on this product? Do you offer a product with lead under 250 parts per million? 你们的典型产品的导数是什么?你们提供每百万250个配件用这个导数的产品吗?
