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- The Pb concentrations need to be kept below 0.1% wt. 铅浓度需要保持在0.;1%25重量以下。
- The increase of Pb concentration would reduce memory curve. 铅浓度升高,记忆曲线降低。
- If not all components are lead-free the Pb concentration will increase rapidly. 如果不是所有的元件都是无铅的,则铅浓度将会快速上升。
- Pb concentration and distribution in main tree species on both sides of highway in suburbs of Nanjing City. 城郊公路两侧主要森林类型铅含量及分布规律。
- Only partial removal of the contaminated solder pot will get the Pb concentration back below 0.1% wt. 只有将被污染的焊料槽部分取下才可以让铅浓度恢复到重量0.;1%25以下。
- In Lead-free wave soldering the Cu, Fe and Pb concentrations need to be followed very closely. 在无铅波峰焊接中,需要严格遵循铜、铁和铅的浓度。
- Mycorrhizae colonization of the three species and the nodule biomass of K. striata were reduced by elevated soil Pb concentration compared to control. 与对照相比，铅污染显著降低了鸡眼草的菌根侵染率和根瘤生物量。
- Root Pb concentration in invasive S. canadensis only accounted for 6.42%, 5.93% and 11.21% of those in non-invasive K. striata under corresponding Pb treatments. 入侵种加拿大一枝黄花的根部铅浓度分别为鸡眼草各个铅处理中根部铅浓度的6.;42%25，5
- Analysis of Pb concentrations in blood was performed by graphite furnaceatomic absorption spectrometry (type AA700, Perkin Elmer, USA), and the standardized samples were friendly provided by the Center for Disease Control, USA. 美国 Perkin Elmer公司生产的AA700型原子吸收仪，血铅标准品出 美国疾病控制中心（CDC）提供。
- It's too hot to concentrate on book. 热得不能集中心思看书。
- I must concentrate my energies on decorating today. 我今天必须集中精力搞装饰。
- I can't concentrate on my work when I'm tired. 我累了就无法集中精力工作。
- Don't put me off when I'm trying to concentrate. 我正要集中注意力呢，别打搅我。
- We must concentrate our attention on efficiency. 我们必须把注意力集中在效率上。
- She couldn't concentrate on a book very long. 她不能长时间专心读一本书。
- I must concentrate upon my work now. 我现在必须集中精力工作。
- Birds concentrate (in places) where food is abundant. 鸟聚集在食物丰盛的地方。
- She felt ill. She went to work, however, and tried to concentrate. 她病了。然而她照旧去上班，并且尽力集中精神工作。
- We must concentrate our efforts on improving education. 我们必须致力於改进教育工作。
- I can't concentrate with you breathing down my neck. 你这样紧紧盯著我，使我精神无法集中。
