BRR

基本解释

The CI-340 portable photosynthesis system of CID was used to study the photosynthetic characteristics of Callistemon rigidus R. Br.
采用CI-340便携式光合作用测定系统，研究红千层的光合特性。
The hysteretic loops of the models of these two kinds of structures are obtained. Based on the test results and analysis, the design method for strengthening R. C. frame with exterior br…
依据对试验结果的分析，得出了多层内框架房屋采用外加钢筋混凝土壁柱加固内框架与采用外加构造柱加固砖墙的抗震设计计算方法。
The effects of several plant pesticides on tobacco diseases and pests were studied in field during 2002-2004. The results indicated that Veratrum nigrum L. , Macleaya cordata (Willd. ) R. Br.
2004年通过田间试验研究了几种植物源农药对烟草病虫害的防治效果。

So if we want to talk about the volume of that, we just talk about the surface area, which is 4 pi r squared, and we multiply that by the thickness d r.
如果我们要讨论它的体积，我们要用的是表面面积，也就是４πｒ的平方，乘以厚度ｄｒ
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We're saying the probability of from the nucleus in some very thin shell that we describe by d r.
某一非常薄的壳层dr内,一个原子的概率,你想一个壳层时。
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And we reasoned that these two eventually reach some kind of an equilibrium separation which we are using lowercase r to represent.
我们推导,这两个最终能达到,某种平衡分离,我们用小写的r代表。
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