水下通气管

With a snorkel, however, a diver can stay under water for quite a long time

可是，潜水员携带一根通气管就可以在水下呆很长时间。

A swimmer with a snorkel can still breathe, but notice that snorkelers float right on the top. Were they to try sinking underneath, even a moderate amount, the same thing would happen.

一个游泳的人带着通气管仍然可以呼吸，但是需要注意这个通气管必须浮在水上，他们尝试沉入水下，甚至是适当很深的水，相同的事情将会发生。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。