然后针对现役静态混合器的缺点提出了优化后的结构，包括三大类：一、不同叶片组间距的静态混合器；

Then, the optimized structure was put forward in view of the active static mixers' shortcomings, including three major categories: 1, the static mixers with different distance between blade groups;

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陶艺被分为三大类——陶器、炻器和瓷器——包括器皿，屋顶瓦片等建筑制品，以及模型物体和造像。

The ceramics fall into three broad types—earthenware, stoneware, and porcelain—for vessels, architectural items such as roof tiles, and modeled objects and figures.

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所有的生命形式可以划分为三大类：真核生物(包括植物，动物，真菌，以及其他生物)、细菌以及古生菌。

All of life can be divided into three domains: Eukarya (including plants, animals, fungi, and other organisms) Bacteria, and Archaea.

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