When observing the Cu-Zn-Al alloy, which has been treated in mixed acid and etching reagent in normal temperature and pressure, a nanotube in novel structure and shape is found. It is a single-wall nanotube with smooth surface,on which there is basically no absorbate. It is verified through transmission electron microscope (TEM) that the dislocation lines are observed on the nanotube. Structural analysis reveals that the mechanics of nanotube generation is in relation to"quasi-fluid state" that exists in the alloy. The solid "quasi-fluid state" is the research result of Mr. Gao and his colleagues over ten years. It is a new material that exists besides gas, liquid, solid, and liquid crystal.