摘要 : Nucleation and growth processes in colloidal crystallization of silica spheres were studied in microgravity produced by parabolic flights of an aircraft. A continuous circulating type of stopped flow cell system was used, and the ... 展开 Nucleation and growth processes in colloidal crystallization of silica spheres were studied in microgravity produced by parabolic flights of an aircraft. A continuous circulating type of stopped flow cell system was used, and the time-resolved reflection spectra were measured. The cell system is composed of a peristaltic pump, a column containing a mixed bed of ion-exchange resins and a quartz observation cell. They are connected to a PharMed tube in a closed circuit, Close-up observation with a CCD camera was made. Nucleation rates decrease in microgravity. Crystal growth rates of the face-centered cubic (fcc) lattices decrease in microgravity (0 G) by about 25% compared with those in gravity (1 G). One of the main reasons for the retardation is that the downward diffusion of spheres, which may enhance the inter-sphere collision, disappears in microgravity. No convection of the suspensions in microgravity is also important. 收起