磁场环境中卤化银微晶体的制备

设计了一种动态磁场处理方式,研究了该方式下磁场对单注法制备卤化银微晶体的大小及分布的影响。SEM照片以及粒径分布曲线表明,未经磁化的卤化银微晶体平均粒径为285．3nm,在磁场环境中制备的卤化银微晶体平均粒径为126．8nm,而且颗粒分布均匀,晶粒分散状态良好。分析了明胶以及溶液中离子在磁场中受到的作用,认为在磁场作用下,正、负离子具有互相分离的趋势,同时磁场作用改变了明胶大分子在溶液中的状态,二者的共同作用使得制备的晶粒具有更小的粒径。根据舒卡洛夫公式以及聚合物对胶体熵稳定作用理论,讨论了磁处理和未磁处理之间的差异。提出的磁处理方式能够有效影响明胶中卤化银的结晶过程,这可能为控制胶体中颗粒的大小及分布提供新思路。

The Preparation of Silver Halide Micro-crystals in Magnetic Fields

A kind of dynamic magnetic configuration has been designed, and the effect of the magnetic treatment on the preparation of silver micro-crystal by single jet method has been studied. SEM photographs and size distribution curves showed that silver halide micro-crystal with magnetic treatment was more sizable and better-dispersed particles with the average diameter of 126, 8nm, while that without magnetic treatment was agglomerated particles with the average diameter of 285. 3nm. Mechanism analysis of crystallization processes indicates that the increase of the viscosity of gelatin and the supersaturating degree of the solution after magnetic treatment has been combined to produce silver halide micro-crystal of smaller size. Meanwhile based on the theory of entropy-stabilized effect of polymer, we suggest that the increase of the viscosity of gelatin also help to produce better-dispersed crystals.