ABSTRACT
Berry et al. (1-3), Moisar and Klein (4), and Claes and Berendsen (5) developed a unique method for preparation of monodisperse particles of silver bromide (AgBr) and silver chloride (AgCl), called controlled double-jet precipitation, as characterized by simultaneous introduction of silver nitrate and corresponding halide solutions into a gelatin solution at a precisely regulated rate. In the double-jet process, very fine primary nuclei or embryos are generated in a domain of the gelatin solution where these reactant solutions are injected. In the meantime, the primary nuclei are dispersed into the bulk solution region where relatively large stable nuclei grow at the expense of the smaller unstable nuclei by Ostwald ripening (6). Thus, in this open system, a nucleation zone and a bulk zone for particle growth coexist in the same solution throughout the precipitation process, as shown in Fig. 4.1.1, where the small circles and the larger cubes represent the primary nuclei of AgBr and the stable nuclei, respectively.
