Mosaic Structure of Photographic Emulsion Crystals
CRYSTAL imperfections play an important part in present studies of the formation of the photographic latent image. In large silver bromide crystals it has been shown1 that silver prints out along individual dislocation lines. Little direct evidence has yet been given on defects within the small grains of photographic emulsions, since neither light microscopy nor electron microscopy has yet proved effective in this field.
Oriented attachment of particles: 100 years of investigations of non-classical crystal growth
The results of investigations of non-classical crystal growth by the oriented attachment mechanism are summarized. The data published since the end of the 19th century are considered, the attention being focused on analysis of publications of the last 15 years. Data on characteristic features of the oriented attachment of particles are described systematically. The experimental methods used to elucidate the peculiarities of non-classical crystal growth, including in situ methods, are discussed. The prospects of application of the oriented attachment of particles for the formation of various materials are demonstrated. The bibliography includes 227 references.
A New X‐Ray Diffraction Method for Studying Imperfections of Crystal Structure in Polycrystalline Specimens
A new double spectrometer method for the study of polycrystalline materials is developed. From intensity data of the diffracted spots and known angular settings of the specimen, the angular range of reflection of the misaligned scattering regions in a crystallite is determined statistically.The instrument and the technique of the multiple exposure method is described. The statistical evaluation of the data is discussed and a mathematical treatment introducing correction terms as functions of the azimuth and of the Bragg angle is presented.A commercial silicon powder specimen was investigated. The average angular range of reflection was found to be nearly the same for all (hkl)‐reflections with exception of (111), (333), and (444).The study of broadening effects with the same instrument has been started.The new double spectrometer method for polycrystalline specimens described in this paper is based on the examination of numerous microscopic spots reflected by individual crystallites. The small spots on th...