Cover illustration

December 28, 2004; 101 (52)
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Cover image: Wavy, low-angle grain boundary in the mineral olivine. Running from upper left to lower right, the boundary separates regions of crystal rotated by -0.75° (green) to +0.75° (red). Yellow dots along the boundary mark dislocations that accommodate grain misorientation. The nanostructure of such boundaries influences many solid-state physical and chemical phenomena. See the article by Johnson et al. on pages 17936–17939. Photograph courtesy of Craig L. Johnson, Martin J. Hÿtch, and Peter R. Buseck.

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December 28, 2004; 101 (52)
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