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1. Influence of grain boundary energy anisotropy on the evolution of grain boundary network structure during 3D anisotropic grain growth

   https://doi.org/10.1016/j.commatsci.2022.111879  

   Niño, José D. ; Johnson, Oliver K. ( January 2023 , Computational Materials Science)
2. Simultaneous Extraction of the Grain Size, Single-Crystalline Grain Sheet Resistance, and Grain Boundary Resistivity of Polycrystalline Monolayer Graphene

   https://doi.org/10.3390/nano12020206  

   Park, Honghwi ; Lee, Junyeong ; Lee, Chang-Ju ; Kang, Jaewoon ; Yun, Jiyeong ; Noh, Hyowoong ; Park, Minsu ; Lee, Jonghyung ; Park, Youngjin ; Park, Jonghoo ; et al ( January 2022 , Nanomaterials)

   The electrical properties of polycrystalline graphene grown by chemical vapor deposition (CVD) are determined by grain-related parameters—average grain size, single-crystalline grain sheet resistance, and grain boundary (GB) resistivity. However, extracting these parameters still remains challenging because of the difficulty in observing graphene GBs and decoupling the grain sheet resistance and GB resistivity. In this work, we developed an electrical characterization method that can extract the average grain size, single-crystalline grain sheet resistance, and GB resistivity simultaneously. We observed that the material property, graphene sheet resistance, could depend on the device dimension and developed an analytical resistance model based on the cumulative distribution function of the gamma distribution, explaining the effect of the GB density and distribution in the graphene channel. We applied this model to CVD-grown monolayer graphene by characterizing transmission-line model patterns and simultaneously extracted the average grain size (~5.95 μm), single-crystalline grain sheet resistance (~321 Ω/sq), and GB resistivity (~18.16 kΩ-μm) of the CVD-graphene layer. The extracted values agreed well with those obtained from scanning electron microscopy images of ultraviolet/ozone-treated GBs and the electrical characterization of graphene devices with sub-micrometer channel lengths. 

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3. Secondary Ion Mass Spectrometry Methodology for Isotopic Ratio Measurement of Micro‐Grains in Thin Sections: True Grain Size Estimation and Deconvolution of Inter‐Grain Size Gradients and Intra‐Grain Radial Gradients

   https://doi.org/10.1111/ggr.12247  

   Jones, Clive ; Fike, David A. ; Meyer, Katja M. ( December 2018 , Geostandards and Geoanalytical Research)

   In a thin section, grains that were approximately sphericalin situappear circular in cross section, and the distribution of apparent diameters frequently assumed to be their size distribution. Scanning ion imaging by secondary ion mass spectrometry (SIMS) is capable of providing precise (< 1‰) stable isotope ratio measurements of such grains, but, importantly, also registers their rate of evolution in apparent size as they are ablated by the primary beam. By assessing rates of radius change with depth, the described methodology enables the ‘true’ size of grains to be estimated, as well as the distance of the sectioned surface from the original grain centre. Transects in three dimensions are made possible, and this capability enables better identification (and thus separation) of both inter‐grain chemical signatures as a function of grain size, and intra‐grain radial trends. In this example, we highlight the specific application to pyrite (FeS₂) minerals, which are frequently analysed bySIMSto determine their inter‐grain and intra‐grain geochemical variations, particularly in their sulfur stable isotopic ratios (δ³⁴S). Benefits of the new methodology over the Faraday cup ‘spot mode’ are described. Data correction algorithms and precision considerations are discussed.

    

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4. Grain rotation and coupled grain boundary motion in two-dimensional binary hexagonal materials

   https://doi.org/10.1016/j.actamat.2021.117583  

   Waters, Brendon ; Huang, Zhi-Feng ( February 2022 , Acta Materialia)
5. Relationship between grain boundary segregation and grain boundary diffusion in Cu-Ag alloys

   https://doi.org/10.1103/PhysRevMaterials.4.073403  

   Koju, R. K. ; Mishin, Y. ( July 2020 , Physical Review Materials)

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