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Sauce glazed wares of Yaozhou kilns are famous for their high gloss and distinctive glaze color palette varying from yellowish‐brown to reddish‐brown. In this work, sauce glazes were successfully replicated using the traditional technology of Yaozhou kilns. Micro‐Raman spectroscopy, combined with optical microscopy, scanning electron microscopy, x‐ray fluorescence, and reflective spectroscopy, was systematically applied to analyze the chemical composition, nature and distribution of crystals, and the coloration of the glazes. The results show that the yellowish‐brown glaze is mainly original from dendritic ε‐Fe2O3 crystals, whereas the reddish‐brown color is mainly derived from dendritic hematite crystals. Such dendritic structure could account for slightly color variations of the glaze surface observed in different angles, which also reported in Japanese Bizen ceramics. The principal component analysis (PCA) was further applied to study the Raman spectra of these iron oxides. The PCA results effectively indicates the structural disorders of these crystals introduced by ion substitutions. These substitutions could not only stabilize the crystals but also darken the crystals color. Besides, high Mg in the raw materials was found to benefit the growth of magnesioferrite crystals. The relative low level of Fe2O3, high level of SiO2, and CaO may relate to the formation of ε‐Fe2O3 crystals. [ABSTRACT FROM AUTHOR]

The fiber reinforced polymer is popularly applied for structural reinforcement and, however, usually suffers from long-term environmental effects, for example exposed to the ultraviolet radiation, alternating changes of moist-heat, and submerged in water chronically. As a result, the material aging and structural performance degradation are inevitable, which could eventually lead to the deterioration of mechanical behavior of fiber reinforced polymer, hence the attenuation or failure of repaired structures. It is very expensive and time consuming to use the experimental method to find out the aging patterns of fiber reinforced polymer. For fiber reinforced polymer with different volume fraction, the upper and lower limit of elastic modulus can be deduced by the energy principle. Combining this theory with tests, a semi-empirical deteriorating method can be used to analyze the change of fiber reinforced polymer mechanics behavior. And a series of empirical coefficients, determined by natural aging tests, are introduced. The coefficients are applied in the revised formula for the prediction of mechanics behaviors of fiber reinforced polymer. The elastic modulus of deteriorating fiber reinforced polymer is influenced by the fiber, the resin matrix, and the volume fraction of the fiber. For different fiber volume fraction, the experimental test is not the unique way to assess the durability of fiber reinforced polymer, as long as the laws of fiber aging, the laws of resin aging, and the fiber volume fraction are already known. The proposed model shows good agreement with the test results, hence can be used to predict the elastic modulus of aging fiber reinforced polymer, which can be utilized as references for engineering design and research in the future. [ABSTRACT FROM AUTHOR]