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Characteristics of atomic ordering and TiO 6 octahedron tilting boundaries of Pb 1 m x Ca x TiO 3 (x ” 0.5) were studied using electron diffraction and transmission electron microscopy in the present work. Pb 0.5 Ca 0.5 TiO 3 specimens exhibit 1/2(100), 1/2(110) and 1/2(111) extra reflections regularly in electron diffraction patterns. However, chemical ordering behavior may not be able to explain absence of some diffraction sports. Dark field images show types of different image characteristics using extra reflections of 1/2(111) as well as 1/2(100) and 1/2(110), implying different origins of the super-reflections. An octahedron-tilting scheme was considered to interpret diffraction behavior and wavy boundaries in Pb 1 m x Ca x TiO 3 materials. Contrast characterstics of microstructural features and adjacent matrix indicate that the wavy lines are attributed to the boundaries of octahedron-tilting domains.

The ordering of Ba(Zn1/3Ta2/3)O3 is altered by A-site substitution of La or K. The ordering behavior is studied using X-ray diffraction, electron microscopy, and Raman spectroscopy. Ba1-x La x (Zn(1-+x)/3Ta(2-x)/3)O3 shows a transformation from 1:2 to 1:1 ordering with the increasing La content. Ba1-x K x (Zn(1-x)/3Ta(2-x)/3)O3 displays a monotonous decrease in 1:2 order with the K content. The ordered domains of BLZT first shrink in size with x, then transform into 1:1 ordered domains, and the sizes of new domains increase with x again. The effect of ordering on the quality factor of BLZT is discussed.

The so‐called coke layer collapse phenomenon was observed on a blast furnace top model which was 1/4‐scale of No. 2 blast furnace of China Steel. A simulation program based on the Bishop simplified method of soil mechanics and the material balance was developed to identify the collapse occurrence and to predict the burden distribution after the collapse. A close agreement between the experimental results and the prediction of simulation program was found.

Upper and lower reciprocal variational principles have been used to estimate the effective conductivity (or diflusivity)across beds of randomly dispersed fibers with orientations distributed in two and three dimensions. Estimated thermal conductivities of fiber glass insulation, graphite-epoxy fiber reinforced composite materials, as well as the diffusivities of several fibrous materials agree well with measured values.