Organizing of magnetic skyrmions shows several forms similar to atomic arrays of solid states.Using Lorentz transmission electron microscopy, we report the first direct observation of a stable liquid-crystalline structure of skyrmions in chiral magnet Co 8.5 Zn 7.5 Mn 4 (110) thin film, caused by magnetic anisotropy and chiral surface twist. Elongated skyrmions are oriented and periodically arranged only in the <110> directions, whereas they exhibit short-range order along the <001> directions, indicating smectic skyrmion state. In addition, skyrmions possess anisotropic interaction with opposite sign depending on the crystal orientation, in contrast to existing isotropic interaction.

WC-SiC whisker ceramics (5 vol% SiC) containing Cr 3 C 2 and/or V 8 C 7 with no metallic binders were prepared by resistance-heated hot pressing at 1650 C and were examined with regard to sinterability, microstructure and mechanical properties. The addition of Cr 3 C 2 or V 8 C 7 brought about an increase or decrease in the sinterability. For equal molar amounts of Cr and V, V 8 C 7 more strongly inhibited the growth of WC grains than Cr 3 C 2 . The hardness of the ceramics was dependent on the WC grain size which was influenced by the nature or quantity of the additives. The hardness values are consistent with the Hall-Petch-type relationship between hardness and WC grain size estimated for WC phases in WC-Co cemented carbides.

Thermoelectric properties (Thermoelectromotive force and electrical conductivity) of porous silicon carbide ceramics are evaluated. Porous silicon carbide ceramics are made from rice hull by reacting silica and carbon, both of which are included in rice hull, using hotpressing method[1].When nitrogen gas is used as enviromental gas for hotpressing, this material becomes n-type semiconductor. It shows comparably high themoelectromotive force. Thermoelectric properties of this material change with the processing conditions.The relationship between thermoelectric properties and microstructure is also evaluated.

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