Plate-like particles of Ca 3 Co 4 O 9 have been prepared in which Bi and Na were partially substituted for Ca to improve the thermoelectric performance. Successfully fabricated dense and highly textured ceramics have been obtained by combining the templated grain growth technique (TGG) with hot-pressing (HP). Ca 3 Co 4 O 9 single crystals, which have alternating layers of Co-O and Ca-Co-O in the direction of the c-axis, show high electrical conductivity along the layer compared with that across the layer. Hence, a highly oriented TGG 1 HP specimen showed high electrical conductivity compared with the specimen sintered under uniaxial pressure (UP 1 PLS). The improved electrical conductivity with high Seebeck coefficient of the highly oriented specimen (TGG 1 HP) gave a high thermoelectric power factor of 5.9 6 10 24 W m 21 K 22 at 1073 K. The figures-of-merit at 773 K and 1073 K were calculated to be 8.54 6 10 25 K 21 (ZT ~0.066 at 773 K) and 1.69 6 10 24 K 21 (ZT ~0.18 at 1073 K), respectively. These values are quite high among Ca-Co-O polycrystalline systems reported so far.

A novel family of azobenzene-based photochromic amorphous molecular materials has been created. They were found to readily form amorphous glasses with well-defined glass-transition temperatures and to exhibit photochromism as amorphous films as well as in solution. It was found that their quantum yields of trans-cis photoisomerization were smaller as amorphous films than in solution and that the backward cis-trans thermal isomerization reactions as amorphous films were either accelerated or retarded relative to those in solution, depending upon their molecular structures. In addition, the rate acceleration for the cis-trans thermal isomerization as amorphous films relative to solution was found to be more prominent as the irradiation time for generating the cis-isomer became shorter.

In order to evaluate the role of granivorous mice, Apodemus speciosus Temminck and Apodemus argenteus Temminck, in the regeneration of Pasania edulis (Makino) Makino, an evergreen tree, we conducted field studies examining acorn crops, the population dynamics and hoarding behavior of mice and pre‐ and postdispersal acorn predation in an evergreen broad‐leaved forest dominated by P. edulis in Kagoshima, southern Japan. The study was conducted from 1994 to 2000. Apodemus mice selected sound acorns and hoarded them in the soil after transporting them for distances ranging from 5.4 to 19.9 m. This behavior appeared to be beneficial to the establishment of seedlings of P. edulis. However, the positive effects were negated by a high rate of recovery of the acorns hoarded by the mice. A life‐table analysis of five cohorts of P. edulis indicated that postdispersal predation of acorns by Apodemus mice was a major contributor to annual variation in the number of new seedlings. A considerable number of acorns germinated only in years with a good acorn crop and a low level of resident mice. These results suggest that Apodemus mice are serious acorn predators rather than important dispersers. After germination, acorns were attacked by the acorn borer at a high rate. From these results, we can conclude that acorn production probably makes a smaller contribution to the regeneration of P. edulis than coppice shoot production at the study site.

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A novel family of photochromic amorphous molecular materials based on dithienylethene, 1-(5-{4-[bis(4methylphenyl)amino]phenyl}-2-methylthiophen-3-yl)-2-(2methylbenzo[b]thiophen-3-yl)-3,3,4,4,5,5-hexa¯uorocyclopentene (1o) and 1,2-bis(5-{4-[bis(4-methylphenyl)amino ]phenyl}-2-methylthiophen-3-yl)-3,3,4,4,5,5-hexa¯uorocyclopentene (2o) with glass-transition temperatures of 66 and 94 ³C, respectively, has been developed. Comparison of photochromic properties between 1o and 2o shows that the incorporation of two bulky triphenylamine moieties leads to higher conversion of photocyclisation in the amorphous ®lm.