1,3-Bis(2-pyrryl)benzene was used to prepare dibenziamethyrin, in which two pyrrole units of [24]amethyrin(1.0.0.1.0.0) are replaced by benzene. 1,4-Bis(2-pyrryl)benzene, 2,5-bis(2-pyrryl)thiophene, and 4,4'-bis(2-pyrryl)biphenyl were also used in place of 2,2'-bipyrrole to give expanded analogues of [24]rosarin(1.0.1.0.1.0) and [32]octaphyrin(1.0.1.0.1.0.1.0). These large porphyrinoids can incorporate multiple metal units of Rh(CO)2 and Pd(π-allyl) with considerable deviation of the metal atoms from the dipyrrin planes, evidenced by X-ray crystallography. The coordinated Rh(CO)2 group shuttled between both sides of the macrocycle; the rate was dependent on the spacer, ring size, and number of metal atoms. Variable temperature (1) H NMR spectroscopy showed that the tris-rhodium complexes of the expanded rosarins with 1,4-phenylene or 2,5-thienylene spacers adopt a C3v -symmetric form and a Cs -symmetric form as a result of the Rh(CO)2 groups hopping through the macrocycle cavity. The C3v -symmetric form has a greater dipole moment and, therefore, is favored in solvents of greater polarity. The Rh(CO)2 groups in the tris-rhodium complex of the expanded rosarin with 4,4'-biphenylene spacers hop so fast that an averaged spectral pattern (D3h ) was seen in the (1) H NMR spectrum, even at -60 °C. Expanded octaphyrins with 1,4-phenylene and 2,5-thienylene spacers bind four Rh(CO)2 groups outside the macrocycle cavity to form a D2d -symmetric saddle-shaped structure that did not show any dynamic behavior on the NMR timescale, even at 80 °C. This tetranuclear complex is one of the largest porphyrinoid metal complexes characterized by X-ray crystallography to date.

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On the basis of Ti-vacancy defect compensation mode, highpermittivity La-and Ce-doped barium titanate ceramics (BLTC) with perovskite structure, i.e., (Ba 1Àx La x )(Ti 1Àx/4Ày Ce y )O 3 , where x 5 0.01-0.05 and y 5 0.05, were prepared by conventional ceramic processing techniques. Dielectric characteristics, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and hysteresis loops were measured. Defect chemistry and diffuse phase transition (DPT) in BLTC are discussed. Co-doping with the relatively smaller La 31 ions at Ba sites and the relatively larger Ce 41 ions at Ti sites in the BaTiO 3 host lattice resulted in a fine-grained microstructure (0.8-1.1 lm), marked raising, and broadening of the Curie peak characteristic of DPT. The Curie temperature (T C ) at 800 Hz decreased rapidly at a dramatic rate of À301C/ at.% La when y 5 0.05. By means of co-doping with La and Ce, this is the first time that high k ''Y5V'' ceramics (BLTC: 0.03rxr0.04, y 5 0.05) with e 0 RT 410 000 over a frequency range of 1-100 kHz have been achieved in rare-earth-doped BaTiO 3 ceramics. J ournal

In the northern part of East Asia, forests dominated by larch are extensively distributed and probably play an important role in the global carbon cycle. However, a knowledge of the CO2 balance of larch forests based on long‐term flux measurements is very restricted in East Asia. Thus, a long‐term flux measurement has been started in 2000 at a larch plantation on a flat terrain in Hokkaido, Japan to obtain more information on the CO2 and energy balances of larch forests. From September 2000 to August 2001 the net ecosystem CO2 exchange (NEE) changed seasonally in accordance with the annual cycles of phenology and climate. NEE was negative for six months of the growing season, May–September; the larch ecosystem was a carbon sink with a peak intensity of –0.38 mol m−2 d−1 for this period. In the leafless season from November to April the forest ecosystem was a carbon source with an intensity ranging between 0 and 0.05 mol m−2 d−1. Annual NEE from September 2000 to August 2001 was −24.4 to −32.4 mol m−2 yr−1 (=−293 to −389 gC m−2 yr−1); this value is compatible with those reported from other temperate forests. Annual evapotranspiration for the same period was 367 mm, which was only 29% of annual precipitation.