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461.
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Yasuo Tanaka Shohei Saito Shigeki Mori Naoki Aratani Dr. Hiroshi Shinokubo Prof. Dr. Naoki Shibata Prof. Dr. Yoshiki Higuchi Prof. Dr. Zin Seok Yoon Kil Suk Kim Su Bum Noh Jong Kang Park Dongho Kim Prof. Dr. Atsuhiro Osuka Prof. Dr. 《Angewandte Chemie (International ed. in English)》2008,47(4):614-614
463.
It is known that for any closed surface F2, every even embedding on F2 with sufficiently large representativity is 4-colorable. In this paper, we shall characterize 3-colorable even embeddings
on F2 with sufficiently large representativity. 相似文献
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The films composed of poly(L-lactide)(PLLA)/organoclay hybrids (PLACHs) have been prepared via a melt-compounding process, in which the organoclay paticles are uniformly dispersed in the PLLA matrix. The changes in PLLA crystal orientation for the uniaxially drawn films were studied by differential scanning calorimetry, X-ray diffractometry and transmission electron microscopy. Additionally, temperature dependence of the mechanical properties for these drawn films were examined by a dynamic viscoelastometer. After drawing the quenched PLACHs film at 90 °C, the orientation and crystallinity of PLLA crystal increased rapidly with increasing drawing ratio (λ) in the range more than 3 times. At the higher λ, the organoclay platelet particles in the PLACHs became parallel to the draw direction. The mechanical properties of drawn PLACHs were strongly dependent on both clay concentration and λ. 相似文献
467.
Kim DY Ahn TK Kwon JH Kim D Ikeue T Aratani N Osuka A Shigeiwa M Maeda S 《The journal of physical chemistry. A》2005,109(13):2996-2999
The excited state dynamics and two-photon absorption properties of four novel triply linked porphyrin dimers in toluene have been investigated. The fused porphyrin dimers exhibit extremely increased two-photon absorption cross-section values (12,000-15,000 GM) compared with porphyrin monomers owing to much enhanced pi-electron delocalization throughout the porphyrin dimer ring. 相似文献
468.
Highly regioselective borylation of 5,15-diaryl- and 5,10,15-triarylporphyrins has been achieved by the reaction with bis(pinacolato)diborane under iridium catalysis. Borylated porphyrins are a useful building block for constructing porphyrin arrays, hence offering an effective route to beta-functionalized porphyrins. 相似文献
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