http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
A FULL CHARGE SEPARATION OVER THE TWO SAME CHROMOPHORES IN A PHOTOSYNTHETIC TETRAD
Osuka, Atsuhiro,Marumo, Shinji,Okada, Tadashi,Taniguchi, Seiji,Mataga, Noboru,Ohno, Takeshi,Nozaki, Koichi,Yamazaki, Iwao,Nishimura, Yoshinobu Korean Society of Photoscience 1997 Journal of Photosciences Vol.4 No.3
The synthesis and excited-state dynamics are described for a tetrad (ZC - ZP - ZP - I) consisting of zinc chlorin (ZC), zinc porphyrin (ZP), zinc porphyrin (ZP), and pyromellitimide (I), which upon photoexcitation provides a fully charge-separated state (ZC$^+$- P - ZP - l$^- $) with lifetimes of 230 $\mu$s in THF and > 50$ \mu$s in DMF at room temperature via a stepwise electron-transfer relay that has been detected by the ps-time resolved transient absorption spectroscopy.
Innentitelbild: Hexaphyrin Fused to Two Anthracenes (Angew. Chem. 39/2012)
Naoda, Koji,Mori, Hirotaka,Aratani, Naoki,Lee, Byung Sun,Kim, Dongho,Osuka, Atsuhiro WILEY‐VCH Verlag 2012 Angewandte Chemie Vol.124 No.39
<P><I>π</I>‐expandierte Porphyrinoide in denen aromatische Strukturteile an den Porphyrinring kondensiert sind, rücken zunehmend in den Blickpunkt. In ihrer Zuschrift auf S. 9994 ff. berichten D. Kim, A. Osuka et al. über die Bildung eines Hexaphyrins, das mit zwei Anthracenylsubstituenten oxidativ kondensiert wurde. Das rechteckige konjugierte System verleiht dem kondensierten Hexaphyrin eine bemerkenswerte rotverschobene und eine ungewöhnlich scharfe Q‐Banden‐ähnliche Absorption bei 1467nm. (Photos: kyoto‐design.jp)</P>
Excitation Energy Migration in Multiporphyrin Arrays
황인욱,Atsuhiro Osuka*,김동호,Naoki Aratani 대한화학회 2005 Bulletin of the Korean Chemical Society Vol.26 No.1
During the last decade, the exploration of nanoscale device and circuitry based on molecules has gained increasing interest. In parallel with this, considerable effort is being devoted to the development of molecular photonic/electronic materials based on various porphyrin arrays. This involves light as an input/output signal and excitation energy migration as a mechanism for signal transmission. Absorption of a photon at the light collector end of the porphyrin array yields the excited state, which migrates among the intervening pigments until reaching the emitter, whereupon another photon is emitted. As a consequence, it is relevant to understand the excitation energy transfer (EET) processes occurring in various forms of porphyrin arrays for the applications as artificial light harvesting arrays and molecular photonic/electronic wires. Since the excitonic (dipole) and electronic (conjugation) couplings between the adjacent porphyrin moieties in porphyrin arrays govern the EET processes, we have characterized the EET rates of various forms of multiporphyrin arrays (linear, cyclic, and box) based on various time-resolved spectroscopic measurements. We believe that our observations provide a platform for further development of molecular photonic/electronic materials based on porphyrin arrays.
Aratani, Naoki,Kim, Dongho,Osuka, Atsuhiro Wiley (John WileySons) 2009 Chemistry, an Asian journal Vol.4 No.8
<P>Recent progress in the synthesis of covalently linked porphyrin arrays with large two-Photon absorption (TPA) cross-section values has been reviewed with a particular focus on the relation of TPA properties with molecular structures. Covalently linked porphyrin arrays continue to be important and useful for the creation of functional materials owing to their chemical robustness, fine-tuning, and easy manipulation. More importantly, the porphyrin electronic systems are quite susceptible to periphery conjugative perturbations, hence allowing facile fabrications to extensively delocalized systems. This property has been used for exploration of porphyrin-based molecular systems with large TPA values, demonstrating a general trend that enhancement in electronic interactions leads to large TPA cross-section values. As a representative example, the porphyrin tapes exhibit larger TPA values owing to the fully delocalized nature of the pi-electrons. This Focus Review will help understand the structural requirements of porphyrin arrays with large TPA values, which will be useful for future applications in optical communication in the IR region.</P>
An Educational Methodology for Sustainable Development
Kazutoshi Fujihira,Koichi Osuka 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8
It is required to solve various environmental and social problems and achieve ‘sustainable development (SD).’ Education is critical for promoting SD. Here we approach ‘education for sustainable development (ESD)’ from the viewpoint of ‘control.’ First, we show the control system for SD, identifying necessary elements such as controlled objects, controlled variables and control objectives. Next, we provide a methodology of ESD, showing the procedure forcreating educational programs as well as the educational elements that such programs should contain. Moreover, we present a case study, whose results have confirmed the validity of this methodology.
Möbius aromaticity and antiaromaticity in expanded porphyrins
Yoon, Zin Seok,Osuka, Atsuhiro,Kim, Dongho Nature Publishing Group 2009 Nature chemistry Vol.1 No.2
<P>Aromaticity is a key concept in chemistry, dating back to Faraday's discovery of benzene in 1825 and Kekule's famous alternating-double-bond structure of 1865. In 1858, the Mobius strip was discovered by Mobius and Listing. The Huckel rules for predicting aromaticity, stating that [4n + 2] pi electrons result in an aromatic system, work for planar molecules. Although molecules with Mobius geometry are not found in nature, chemists have tried to synthesize such molecules since the first theoretical prediction by Heilbronner in 1964 and the prediction of Mobius aromaticity for suitable compounds with [4n] pi electrons. However, Mobius-aromatic molecules have proved difficult to synthesize, and sometimes even to identify. Here we summarize recent contributions of several research groups that have succeeded in synthesizing Mobius-type molecules. The results of this survey lead us to suggest that the generation of Mobius topologies in expanded porphyrins is easier than hitherto appreciated.</P>