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1.
Rational Molecular Design towards Vis/NIR Absorption and Fluorescence by using Pyrrolopyrrole aza‐BODIPY and its Highly Conjugated Structures for Organic Photovoltaics
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Prof. Dr. Soji Shimizu Taku Iino Prof. Dr. Akinori Saeki Prof. Dr. Shu Seki Prof. Dr. Nagao Kobayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2893-2904
Pyrrolopyrrole aza‐BODIPY (PPAB) developed in our recent study from diketopyrrolopyrrole by titanium tetrachloride‐mediated Schiff‐base formation reaction with heteroaromatic amines is a highly potential chromophore due to its intense absorption and fluorescence in the visible region and high fluorescence quantum yield, which is greater than 0.8. To control the absorption and fluorescence of PPAB, particularly in the near‐infrared (NIR) region, further molecular design was performed using DFT calculations. This results in the postulation that the HOMO–LUMO gap of PPAB is perturbed by the heteroaromatic moieties and the aryl‐substituents. Based on this molecular design, a series of new PPAB molecules was synthesized, in which the largest redshifts of the absorption and fluorescence maxima up to 803 and 850 nm, respectively, were achieved for a PPAB consisting of benzothiazole rings and terthienyl substituents. In contrast to the sharp absorption of PPAB, a PPAB dimer, which was prepared by a cross‐coupling reaction of PPAB monomers, exhibited panchromatic absorption across the UV/Vis/NIR regions. With this series of PPAB chromophores in hand, a potential application of PPAB as an optoelectronic material was investigated. After identifying a suitable PPAB molecule for application in organic photovoltaic cells based on evaluation using time‐resolved microwave conductivity measurements, a maximized power conversion efficiency of 1.27 % was achieved. 相似文献
2.
Li-Ngee Ho Tasuku Ikegawa Hiroyasu Nishiguchi Katsutoshi Nagaoka Yusaku Takita 《Applied Surface Science》2006,252(18):6260-6268
A synthesis of molybdenum incorporated mesoporous aluminophosphate with long-chain n-alkylamine as template material had been prepared under non-aqueous condition. These materials were extensively characterized by using X-ray diffraction (XRD), nitrogen sorption isotherms, nuclear magnetic resonance of 27Al and 31P (NMR), inductive coupled plasma (ICP), electron spin resonance (ESR), Fourier transform infrared (FTIR) and thermogravimetric-differential thermal analysis (TG-DTA). Morphology of the materials had been observed by using transmission electron microscope (TEM) that revealed the mesoporous materials possessed wormhole-like structures. Alkaline solvent extraction using n-butylamine/ethanol had been efficiently removed the n-alkylamine from the mesoporous samples which yielded BET surface areas around 550-730 m2/g. BJH analysis showed a narrow pore size distribution which increased with increasing of the carbon chain length of alkylamine (template). Valence state and coordination of the molybdenum in the obtained samples were investigated by using ESR and FTIR where it was found that Mo4+ and Mo6+ molybdenum species existed in the molybdenum incorporated mesoporous aluminophosphate in tetrahedral coordination. 相似文献
3.
J. Fujimoto T. Ishikawa M. Jimbo T. Kaneko T. Kon Y. Kurihara M. Kuroda Y. Shimizu Y. Yasui 《Pramana》2007,69(5):943-946
We report the recent development on the SUSY calculations with the help of GRACE system. GRACE/SUSY/1LOOP is the computer
code which can generate Feynman diagrams in the MSSM automatically and compute one-loop amplitudes in the numerical way. We
present new results of various two-body decay widths and chargino pair production at ILC (international linear collider) at
one-loop level.
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Cellulose derivative resin (CDR) suspensions containing resin particles of cellulose nitrate (CDR(CN)), cellulose acetate (CDR(CA)), or cellulose triacetate (CDR(CTA)) were prepared as the sorbent for resin suspension injection (RSI) electrothermal atomic absorption spectrometry (ETAAS), in which fine resin particles holding a desired trace element were directly injected into the graphite tube as the suspension. To compare the sorption ability, the distribution ratios of the Mo(VI)-phenylfluorone complex were measured between the aqueous phase and the sorbents, including the CDRs mentioned above and the finely divided anion exchange resin (AR). The results showed that the sorption ability decreases in the following order: CDR(CN) > or = AR > CDR(CA) > or = CDR(CTA). It was concluded that CDR(CN) was able to extract more than 98% of Mo(VI), and was suitable for RSI-ETAAS as well as AR. CDR(CN) was used for the determination of Mo in NIES certified reference materials, No. 10 Rice flour-unpolished; the results showed fairly good agreements between the analytical values and the certified values. 相似文献
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A. Noda S. Nakamura Y. Iwashita S. Sakabe M. Hashida T. Shirai S. Shimizu H. Tongu H. Ito H. Souda A. Yamazaki M. Tanabe H. Daido M. Mori M. Kado A. Sagisaka K. Ogura M. Nishiuchi S. Orimo Y. Hayashi A. Yogo S. Bulanov T. Esirkepov A. Nagashima T. Kimura T. Tajima T. Takeuchi K. Matsukado A. Fukumi Z. Li 《Laser Physics》2006,16(4):647-653
In order to widely spread out particle beams utilized in cancer therapy, laser-produced ions are developed as the injection beam for an ion synchrotron dedicated for cancer therapy. Such a laser ion source is expected to contribute largely to the realization of compactness of the size and low cost of the cancer therapy accelerator. The energy spectrum of the laser-produced ions, however, has no peak, but their intensities decrease exponentially according to the increase of the energy. For the purpose of modifying such a situation, we have proposed a scheme to rotate the beam in the longitudinal phase space with the use of the RF electric field, which is phase-adjusted with the pulse laser. We aim for a reduction of the energy spread of ± 5% selected by an energy analyzer and slits to ±1% by such phase rotation. For this purpose, a quarter wavelength resonator with two gaps with the same resonant frequency as the source laser has already been fabricated, together with its RF power source. The above phase rotation system and its recent experimental realization are presented. 相似文献
9.
Hiroyasu Nishiguchi Hiroshi Yamada Masaru Ogura Tatsumi Ishihara Yusaku Takita 《Research on Chemical Intermediates》2003,29(7-9):755-760
The oxygen storage capacity of CeO2, Ce0.9Pr0.1O2, Pt?Rh/CeO2 and Pt?Rh/Ce0.9Pr0.1O2 was investigated by conventional GC pulse method and transient pulse techniques. It is shown that incorporation of PrOy into CeO2 matrix strongly promotes oxygen storage capacity (OSC) measured using the transient pulse technique. The improvement of OSC at low temperature is observed in Pt?Rh loaded onto CeO2 and Ce?Pr catalysts. 相似文献
10.
Hiroyasu Sato 《应用有机金属化学》1991,5(4):207-219
This is meant to be a brief overview of the developments of research activities in Japan on organometallic compounds related to their use in electronic and optoelectronic devices. The importance of organometallic compounds in the deposition of metal and semiconductor films for the fabrication of many electronic and opto-electronic devices cannot be exaggerated. Their scope has now extended to thin-film electronic ceramics and high-temperature oxide superconductors. A variety of organometallic compounds have been used as source materials in many types of processing procedures, such as metal–organic chemical vapor deposition (MOCVD), metalorganic vapor-phase epitaxy (MOVPE), metal–organic molecular-beam epitaxy (MOMBE), etc. Deposited materials include silicon, Group III–V and II–VI compound semiconductors, metals, superconducting oxides and other inorganic materials. Organometallic compounds are utilized as such in many electronic and optoelectronic devices; examples are conducting and semiconducting materials, photovoltaic, photochromic, electrochromic and nonlinear optical materials. This review consists of two parts: (I) research related to the fabrication of semiconductor, metal and inorganic materials; and (II) research related to the direct use of organometallic materials and basic fundamental research. 相似文献