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221.
Takeshi Fukuda Kouji Fujimoto Mauro M. Murakami Kenji Kawabata Takeaki Miyamoto 《Macromolecular Symposia》1996,101(1):147-155
Three co-operative phenomena that are supposed to originate in the orientation-dependent interactions among polymer segments are discussed and attempted to be interpreted in terms of a common set of polymer models. 相似文献
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Yutaka Moritomo Kouhei Yonezawa Takeaki Sakurai Takeshi Yasuda Yasuo Takeichi Hayato Kamioka 《Molecular Crystals and Liquid Crystals》2015,620(1):32-37
Clarification of the morphology of bulk heterojunction (BHJ) is indispensable for true comprehension of the organic solar cells. Here, we performed scanning transmission X-ray microscopy (STXM) for a poly-(9,9-dioctylfluorene-co-bithiophene) (F8T2)/[6,6]-phenyl C71-butyric acid methyl ester (PC71BM) blend film annealed at various temperatures (Tan). We found that the fullerene concentration within the polymer-rich domain decreases with Tan while the domain size (~230 nm) is essentially unchanged. We will discuss the interrelation between the film morphology and the photovoltaic performance. 相似文献
227.
Hatsumi Nakazawa Shinobu Fujinami Miho Motoyama Takao Ohta Takeaki Araki Hajime Tanaka 《Molecular Crystals and Liquid Crystals》2013,570(1):871-878
Abstract Polymerization-induced phase separation in polymer-dispersed liquid crystal is studied by computer simulations in two dimensions. The domain morphology resulting from phase separation is investigated by solving the couple set of equations for the local volume fraction and the nematic order parameter, taking into account the viscoelastic effects and gelation due to polymerization. Comparing the morphology of phase separation by temperature quench, it is shown that the viscoelastic effects and gelation enable the polymer-rich phase to form a stable interconnected domain even when the polymer component is minority. 相似文献
228.
Takuto Ohsato Dr. Yuri Okuno Prof. Dr. Shintaro Ishida Prof. Dr. Takeaki Iwamoto Dr. Ka‐Ho Lee Prof. Dr. Zhenyang Lin Prof. Dr. Makoto Yamashita Prof. Dr. Kyoko Nozaki 《Angewandte Chemie (International ed. in English)》2016,55(38):11426-11430
A potassium diboryllithate (B2LiK) was synthesized and structurally characterized. DFT calculations, including NPA and AIM analyses of B2LiK, revealed ionic interactions between the two bridging boryl anions and Li+ and K+. Upon standing in benzene, B2LiK deprotonated the solvent to form a hydroborane and a phenylborane. On the basis of DFT calculations, a detailed reaction mechanism, involving deprotonation and hydride/phenyl exchange processes, is proposed. An NBO analysis of the transition state for the deprotonation of benzene suggests that the deprotonation should be induced by the coordination of benzene to the K+. 相似文献
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We study some counting and enumeration problems for chordal graphs, especially concerning independent sets. We first provide the following efficient algorithms for a chordal graph: (1) a linear-time algorithm for counting the number of independent sets; (2) a linear-time algorithm for counting the number of maximum independent sets; (3) a polynomial-time algorithm for counting the number of independent sets of a fixed size. With similar ideas, we show that enumeration (namely, listing) of the independent sets, the maximum independent sets, and the independent sets of a fixed size in a chordal graph can be done in constant time per output. On the other hand, we prove that the following problems for a chordal graph are #P-complete: (1) counting the number of maximal independent sets; (2) counting the number of minimum maximal independent sets. With similar ideas, we also show that finding a minimum weighted maximal independent set in a chordal graph is NP-hard, and even hard to approximate. 相似文献
230.
Nakakoshi M Ueda M Sakurai S Asakura K Utsumi H Miyata O Naito T Takahashi Y 《Magnetic resonance in chemistry : MRC》2007,45(11):989-992
Direct observation of the unstable intermediate in the radical addition reaction of the oxime ether 1 mediated by triethylborane (Et(3)B) is described using (1)H and (11)B micro channeled cell for synthesis monitoring (MICCS), which was recently developed as an interfacing microchip for NMR. It was possible that the signal of the intermediate was observed as a result of using MICCS technique with a standard NMR instrument. This result supports the structure of the intermediate analyzed by diffusion-ordered spectroscopy (DOSY) NMR method in a previous paper. The procedure of micro channeled cell for synthesis monitoring-nuclear magnetic resonance (MICCS-NMR) was much easier than that of DOSY method. It was proven that it could be applied to the reaction in an anhydrous condition. 相似文献