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121.
Scipioni R Hill JP Richards GJ Boero M Mori T Ariga K Ohno T 《Physical chemistry chemical physics : PCCP》2011,13(6):2145-2150
We present a structural and electronic inspection of reduced pyrazinacenes within the DFT framework. Our analysis provides a clear indication that compounds in which reduced pyrazine rings are well separated from each other are rather stable. Conversely, if the reduced pyrazine rings approach each other or cluster together, the compounds become increasingly unstable. The tautomers analyzed are likely to possess properties suitable for application as proton transport materials due to protic isomerism processes. On the basis of our findings, we propose that protic transport should occur through a concerted proton transfer without involving intramolecular aggregation of the dihydropyrazine groups. Furthermore, the electronic structure analysis shows that this class of compounds can be classified as small bandgap semiconducting materials, possessing even metallic character depending on the tautomeric structure, and with potential nanotechnological applications in molecular electronics and fuel cells. 相似文献
122.
In molecular dynamics simulations single-domain ferroelectric water is produced under ordinary ambient conditions utilizing carbon nanotubes open to a water reservoir. This ferroelectric water diffuses while keeping its proton-ordered network intact. The mobile/immobile water transitions and the step-wise changes in net polarization of water are observed to occur spontaneously. The immobile water becomes mobile by transforming into the single-domain ferroelectric water. Our general notion of relating a more highly ordered structure with a lower temperature has so far restricted researchers' attention to very low temperatures when experimenting on proton-ordered phases of water. The present study improves our general understanding of water, considering that the term 'ferroelectric water' has so far practically stood for 'ferroelectric ice,' and that single-domain ferroelectric water has not been reported even for the ice nanotubes. 相似文献
123.
Shinozaki J Nakane T Onodera N Takano A Masuda K 《Chemical & pharmaceutical bulletin》2011,59(6):767-769
Lactucenyl acetate (1), a new member of migrated lupane triterpenoids was isolated from Lactuca indica and its structure was elucidated on the basis of spectral analyses. The structure of tarolupenyl acetate was revised as lup-19(21)-en-3β-yl acetate (2). 相似文献
124.
We have calculated 7Li(K ?, K +) reaction spectrum at ${p_{K^-} = 1.65}$ GeV/c and ${\theta_{K}^{+} = 0^\circ}$ within the framework of distorted wave impulse approximation (DWIA) using the ${[\Xi^-{-}^6{\rm He}(0^+)]-[\Xi^-{-}^6{\rm He}^*(2^+)]}$ coupled-channel Green’s function approach, and examined whether the peak corresponding to the Ξ ? hypernuclear states can be visible in the reaction spectrum, by employing various Ξ ??6He effective potentials. 相似文献
125.
126.
Shinichi Yamabe Tsutomu Minato Teruyuki Watanabe Takahisa Machiguchi 《Theoretical chemistry accounts》2011,130(4-6):981-990
The title reactions were investigated experimentally and theoretically. The benzyne--tropone pair has been known to give a Diels?CAlder [4+2] cycloadduct. However, in the present experiment using two sources of benzyne, many unexpected products were obtained. In particular, a zwitterion with a C?CCl bond is strikingly a major product, the structure of which was determined by the X-ray analysis. The bond is formed by quenching the Cl atom from the solvent CH2Cl2, which demonstrates that the reactions proceed via radical processes. DFT calculations revealed the elementary processes of the reactions. The presence of the novel zwitterion in the solid state has been interpreted in terms of the permanent dipole?Cdipole attractions/interactions/stabilization. 相似文献
127.
128.
Hiroko Kominami Takahisa Yamasaki Yoichiro Nakanishi Kazuhiko Hara 《Journal of luminescence》2012,132(12):3100-3102
In this study, the detailed crystallization mechanism of SrGa2S4: Eu2+ thin film phosphors annealed by Nd:YAG laser (355 nm) was examined. Using the spectral transmittance measurements of SrS and Ga2S3 thin films, the influence of temperature on SrGa2S4 thin film formation by laser irradiation was investigated using the thermal conducting equation. From the calculation, it is thought that Ga2S3 absorbed greater laser energy than SrS and generated the heat. By diffusing heat throughout the thin film, crystallization was promoted. 相似文献
129.
Watanuki T Machida A Ikeda T Aoki K Kaneko H Shobu T Sato TJ Tsai AP 《Physical review letters》2006,96(10):105702
The phase study of a Cd-Yb 1/1 approximant crystal over a wide pressure and temperature range is crucial for the comparison study between periodic and quasiperiodic crystals. The Cd(4) tetrahedra, the most inner part of the atomic clusters, exhibited various structural ordering in the orientation sensitive to pressure and temperature. Five ordered phases appeared in a P-T span up to 5.2 GPa and down to 10 K. The propagation direction of ordering alternated from [110] to <111> to at about 1.0 GPa and again to [110] at 3.5-4.3 GPa. The primarily ordered phases that appeared by cooling to 210-250 K between 1.0-5.2 GPa further transformed to finely ordered ones at 120-155 K. Besides the original short-range type interaction, a long-range type interaction was likely developed under pressure to lead to the primary ordering of Cd(4) tetrahedra. Coexistence of these interactions is responsible for the complicated phase behavior. 相似文献
130.
Chie Hosokawa Suguru N. Kudoh Ai Kiyohara Yoichiroh Hosokawa Kazunori Okano Hiroshi Masuhara Takahisa Taguchi 《Applied Physics A: Materials Science & Processing》2008,93(1):57-63
An all-wet femtosecond laser microprocessing technique was utilized for patterning and cutting functional network of living
neuronal cells on a multi-electrode dish (MED). The neuronal cells cultured on a source substrate were transferred onto an
electrode in a MED probe in solution by utilizing a femtosecond laser-induced impulsive force and a pattern of neuronal cells
were formed on the MED probe. The cellular activity of the detached neurons was supported that neurites could be regenerated
around the electrodes. As another processing method, the neurons stretching between electrodes were selectively cut by the
direct femtosecond laser irradiation and the spontaneous electrical activity of the neuronal network was evaluated. While
the spontaneous action potentials of neurons were synchronized before the cutting, the synchronization disappeared after the
cutting, indicating that the neuronal network is locally disconnected by the laser cutting. The present method is applicable
to artificial reconstruction of living neuronal network. 相似文献