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191.
Taku Matsuo Hiroshi Nakamura Hiroshi Sakaguchi Kouji Shimomura Isamu Yoshimatsu Keisuke Takuma 《Molecular Crystals and Liquid Crystals》2013,570(2):185-196
Remarkable electric field effects were observed with sensitized fluorescence intensities of a perylene derivative (BPDC), when rectangular AC waves (up to 10 V0-p ) were applied to nematic liquid crystal cells containing a sensitizer (C307 or AHDA) and an acceptor (BPDC) as the guest molecules. Measurements of the fluorescence lifetime of AHDA indicated that the rates of energy transfer from AHDA to BPDC were independent of the electric fields. The electric field effects completely changed the sign when the intensity variation detected at vertical direction was compared with that at the horizontal direction with respect to the liquid crystal cell. The observed electric field effects on the sensitized fluorescence were consequently suggested to come from the orientation control of transition dipole moment of BPDC through the molecular alignment of the liquid crystal. The suggestion was confirmed by the measurement of dichroic absorption of the donor-acceptor systems. 相似文献
192.
Pradip Ghosh Shunsaku Satou Takuma Tsuchiya Yasuhiko Hayashi Masaki Tanemura 《固体物理学:研究快报》2012,6(4):184-186
The direct fabrication of fully transparent conical nanocarbon structures (CNCSs) of controlled nanoscopic dimension on a flexible nafion substrate was achieved, using field electron source, by a novel room temperature ion irradiation technique. By controlling the sizes (below the wavelength of visible light) of the CNCSs, the transparency of the substrate can be tailored satisfactorily. The transparency of the CNCSs was observed to be around 90% in the visible regime depending on the ion irradiation time. Our results suggest that the direct fabrication of well controlled fully transparent CNCSs on any transparent and flexible substrate at room temperature could open a novel route for potential applications in future highly transparent, flexible (bendable), low weight and portable field emission displays (FEDs). (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
193.
Naonari Sakamoto Yutaro Hirai Tsunenobu Onodera Takuma Dezawa Yutaka Shibata Hitoshi Kasai Hidetoshi Oikawa Hiroshi Yabu 《Particle & Particle Systems Characterization》2019,36(1)
Janus particles, particles that have two distinct aspects on their surface or interiors, have attracted much attention due to their potential for application. For the application of Janus particles to high‐resolution displays, and as light sources for optical circuits and fluorescent probes, the Janus particles should be nanosize to ensure high‐resolution display and analysis, responsive to external stimuli, and highly fluorescent. However, it is still a challenging issue to develop such highly fluorescent nanoscale Janus particles and control their alignment. Magnetoresponsive Janus particles, of which the orientation can be controlled by an external magnetic field, are prepared by the simple introduction of polymer‐coated magnetic nanoparticles (NPs) into the hemispheres of Janus particles. If these magnetoresponsive Janus particles can be combined with a strong fluorescence system, then they could be ideal candidates as components of the previously mentioned applications. In the present study, Janus particles are prepared with a fluorescent dye and gold nanoparticles (Au NPs) on one side. The optical properties of the resulting particles are assessed and discussed. Furthermore, the response of composite Janus particles containing dyes, Au NPs, and iron oxide NPs to an external magnetic field is discussed. 相似文献
194.
A detailed account of various experimental techniques developed during the study on the decay rate coefficient of laser trapped 7Li atoms are presented. The frequency of a dye laser is stabilized using a simple sealed-off cell specially designed for Li vapor. The accurate number of trapped atoms are obtained by measuring the fluorescence intensity and the population ratio between the ground and the excited states by absorption coefficient measurement. The absolute value of the collisional lossrate coefficient of trapped 7Li atoms is determined by analyzing the temporal change of the fluorescence intensity when the supply of the Li beam is turned off. 相似文献
195.
196.
Yutaro Sugiura Haruya Suzuki Takuma Otomo Takaaki Miyazaki Toshiyuki Takayanagi Masanori Tachikawa 《Journal of computational chemistry》2020,41(17):1576-1585
Positron binding energies (PBEs) of 41 polyatomic molecules were calculated using the positron–electron correlation-polarization potential (CPP) approach and compared with experimentally measured values. In this approach, the short-range positron–electron potential is modeled using the density-functional expression, whereas the long-range potential is approximated by the attractive polarization potential. The positron–electron CPP model based on local-density approximation yields larger PBEs than experimental values; however, the calculated values can be substantially improved by introducing generalized gradient approximation. We also investigated the conformational dependence of PBEs for representative molecules. 相似文献
197.
Kosho Minomo Takuma Matsumoto Kazuyuki Ogata Masanobu Yahiro 《Few-Body Systems》2013,54(7-10):1417-1419
We present an accurate method of treating neutron removal reactions and it’s applications. According to the method, the nuclear and Coulomb breakup processes are consistently treated by the method of the continuum discretized coupled channels. This method is referred to as the eikonal reaction theory (ERT). We analyze the two types of removal reactions of 31Ne and 6He with ERT. 相似文献
198.
Atsushi Kawachi Takuya Teranishi Takuma Deguchi Yohsuke Yamamoto 《Heteroatom Chemistry》2013,24(1):53-57
The countercation effect on the reactivity of ambiphilic o‐(fluorodimethylsilyl)phenyl anion was investigated by replacing Li in 1 with Cu ( 4 and 5 ), Mg ( 6 ), and Zn ( 7 ). The reactivity of the aryl metal species was estimated by the yields of dimerized product 3 , which were monitored by GC. X‐ray crystallographic analysis, DFT calculations, and AIM analysis of bis(aryl)zinc 7 were performed. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:53–57, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21062 相似文献
199.
Inside Cover: Instantaneous Click Chemistry by a Copper‐Containing Polymeric‐Membrane‐Installed Microflow Catalytic Reactor (Chem. Eur. J. 48/2015) 下载免费PDF全文
200.
We report that a histidine based cationic lipid forms multi-bilayer nanotubes and the addition of metal ions such as Cu(2+) and Au(3+) induces transformation into single-bilayer nanotubes owing to coordination of the metal ions on the nanotube surface. The morphological transition was detected with X-ray scattering and electron microscopy. IR showed that the metal coordination is presumably the major driving force. The reduction of Au(3+) ions on the tube surface produced gold nanoparticles attached on the nanotube surface. The nanoparticle was almost monodisperse with the average diameter of 1.7 nm and the standard deviation σ of 0.29, which is remarkably narrower than that of previously reported lipid systems. The obtained particles were stable and no further aggregation and growth was observed after one week, providing a powerful and facile tool for producing nanoparticles in a wide range of applications. 相似文献