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1.
Inside Cover: Photoinduced Formation of an Azobenzene‐Based CD‐Active Supramolecular Cyclic Dimer (Chem. Eur. J. 18/2015)
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2.
Dr. Yogesh Kumar Maurya Dr. Pingchun Wei Takahide Shimada Dr. Kazuhisa Yamasumi Dr. Shigeki Mori Prof. Dr. Ko Furukawa Dr. Hajime Kusaba Prof. Dr. Tatsumi Ishihara Prof. Dr. Yongshu Xie Dr. Masatoshi Ishida Prof. Dr. Hiroyuki Furuta 《化学:亚洲杂志》2021,16(7):743-747
A facile synthetic strategy towards conformationally stable chiral chromophores based on dimeric porphyrinoids has been established. A peculiar class of face-to-face intramolecularly interlocked corrole dimers were formed by the oxidative C−C coupling linked at the inner carbon sites upon simple treatment of copper(II) ions. Their intrinsic electronic structures were modulated by the peripheral corrole ring annulations, which lead to distinct optical properties and redox profiles. The stereogenic carbon centers implemented in the confused corrole skeleton provided a rationale for designing novel chiral materials. 相似文献
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4.
Curved Ferroelectric Liquid Crystal Matrix Displays Driven by Field-Sequential-Color and Active-Matrix Techniques 总被引:1,自引:0,他引:1
Hideo Fujikake Hiroto Sato Takeshi Murashige Yoshihide Fujisaki Taiichiro Kurita Tadahiro Furukawa Fumio Sato 《Optical Review》2006,13(1):14-19
This paper describes a curved field-sequential-color matrix display using fast-response ferroelectric liquid crystal. Black
matrix and transparent electrode patterns were formed on a thin plastic substrate by a transfer method from a glass substrate.
While a composite film of liquid crystal and micro-polymers of walls and fibers was formed between the flexible substrates
by printing, laminating and curing processes of a solution of monomers and liquid crystal, the mechanical stability was enhanced
by use of multi-functional monomers to form large display panels. The image pixels of the matrix panel were driven by an active
matrix scheme using an external switch transistor array at a frequency of 180 Hz for intermittent three-primary-color backlight
illumination. The flexible A4-paper-sized color display with 24 × 16 pixels and 60 Hz field frequency was demonstrated by
illuminating it with sequential three-primary-color lights from light-emitting diodes of the backlight. Our display system
is useful in various information displays because of its freedom of setting and location. 相似文献
5.
Yong Lee Kazuhiko Hosomi Hiroyuki Uchiyama Toshio Katsuyama Shinya Kominami Tomoyoshi Mishima 《Optical Review》2003,10(1):38-42
An InGaAsP slab-type asymmetric-coupled-waveguide-based dispersion compensator with a mode selector has been designed and fabricated. The mode selector is necessary to select either a symmetric [with a positive group-velocity dispersion (GVD)] or antisymmetric (with a negative GVD) supermode. These supermodes exist simultaneously in the dispersion-compensation region of the device. Pulse-compression experiments were used to test the dispersion compensator, evaluating the function of the mode selector. A theoretical study of the experimental results shows that the mode selector obtains a very strong selectivity (nearly 100%) for the antisymmetric supermode. 相似文献
6.
H. Sunaoshi Y. Fukashiro M. Furukawa M. Yamauchi S. Hayashibe T. Shinozuka M. Fujioka I. Satoh M. Wada S. Matsuki 《Hyperfine Interactions》1993,78(1-4):241-245
The ground state hyperfine splitting of87Sr+ was measured with a precision of 1×10–8. The experiments were performed with an RF ion trap connected to an ISOL (isotope separator on-line), where all the possible transitions between Zeeman sublevels were observed by a laser-microwave double resonance method. The magnetic dipole hyperfine constant was determined to beA=–1 000 473.673 (11) kHz. 相似文献
7.
Yoshinori Nishiwaki Masahiko Shimoyama Toshio Nakanishi Toshio Ninomiya Izumi Nakai 《Analytical sciences》2006,22(10):1297-1300
Total reflection X-ray fluorescence spectrometry (TXRF) has been applied for trace elemental analysis of small glass fragments. A small glass sample (a fragment with weight less than 0.5 mg) was decomposed by 100 microg of HF/HNO3 acid; the material was condensed to 10 microl and was dried on a Si wafer. Since the size of the dried residue on the Si wafer was less than 1 cm in diameter, an incident X-ray beam with about 1 cm in width could effectively excite elemental components in such a small glass fragment. The precision of the present technique was checked by analyzing the glass fragments (<0.5 mg) from NIST SRM612; the relative standard deviations (RSD) of less than 8.1% were achieved for elemental ratios that were normalized by Sr. Fragments (<0.5 mg) obtained from 23 figured sheet glasses were used as samples for estimating the utility of this technique to forensic discrimination. Comparison of five elemental ratios of Ti/Sr, Mn/Sr, Zn/Sr, Rb/Sr, and Pb/Sr calculated from X-ray fluorescence spectra was effective in distinguishing glass fragments that could not be differentiated by their refractive indexes (RI). 相似文献
8.
Yamada Kaoru Matsutani Shigeaki Uchiyama Akira Takahashi Toshio 《Journal of inclusion phenomena and macrocyclic chemistry》1991,11(1):49-54
Analyses of crown ether complexes of alkali metal ions and characterization of the complexes formed inm-nitrobenzyl alcohol have been carried out by fast atom bombardment (FAB) mass spectrometry. By using m-nitrobenzyl alcohol as a matrix for measurements, the stoichiometry of the complexes was assessed on the basis of the observed FAB peaks. In addition, the formation of crown ether-alkali metal complexes at a 2 : 1 molar ratio was enhanced by increasing the ionic radius of the metal ion in agreement with previous observations. On these grounds, FAB mass spectrometry may provide a rapid means for investigation of the complexation behavior of crown ethers and the stoichiometry of the complexes. 相似文献
9.
10.
The average heat transfer rates were measured for natural convection of air in a shallow cylindrical enclosure heated from below and cooled from above in a bore space of an inclined super-conducting magnet. Depending on the location of the enclosure in the bore space, the angle of inclination and the strength of magnetic field, the net acceleration force could be arbitrarily varied and in this report, two locations where mostly axial magnetizing force prevails were selected. The average heat transfer rates varied with the angle of inclination due to the change in the total net acceleration of gravitational and magnetizing forces. Numerical computations were also carried out for the similar system under the combined magnetizing and gravitational forces and the computed average Nusselt numbers agreed mostly with the measured results. Detailed flow modes were graphically presented for the computed cases. 相似文献