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1.
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
3.
In this study we examined the unsteady and chaotic characteristics of the natural convection field in vertical slots at large
Prandtl number. In the computation, temperature dependence of viscosity was partially taken into consideration. As a result
we discovered that the spatial region where a significant temperature fluctuation is detected corresponds to the spatial region
where the secondary cells exist. The largest Lyapunov exponents calculated from the temperature on the center line have a
local maximum at the lower region of the enclosure when the viscosity change was considered. These characteristics agree well
with the experimental ones that have been observed by authors (Ishida, Kure and Kimoto 2001). 相似文献
4.
Shuichi Ishida Keiki Takeda Atsushi Okamoto Ichiro Shibasaki 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):255
Magnetoresistance (MR) effects have been investigated in perpendicular and parallel magnetic fields at 300, 80 K and liquid He temperatures for undoped InSb thin films 0.1–2.3 μm thick grown on GaAs(1 0 0) substrates by MBE. At high temperatures, the intrinsic carriers show the parabolic negative MR observable only in magnetic fields parallel to the film. The skipping-orbit effect due to surface boundary scattering in the classical orbits in the plane vertical to the film has been argued to be responsible for the negative MR. At low temperatures (T=80 K), the transport is dominated by the two-dimensional (2D) electrons in the accumulation layers at the InSb/GaAs(1 0 0) hetero interface; MR is positive and shows a logarithmic increase with anisotropy between parallel and perpendicular field orientation, arising from the 2D weak anti-localization (WAL) that reflects the interplay between the spin-Zeeman effect and strong spin–orbit interaction caused by the asymmetric potential at the interface (Rashba term). The zero-field spin splitting energy of Δ013 meV, the electron effective mass of m*0.10m0 seven times of the band edge mass in bulk InSb and the effective g-factor of |g*|15 in the accumulation layer have been inferred from fits of MR for the 0.1 μm thick film to the 2D WL theory. 相似文献
5.
Takayuki Yaegashi Shinya Yodoya Masahiko Nakamura Hiroki Takeshita Katsuhiko Takenaka Tomoo Shiomi 《Journal of polymer science. Part A, Polymer chemistry》2004,42(4):999-1007
Free‐radical homo‐ and copolymerization behavior of N,N‐diethyl‐2‐methylene‐3‐butenamide (DEA) was investigated. When the monomer was heated in bulk at 60 °C for 25 h without initiator, rubbery, solid gel was formed by the thermal polymerization. No such reaction was observed when the polymerization was carried out in 2 mol/L of benzene solution with with 1 mol % of azobisisobutyronitrile (AIBN) as an initiator. The polymerization rate (Rp) equation was Rp ∝ [DEA]1.1[AIBN]0.51, and the overall activation energy of polymerization was calculated 84.1 kJ/mol. The microstructure of the resulting polymer was exclusively a 1,4‐structure where both 1,4‐E and 1,4‐Z structures were included. From the product analysis of the telomerization with tert‐butylmercaptan as a telogen, the modes of monomer addition were estimated to be both 1,4‐ and 4,1‐addition. The copolymerizations of this monomer with styrene and/or chloroprene as comonomers were also carried out in benzene solution at 60 °C. In the copolymerization with styrene, the monomer reactivity ratios obtained were r1 = 5.83 and r2 = 0.05, and the Q and e values were Q = 8.4 and e = 0.33, respectively. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 999–1007, 2004 相似文献
6.
Takayuki Nakai Yoshiko Murakami Yoshiaki Sasaki Isamu Fujiwara Shoji Tagashira 《Analytical sciences》2004,20(1):235-237
The extraction and separation of copper(II), zinc(II), cobalt(II), and cadmium(II) were investigated. Both copper(II) and zinc(II) formed ammine-complexes, while cadmium(II) and cobalt(II) formed hydroxide precipitates in an ammonia medium. By the addition of sodium dodecylsulfate (SDS), a copper(II) complex formed an ion-pair (copper-ammine-DS), which was extracted into the SDS phase. However, a zinc(II) complex did not form an ion-pair, and was soluble in water. Copper(II) ion was recovered by stripping (back-extraction) after the addition of hydrochloric acid. This method was applied to the separation of copper(II) in a brass alloy. 相似文献
7.
Takayuki Abe 《Mathematical Methods in the Applied Sciences》2004,27(9):1007-1048
This paper is concerned with the standard Lp estimate of solutions to the resolvent problem for the Stokes operator on an infinite layer with ‘Neumann–Dirichlet‐type’ boundary condition. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
8.
The potential of an N-Troc-protected sialic acid donor, equipped with phenylsulfenyl functionality as a leaving group, has been explored. As a result, the entitled donor was proven to be highly reactive and to have broad applicability toward the synthesis of variant sialo-glycans, which have N-glycolyl, de-N-acetyl, 1,5-lactam and 8-O-sulfo sialic acid analogs. 相似文献
9.
Jü rgen Herzog Takayuki Hibi Xinxian Zheng 《Transactions of the American Mathematical Society》2006,358(9):4119-4134
Squarefree monomial ideals arising from finite meet-semilattices and their free resolutions are studied. For the squarefree monomial ideals corresponding to poset ideals in a distributive lattice, the Alexander dual is computed.
10.
Takayuki Sakaguchi 《Optical Review》2003,10(3):136-139
We have succeeded in the operation of rotating a fine particle which was held without mechanical contact by circularly polarized laser beams with opposite propagation directions. A polystyrene latex particle 11.9 μm in diameter deformed in a disk-like shape was dispersed in water, and was trapped using the anti-parallel collinear laser beams which were set up so that they had the circular polarization rotating in the same direction. It was observed that the trapped particle rotated in the same direction as the rotation of the circular polarization of light. Inversion of the rotational direction of the circular polarization of light reversed the direction of the rotation of the particle. Although the rotational speed of a particle varied significantly from particle to particle, it was found to be proportional to the laser beam intensity. A typical value for the rotational speed per beam intensity was 2.1 Hz/W. 相似文献