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871.
Daisuke Nagai Akinori Suzuki Takaya Kuribayashi 《Macromolecular rapid communications》2011,32(4):404-410
Hydrogels were successfully synthesized utilizing CO2 as a gellant. A cross‐linking reaction of polyallylamine (PAA) with CO2 in the presence of 1,8‐Diazabicyclo[5,4,0]‐undec‐7‐ene (DBU) provided hydrogels bearing urea cross‐linking points and residual amino groups in the side chains. The obtained hydrogels absorbed CO2 at 25 °C and gave a maximum absorption four times larger than that of PAA aqueous solution and 2.8 times larger than that of the most commonly used absorbent, monoethanolamine. The PAA hydrogels desorbed the absorbed CO2 completely under a N2 atmosphere at 120 °C, and could be repeatedly recycled without loss of efficiency, indicating their potential application as recyclable CO2 absorption materials.
872.
Kunihiko Takabe Yasuhiro Iida Hidetaka Hiyoshi Masatoshi Ono Yoshihiko Hirose Yoshitaka Fukui Hidemi Yoda Nobuyuki Mase 《Tetrahedron: Asymmetry》2000,11(24):4825-4829
Enantioselective acetylation of 2-carbamoylmethyl-1,3-propanediol derivatives was catalyzed effectively by lipase PS to give monoacetates with high enantioselectivity: The enantioselectivity depended on the 2-carbamoylmethyl groups. The reaction of N-monoalkylcarbamoylmethyl-1,3-propanediol afforded the monoacetate with the (S)-configuration, whereas N,N-dialkylcarbamoylmethyl-1,3-propanediol gave the monoacetate with the (R)-configuration. 相似文献
873.
Guan-Yeow Yeap Wan-Sinn Yam Wen-Sheng Chang Ewa Gorecka Daisuke Takeuchi Kohtaro Osakada 《Phase Transitions》2013,86(3):256-268
A new series of 4′-substituted-7-(4″-decyloxybenzoyloxy)-4H-1-benzopyran-4-one esters have been synthesized and their mesomorphic properties have been studied along with the spectroscopic and optical-oriented technique in which the smectic layer spacing of compound with fluorine substituent has been well substantiated by X-ray diffraction. Phase transition temperatures and the respective enthalpy values of the title compounds are obtained from differential scanning calorimetry, whilst texture observation is performed under polarizing optical microscopy. The thermal data indicate that all title compounds are thermotropic exhibiting either monomorphism or variants of polymorphism. Crystal paramorphism is also observed for some of the title compounds. The variation in transition temperatures as a consequence of structural changes of the title compounds is discussed. 相似文献
874.
Guan-Yeow Yeap Elham A. Al-Taifi Chin-Hin Ong Wan Ahmad Kamil Mahmood Daisuke Takeuchi Masato M. Ito 《Phase Transitions》2013,86(6):483-496
A new series of non-symmetric liquid crystal dimers N-(4-(n-(4-(benzothiazol-2-yl)phenoxy)alkyloxy)benzylidene)-4-chloroaniline containing benzothiazole and benzylideneimine units connected by a flexible alkyl spacer, –(CH2) n –, with n ranging from 4 to 12 in even parity have been prepared. All five members of this homologous series exhibit an enantiotropic nematic phase. The compounds with greater n of 8–12 exhibit both nematic and smectic phases upon cooling. A notable feature among this series is that for the member with n?=?10, the smectic–nematic transition is also present. The nematic–isotropic transition temperatures and associated entropy changes with respect to all compounds in this series exhibit a dramatic dependence on the length of the flexible spacer. A comparison of the transitional properties of this series with those of α-(4-benzylidenechloroaniline-4′-oxy)-ω-[4-(thiophene-2-carboxyl)benzylideneaniline-4′-oxy]alkanes reveals that replacing benzothiazole moiety at one side of the flexible alkyl spacer reduces the nematic–isotropic transition temperature. 相似文献
875.
This article reports on a 1.3-μm edge emitting LED that has a high coupling efficiency to a single mode fiber and a high fiber output power. 1-4This E2LED was prepared using VIPS (V-grooved inner stripe on P-type substrate) technique with InP and InGaAsP layers suppressing the lasing action. 相似文献
876.
Atsushi Hosaka Tetsuo Hyodo Daisuke Jido Hideko Nagahiro Kanabu Nawa Shunsuke Ohkoda Sho Ozaki Yasuhiro Yamaguchi Shigehiro Yasui 《Few-Body Systems》2013,54(1-4):19-24
In hadron resonances different structures of hadronic composite (molecule) and elementary (quark-intrinsic) natures may coexist. We sketch discussions based on our previous publications on the origin of hadron resonances (Hyodo et al. Phys. Rev. C 78:025203, 2008) on exotic ${\bar D (B)}$ meson–nucleons as candidates of hadronic composites (Yamaguchi et al. Phys. Rev. D 84:014032, 2011) and on a 1 for the coexistence/mixing of the two different natures (Nagahiro et al. Phys. Rev. D 83:111504, 2011). 相似文献
877.
Yoshiki K. Tanaka Stefan Friedrich Hiroyuki Fujioka Hans Geissel Ryugo S. Hayano Satoru Hirenzaki Kenta Itahashi Satoshi Itoh Daisuke Jido Volker Metag Hideko Nagahiro Mariana Nanova Takahiro Nishi Kota Okochi Haruhiko Outa Ken Suzuki Takatoshi Suzuki Helmut Weick 《Few-Body Systems》2013,54(7-10):1263-1266
We are going to perform an inclusive spectroscopy experiment of η′ mesic nuclei with the 12C(p,d) reaction to study in-medium properties of the η′ meson. In nuclear medium, the η′ meson mass may be reduced due to partial restoration of chiral symmetry. In case of sufficiently large mass reduction and small absorption width of η′ at normal nuclear density, peak structures of η′ mesic states in 11C will be observed near the η′ emission threshold even in an inclusive spectrum. The experiment will be carried out at GSI with proton beam supplied by SIS using FRS as a spectrometer. The detail of the experiment is described. 相似文献
878.
Electron paramagnetic resonance (EPR) spin-probe method was used to investigate structural aspects of psoriasis vulgaris SC (pv-SC). EPR spectra of the SC samples were analyzed using order parameter (S 0) and rotational diffusion rates. A little, broad three-line pattern of 5-doxylstearic acid (spin probe) in pv-SC was observed. The spectral pattern of pv-SC is quite different from those of control SC reported. The S 0 values obtained for the pv-SC and the control were approximately 0.20 and 0.49, respectively. The statistical analysis suggests that the 0.20 value of pv-SC is significantly smaller than the 0.49 value of the control (p < 0.01). The rotational diffusion rates for the probe motion in the SC were faster than those of the control. Moreover, there was no spectral difference of the glass plate with the SC against the static magnetic field, except for the signal intensity. Therefore, the pv-SC is less rigid of the structure than that of the control SC, indicating irregular architecture of pv-SC. The present results suggest that the EPR assay is of great use for evaluating various SC function and can be extended to other skin diseases with abnormal keratinization. 相似文献
879.
Sakamoto M Tanaka D Tsunoyama H Tsukuda T Minagawa Y Majima Y Teranishi T 《Journal of the American Chemical Society》2012,134(2):816-819
The structures of nanomaterials determine their individual properties and the suprastructures they can form. Introducing anisotropic shapes and/or interaction sites to isotropic nanoparticles has been proposed to extend the functionality and possible suprastructure motifs. Because of symmetric anisotropy, Platonic solids with regular polygon faces are one of the most promising nanoscale structures. Introduction of Platonic solid anisotropy to isotropic nanomaterials would expand the functionality and range of possible suprastructure motifs. Here, we demonstrate a novel strategy to obtain nano-Platonic solids through the face coordination of square porphyrins on an inscribed Au sphere with adequate size. The face coordination of the multidentate porphyrin derivatives, with four acetylthio groups facing the same direction, on the Au cluster encased the Au cluster in a Platonic hexahedron with six porphyrin faces. Transmission electron microscopy, mass spectrometry, elemental analysis, and scanning tunnelling microscopy were used to confirm the formation of the nano-Platonic hexahedron. 相似文献
880.
Yoshiki Ohgo Masashi Takahashi Kazuyuki Takahashi Yukiko Namatame Hisashi Konaka Hatsumi Mori Saburo Neya Shinya Hayami Daisuke Hashizume Mikio Nakamura 《Hyperfine Interactions》2012,206(1-3):23-33
This review describes the switching behaviors of the electronic structure, which were observed in iron(III) porphyrinoids, by the addition of external stimuli. The combined analysis by various methods, such as EPR, M?ssbauer, SQUID, single crystal X-ray structure analysis, revealed a wide variety of electronic structures of the heme related complexes. This paper focuses in particular on the spin-crossover phenomenon in the solid state. An overview of spin-crossover phenomena found in iron(III) porphyrinoids between (i) S?= 5/2 and S?= 1/2, (ii) S?= 3/2 and S?= 1/2, (iii) S?= 5/2 and S?= 3/2, will be described. 相似文献