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71.
Atsuhiro Fujimori Hiroko Hoshizawa Satoshi Kobayashi Kaname Kanai Yukio Ouchi Kazuhiko Seki 《Journal of Polymer Science.Polymer Physics》2008,46(5):534-546
Comb copolymers containing both hydrogenated and fluorinated side‐chains were prepared by copolymerization using acrylic or methacrylic monomers in several ratios. The crystal structures of these copolymers and layer structures of their organized molecular films were investigated by wide‐angle X‐ray diffraction (WAXD), small‐angle X‐ray scattering (SAXS), and out‐of plane X‐ray diffraction. Further, to selectively estimate the regularity of shorter fluorocarbon side‐chains, organized molecular films of copolymers were investigated by polarized near‐edge X‐ray adsorption fine structure (NEXAFS) spectroscopy. From the results of these measurements, it was inferred that these copolymers formed highly ordered layer structures, and a long spacing was predominantly determined by the arrangement of hydrogenated side‐chains, except in copolymers having extremely high fluorocarbon contents. In the case of the organized molecular films, the fluorinated side‐chains of methacrylate copolymers cannot form a highly ordered arrangement, whereas those of acrylate copolymers were oriented on monolayers. However, in both cases, the hydrogenated side‐chains predominantly formed layer structures in the organized films, and the fluorinated side‐chains did not contribute to the formation of the layer structures. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 534–546, 2008 相似文献
72.
In a prototype of an adenine analyser, adenosine and adenine nucleotides were derivatized with a fluorescent reagent, bromoacetaldehyde, after separation on a Hitachi gel No. 3012-N column by high-performance liquid chromatography. The previous analyser was improved by using a shorter reaction coil and by introduction of a Hitachi gel No. 3013-N with 5-microns particles of porous polystyrene-divinylbenzene, and applied to estimate the freshness of porgy. Total amounts of ATP, ADP and AMP in an isolated muscle just after death gradually decreased to 60% of the original amount after 5 h, and the ATP content rapidly decreased to 20% after 1 h. A good correlation was found between the levels of total adenine compounds and the energy charge values obtained from nineteen porgies frozen at a prerigour state. On the other hand, there existed no relationship between total adenine levels and the K values, which were indices for estimating freshness of fish. The analyser will be useful to evaluate the freshness of tissues and cells based on the higher contents of total adenine compounds, especially ATP. 相似文献
73.
Atsuya Muranaka Masaki Yokoyama Yotaro Matsumoto Masanobu Uchiyama Akihiko Tsuda Atsuhiro Osuka Nagao Kobayashi 《Chemphyschem》2005,6(1):171-179
The magnetic circular dichroism (MCD) spectra of doubly and triply linked fused bisporphyrins (2MD and 2MT, M = Ni, Zn, Cu, Pd, and H2) and triply linked higher oligomers (3ZnT and 4ZnT) have been measured, and their Q-bands assigned based on the results of INDO/s calculations. In contrast to the Faraday A term observed for the Q(0,0) band of Ni(II) tetraphenylporphyrin, a single positive Faraday B term was observed for the lowest energy transition of the fused systems. The calculations indicated that the molecular orbitals (MOs) of the directly fused porphyrins consist of linear combinations of the constituent monomeric MOs, and that the effect of lowering the symmetry is always larger on the lowest unoccupied molecular orbital (LUMO) than on the highest occupied molecular orbital (HOMO). On the basis of Michl's perimeter model, these features can be correlated with the observed positive MCD signs in the near infrared region. A weak absorption band at 600-700 nm for the fused dimers can be assigned to a short-axis polarized Q transition. 相似文献
74.
A triangulation of a closed surface is said to be d-covered if all of its edges are covered by vertices of degree d. We shall give constructive characterizations of 5- and 6-covered triangulations.
Received: July 17, 1998?Final version received: January 12, 2000 相似文献
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77.
Zhidkov I. S. Belik A. A. Kukharenko A. I. Cholakh S. O. Taran L. S. Fujimori A. Streltsov S. V. Kurmaev E. Z. 《JETP Letters》2021,114(9):556-560
JETP Letters - The results of full study of X-ray photoelectron spectra (XPS) of spin-liquid candidate CuAl2O4 including the measurements of high-energy resolved core level (Cu $$2p$$ , Al $$3p$$ ,... 相似文献
78.
Chihiro Maeda Pyosang Kim Sung Cho Jong Kang Park Jong Min Lim Dongho Kim Prof. Dr. Josh Vura‐Weis Michael R. Wasielewski Prof. Dr. Hiroshi Shinokubo Prof. Dr. Atsuhiro Osuka Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(17):5052-5061
meso‐Triazolyl‐appended ZnII–porphyrins were readily prepared by CuI‐catalyzed 1,3‐dipolar cycloaddition of benzyl azide to meso‐ethynylated ZnII–porphyrin (click chemistry). In noncoordinating CHCl3 solvent, spontaneous assembly occurred to form tetrameric array ( 3 )2 from meso–meso‐linked diporphyrins 3 , and dodecameric porphyrin squares ( 4 )4 and ( 5 )4 from the L ‐shaped meso–meso‐linked triporphyrins 4 and 5 . The structures of these assemblies were examined by 1H NMR spectra, absorption spectra, and their gel permeation chromatography (GPC) retention time. Furthermore, the structures of the dodecameric porphyrin squares ( 4 )4 and ( 5 )4 were probed by small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) measurements in solution using a synchrotron source. Excitation‐energy migration processes in these assemblies were also investigated in detail by using both steady‐state and time‐resolved spectroscopic methods, which revealed efficient excited‐energy transfer (EET) between the meso–meso‐linked ZnII–porphyrin units that occurred with time constants of 1.5 ps?1 for ( 3 )2 and 8.8 ps?1 for ( 5 )4. 相似文献
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80.
Yoshida T Nishi I Ideta S Fujimori A Kubota M Ono K Kasahara S Shibauchi T Terashima T Matsuda Y Ikeda H Arita R 《Physical review letters》2011,106(11):117001
We have studied the three-dimensional shapes of the Fermi surfaces (FSs) of BaFe(2)(As(1-x)P(x))(2) (x=0.38), where superconductivity is induced by isovalent P substitution and by angle-resolved photoemission spectroscopy. Moderately strong electron mass enhancement has been identified for both the electron and hole FSs. Among two observed hole FSs, the nearly two-dimensional one shows good nesting with the outer two-dimensional electron FS, but its orbital character is different from the outer electron FS. The three-dimensional hole FS shows poor nesting with the electron FSs. The present results suggest that the three dimensionality and the difference in the orbital character weaken FS nesting while partial nesting among the outer electron FSs of d(xy) character and/or that within the three-dimensional hole FS becomes dominant, which may lead to the nodal superconductivity. 相似文献