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111.
T. Nishi T. Takahashi H.J. Im K. Miyagawa A. Kawamoto 《Solid State Communications》2005,134(3):189-193
The direct observation of the phase separation between the metallic and insulating states of 75%-deuterated κ-(ET)2Cu[N(CN)2]Br (d33) using infrared magneto-optical imaging spectroscopy is reported, as well as the associated temperature, cooling rate, and magnetic field dependencies of the separation. The distribution of the center of spectral weight (〈ω〉) of d33 did not change under any of the conditions in which data were taken and was wider than that of the non-deuterated material. This result indicates that the inhomogenity of the sample itself is important as part of the origin of the metal-insulator phase separation. 相似文献
112.
Bungo Ochiai Tokinori Iwamoto Toyoharu Miyagawa Daisuke Nagai Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(19):4941-4947
We established a self‐catalyst system for solid phase incorporation of gaseous carbon dioxide into terpolymers prepared by polymerization of glycidyl methacrylate, N‐benzyl‐N‐[2‐(methacryrolroxy)ethyl]‐N,N‐dimethylammonium bromide, and methyl methacrylate. Terpolymer composition affected the incorporation behavior where the terpolymer with higher oxirane content exhibited higher efficiency of carbon dioxide incorporation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4941–4947, 2004 相似文献
113.
Masashi Miyagawa 《Annals of Operations Research》2009,172(1):349-361
This paper develops a simple analytical model for determining the hierarchical system of road networks. The model is based
on a grid road network where roads are classified into three types according to road widths and travel speeds. We derive the
optimal ratios of road areas that minimize the average and maximum travel time. Minimizing the average travel time provides
an efficient solution, whereas minimizing the maximum travel time provides an equitable solution. Both of the solutions are
expressed in terms of road widths and travel speeds. As an application of the grid network model, we evaluate the hierarchical
system of the road network of Tokyo. 相似文献
114.
[reaction: see text] The ring flip of a carbohydrate is employed for the tongs-like movable component of a metal ion sensor. A pair of separated pyrene groups attached to the carbohydrate component are placed side by side when it recognizes metal ions, affording excimer fluorescence. This novel molecular sensor is selective for Zn(2+) and Cd(2+). 相似文献
115.
Yamamoto Y Miura T Suzuki M Kawamura N Miyagawa H Nakamura T Kobayashi K Teranishi T Hori H 《Physical review letters》2004,93(11):116801
We report the first direct observation of ferromagnetic spin polarization of Au nanoparticles with a mean diameter of 1.9 nm using x-ray magnetic circular dichroism (XMCD). Owing to the element selectivity of XMCD, only the gold magnetization is explored. Magnetization of gold atoms as estimated by XMCD shows a good agreement with results obtained by conventional magnetometry. This evidences intrinsic spin polarization in nanosized gold. 相似文献
116.
M. Nakano H. Watanabe T. Shimizu N. Miyagawa S. Morita H. Katagiri H. Ishiguro 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(2):319-322
The fire and explosion of the Bituminization Demonstration Facility at PNC Tokai Works were occurred on March 11th, 1997. As soon as the fire occurred, environmental monitoring was started. The influence of accidental release was recognized from some samples of airborne dust and surface soil on site. No influence was recognized from the samples off site except the airborne dust collected at O-arai (20 km south). The official statement by the Nuclear Safety Commission of Japan was: "It was less than the value which has an influence on the environment and health." 相似文献
117.
1H NMR and static susceptibility measurements have been performed in an organic Mott insulator with a nearly isotropic triangular lattice, kappa-(BEDT-TTF)2Cu2(CN)(3), which is a model system of frustrated quantum spins. The static susceptibility is described by the spin S=1/2 antiferromagnetic triangular-lattice Heisenberg model with the exchange constant J approximately 250 K. Regardless of the large magnetic interactions, the 1H NMR spectra show no indication of long-range magnetic ordering down to 32 mK, which is 4 orders of magnitude smaller than J. These results suggest that a quantum spin liquid state is realized in the close proximity of the superconducting state appearing under pressure. 相似文献
118.
119.
Mechanical property and molecular weight distribution changes with photo- and chemical-degradation on LDPE films 总被引:1,自引:0,他引:1
Eiichi Miyagawa Katsuhisa Tokumitsu Akira Tanaka 《Polymer Degradation and Stability》2007,92(10):1948-1956
In order to clarify the effect of photo- and chemical-degradation on the structure of polyethylene materials, the change in molecular weight distribution and mechanical properties of photo- and chemical-degraded LDPE films were investigated. The molecular weight distribution was significantly changed with photo-exposing times, and the drastic change appeared especially for 8 days-exposed samples where the molecular weight of the high molecular weight fraction increased. However, the molecular weight of the lower molecular weight fraction was almost the same for all the photo-exposed films, irrespective of irradiation time, and also for chemical-degraded films. It is suggested that the molecular chains with a certain length, which consist of a crystal lamellae in spherulites, cannot be broken by photo-irradiation. Consequently, there would be threshold for the molecular weight in terms of photo-degradation process, and almost the same threshold can be observed for the chemical-etching films. Stress-strain curves were measured for photo-degraded films and their “quenched films after remolding” and “annealed films after remolding”, and chemical-degraded films. 相似文献
120.
Atsushi Miyagawa Shunya Takeuchi Shinji Itoda Sanami Toyama Kenta Kurimoto Hatsuo Yamamura 《合成通讯》2016,46(22):1790-1795
2-Deoxy sugars are attractive compounds in synthetic chemistry with regard to reactivity and stereoselectivity. Moreover, their ability to inhibit enzymes and metabolism is significant in biology. In this study, uridine-5′-diphosphate (UDP)-2-deoxy glucose (11) and galactose (12) were synthesized chemically. These sugar donors for glycosyltransferases were obtained α-selectively via phosphorylation using thioglycosides, coupling reaction with uridine-5′-monophosphate (UMP)-morpholidate, and moderate deacetylation. Isolation was carried out by sequential silica-gel chromatography using two kinds of developing solvents in a refrigerator. The structures were elucidated from the NMR results. Investigation of stability showed that the synthesized UDP-2-deoxy sugars were hydrolyzed much faster in buffer (pH 4) than the natural UDP sugars. 相似文献