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131.
R. B. Morgunov A. I. Dmitriev A. S. Chernen’kaya K. Yakushi K. Yamamoto Y. Tanimoto 《Journal of Experimental and Theoretical Physics》2010,111(5):857-864
Sharp changes in the integral intensity and linewidth of the ESR spectrum that accompany the localization of the charge carriers
have been revealed in α’-(BEDT-TTF)2IBr2 crystals. It has been found that the types of localization in two compounds under investigation are different: charge carriers
in β″-(BEDT-TTF)4NH4[Cr(C2O4)3] are localized on irregular defects of the crystal lattice, whereas charge carriers in α’-(BEDT-TTF)2IBr2 are localized at the regular positions of the unit cell. The exchange narrowing of the ESR line and a sharp decrease in the
dc and ac magnetic susceptibilities are observed in α’-(BEDT-TTF)2IBr2 at low temperatures T < 50 K. The dc and ac magnetic susceptibilities observed in α’-(BEDT-TTF)2IBr2 at high temperatures T > 50 K differ from each other, because the thermally activated hopping frequency of the charge carriers is higher than the
frequency of the measuring UHF field of an ESR spectrometer. 相似文献
132.
Hifumi H Yamaoka S Tanimoto A Citterio D Suzuki K 《Journal of the American Chemical Society》2006,128(47):15090-15091
A new nanoparticulate inorganic-organic hybrid-type positive contrast agent (CA), PGP/dextran-K01, was synthesized based on a GdPO4 inorganic core as a relaxation-time-shortening moiety and a dextran-coating, which generates monodispersibility in water, a high relaxation-time-shortening effect by retaining a large number of water molecules in proximity of the core and toxicity reduction in in-vivo studies. This PGP/dextran-K01 nanoparticle has high r1 and r2 values and a significantly low r2/r1 value, 1.1, which is unprecedented and which is the lowest value among existing nanoparticulate CAs indicating that PGP/dextran-K01 is a positive contrast agent. Because of this low r2/r1 value and the nanoparticulate shape, PGP/dextran-K01 will be a useful clinical substitute for negative CAs based on iron oxides. 相似文献
133.
Yoh Tanimoto 《Communications in Mathematical Physics》2012,314(2):419-441
In higher dimensional quantum field theory, irreducible representations of the Poincaré group are associated with particles. Their counterpart in two-dimensional massless models are ??waves?? introduced by Buchholz. In this paper we show that waves do not interact in two-dimensional M?bius covariant theories and in- and out-asymptotic fields coincide. We identify the set of the collision states of waves with the subspace generated by the chiral components of the M?bius covariant net from the vacuum. It is also shown that Bisognano-Wichmann property, dilation covariance and asymptotic completeness (with respect to waves) imply M?bius symmetry. Under natural assumptions, we observe that the maps which give asymptotic fields in Poincaré covariant theory are conditional expectations between appropriate algebras. We show that a two-dimensional massless theory is asymptotically complete and noninteracting if and only if it is a chiral M?bius covariant theory. 相似文献
134.
Higaki A Tamada T Sone T Kanki A Sato T Tanimoto D Higashi H Ito K 《Magnetic resonance imaging》2012,30(5):689-693
Objective
The objective was to clarify the clinical factors that might affect the degree of hepatic parenchymal enhancement at gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance (MR) imaging.Materials and Methods
A total of 84 patients with (n=63) and without chronic liver disease (n=21) underwent Gd-EOB-DTPA-enhanced MR imaging. Contrast-enhanced MR images of hepatobiliary phase (HP) were obtained at 20 min after Gd-EOB-DTPA administration. The relative enhancement (RE) of liver parenchyma at 20 min HP was calculated from region of interest measurements at each patient. Then, these results were correlated with various clinical parameters using Pearson correlation coefficient or Spearman rank correlation coefficient. Furthermore, the predictor of the degree of hepatic parenchymal enhancement was determined using multiple regression analysis.Results
The presence or absence of chronic liver disease (P=.002), ascites (P=.005) and splenomegaly (P=.027), and the values of prothrombin activity (P=.008), total bilirubin (T-Bil) (P=.001), albumin (P=.001), aspartate aminotransferase (AST) (P=.002) and cholinesterase (P=.007) were significantly correlated with the RE of liver parenchyma at 20 min HP. Among these parameters, increases of T-Bil (P=.011 to .028) and AST (P=.018 to .049) were predictors of decreased hepatic parenchymal enhancement.Conclusions
Hepatic parenchymal enhancement of Gd-EOB-DTPA was affected by various clinical parameters. Impaired hepatobiliary enhancement may be predicted by routine biochemical tests, such as T-Bil and AST. 相似文献135.
Gas-phase E.P.R. spectra of 35ClO have been measured accurately both in the J=5/2 and J=3/2 rotational levels, using C-band (4·4 GHz) and X-band (9·4 GHz) microwaves, respectively. Special attention has been paid to separate the spectral lines of 35ClO from those of 37ClO. Analysis of the spectra has resulted in the simultaneous determination of the hyperfine parameters h and b and, when combined with a-(b+c)/2 obtained by microwave spectroscopy, the hyperfine parameters a, b and c are all determined. Molecular constants which describe the distribution of the unpaired electron around the chlorine nucleus are derived from them. The molecular g values of the rotational levels indicate the mixing of the 2Π state both with the 2Σ+ and with the 2Δ electronic excited states. 相似文献
136.
137.
The top quark mass and the flavour mixing are studied in the context of a seesaw model of quark masses based on the gauge group SU(2)L × SU(2)R × U(1). Six isosinglet quarks are introduced to give rise to the mass hierarchy of ordinary quarks. In this scheme, we reexamine a mechanism for the generation of the top quark mass. It is shown that, in order to prevent the seesaw mechanism to act for the top quark, the mass parameter of its isosinglet partner must be much smaller than the breaking scale of SU(2)R. As a result the fourth lightest up quark must have a mass of the order of the breaking scale of SU(2)R, and a large mixing between the right-handed top quark and its singlet partner occurs. We also show that this mechanism is compatible with the mass spectrum of light quarks and their flavour mixing. 相似文献
138.
R. B. Morgunov V. L. Berdinskii M. V. Kirman Y. Tanimoto S. V. Chapyshev 《High Energy Chemistry》2007,41(1):33-36
The magnetic properties and the buildup kinetics of the photolysis products of crystalline 2,4,6-triazido-3,5-dichloropyridine at temperatures of 2–300 K were studied with the use of a superconducting quantum interference device (SQUID). Under UV irradiation, the azide groups of the triazide decompose to afford high-spin nitrenes. The diamagnetic sample is converted into a paramagnetic with an average spin of 1.8 after 30 min of irradiation. The rate of triazide photolysis increases with a decrease in temperature down to 2 K. 相似文献
139.
Hiroki Hifumi Akihiro Tanimoto Aki Honda Daniel Citterio Koji Suzuki 《Analytical sciences》2007,23(10):1159-1165
Magnetic resonance angiography (MRA) is an imaging method to examine blood vessels based on the magnetic resonance imaging (MRI) technique. For this purpose, blood pool contrast agents have been developed to selectively increase the signal intensity of the intravascular lumen for improvement of the contrast-to-noise ratio in MR images. Here, we describe the design and the syntheses of six novel sulfonated contrast agents (KMR-Sulfo1 - 6), their chemical properties and their in vivo applications. In this study, we investigated the lipophilicity and the hydrophilicity of a gadolinium complex using a convenient two-step synthesis route, with the goal of prolonging the plasma half-life by binding mainly to human serum albumin. We confirmed that KMR-Sulfo5 fulfilled the requirements as a blood pool contrast agent: it showed a sufficient relaxivity r(1) of 5.9 mM(-1) s(-1), a long plasma half-life of 25.7 min and complete elimination from the body within 12 h after the administration. 相似文献
140.
Ossipyan Yu. A. Morgunov R. B. Baskakov A. A. Orlov A. M. Skvortsov A. A. Inkina E. N. Tanimoto Y. 《JETP Letters》2004,79(3):126-130
JETP Letters - A microwave magnetic field crossed with a static field was found to exert a resonance effect on the dislocation mobility in single crystals of p-type silicon. The frequency of... 相似文献