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61.
Behnia K Bel R Kasahara Y Nakajima Y Jin H Aubin H Izawa K Matsuda Y Flouquet J Haga Y Onuki Y Lejay P 《Physical review letters》2005,94(15):156405
We present a study of thermal conductivity in the normal state of the heavy-fermion superconductor URu2Si2. Ordering at 18 K leads to a steep increase in thermal conductivity and (in contrast with all other cases of magnetic ordering in heavy-fermion compounds) to an enhancement of the Lorenz number. By linking this observation to several other previously reported features, we conclude that most of the carriers disappear in the ordered state and this leads to a drastic increase in both the phononic and electronic mean free path. 相似文献
62.
Izawa K Behnia K Matsuda Y Shishido H Settai R Onuki Y Flouquet J 《Physical review letters》2007,99(14):147005
We present a study of thermoelectric coefficients in CeCoIn5 down to 0.1 K and up to 16 T in order to probe the thermoelectric signatures of quantum criticality. In the vicinity of the field-induced quantum critical point, the Nernst coefficient nu exhibits a dramatic enhancement without saturation down to the lowest measured temperature. The dimensionless ratio of the Seebeck coefficient to the electronic specific heat shows a minimum at a temperature close to threshold of the quasiparticle formation. Close to Tc(H), in the vortex-liquid state, the Nernst coefficient behaves anomalously in puzzling contrast with other superconductors and standard vortex dynamics. 相似文献
63.
Model calculations on anion carrier ligands related to trifluoroacetophenone were carried out using the semiempirical AM 1 method in order to investigate the factors involved in such anion-ligand complexation. The reaction of halogen derivatives of acetophenone with various nucleophiles such as water, carbonic acid, and bicarbonate anion was studied. By this means, the effect of various structural changes, such as variation of the ring substituents and variation of the degree and type of halogen atom substitution, could be determined. It is shown that in terms of relative stability, fluorine derivatives are preferable to chlorine derivatives for the binding of water and carbonic acid. Monosubstitution of a methoxy group in the ortho position of the trifluoroacetophenone ring also brought about stability in the case of the hydration reaction. An electron-withdrawing ester group in the para position on the trifluoroacetophenone ring brings about stabilization also. 相似文献
64.
Spencer introduced a chip firing game on a line, which was generalized by Björner, Lovasz and Shor to graphs. This paper characterizes those configurations which may be repeated in a game, and analyzes the game forn-cycles.This research was funded by NSERC operating grants. 相似文献
65.
The syntheses of azabicyclo[3.1.0]hexane transition state (TS) analogs are described. Cyclopropanation of N-Boc-3-pyrroline with ethyl diazoacetate afforded a 1.6:1 exo/endo ratio of the resulting ester. Reduction of the endo-isomer with LiAlH4 yielded the alcohol which was phosphorylated, or iodinated to provide access to aglycon containing TS analogs. 相似文献
66.
Allylic alcohols have been found to react with Fe2(CO)9 in ether to afford after addition of HBF4/acetic anhydride, the corresponding (η3-allyl)Fe(CO)4+BF4?- species (I) in moderate to good yields. The geometry of the starting alcohol is retained in the product complex; thus E-crotyl and -cinnamyl alcohols led to anti-substituted complexes, whereas the corresponding Z-alcohols produced syn-complexes. 相似文献
67.
Lemos Paulo Vitor França Barbosa Leandro Santos Ramos Ingrid Graça Coelho Rodrigo Estevam Druzian Janice Izabel 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2555-2567
Journal of Thermal Analysis and Calorimetry - The thermal features of potato, banana, corn and cassava starches were correlated with structural properties. These starches were characterized by SEM,... 相似文献
68.
69.
Kenji Sakamaki Hiroaki Wada Hiroshi Nozaki Yoshichika Onuki Maki Kawai 《Molecular Crystals and Liquid Crystals》2013,570(2):99-104
Abstract Evidence for bulk superconductivity in Nb2SC0.90 carbosulfide is presented. Diamagnetic volume fraction of Nb2SC0.90 was precisely determined with low applied magnetic fields which were corrected by 6N lead rod as an internal standard. Based on magnetic field dependence of magnetic moment at several constant temperature's below TC = 5 K, Nb2SC0.90 is found to be a type II superconductor with relatively high H C2 and low HC1. 相似文献
70.
Onuki A 《The Journal of chemical physics》2008,128(22):224704
We calculate the ion distributions around an interface in fluid mixtures of highly polar and less polar fluids (water and oil) for two and three ion species. We take into account the solvation and image interactions between ions and solvent. We show that hydrophilic and hydrophobic ions tend to undergo a microphase separation at an interface, giving rise to an enlarged electric double layer. We also derive a general expression for the surface tension of electrolyte systems, which contains a negative electrostatic contribution proportional to the square root of the bulk salt density. The amplitude of this square-root term is small for hydrophilic ion pairs but is much increased for hydrophilic and hydrophobic ion pairs. For three ion species, including hydrophilic and hydrophobic ions, we calculate the ion distributions to explain those obtained by x-ray reflectivity measurements. 相似文献