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61.
Naofumi Tsukada Makiko Wada Naoki Takahashi Yoshio Inoue 《Journal of organometallic chemistry》2009,694(9-10):1333-1338
Novel dinuclear palladium complexes having two isocyanide ligands were synthesized by using a binucleating ligand, N,N′-bis[2-(diphenylphsphino)phenyl]formamidinate (dpfam). The structure of [Pd2(μ-dpfam)(tert-BuNC)2]Cl was confirmed by X-ray analysis, showing that the Pd–Pd bond length of 2.5824(3) Å falls well within the range of those for known dipalladium complexes having the edge-sharing structure and two isocyanides coordinate to palladium in almost parallel and in close proximity. The dinuclear complex [Pd2(μ-dpfam)(tert-BuNC)2]PF6 served as catalyst for pyrrole formation from tert-butylisocyanide and various alkynes. 相似文献
62.
An exact analytical formula of the frequency shift and dissipated power in noncontact atomic force microscopy (nc-AFM) is obtained, in the case of a tip-surface interaction force with an inverse power law. The frequency shift for various tip shapes is evaluated. It is confirmed that the tip-height dependence of the analytical frequency shift shows very good agreement with that of the experimental one. The tip-height dependence of the dissipated power derived from a Langevin equation approach is also evaluated. 相似文献
63.
The complex two-plane Grassmannian carries a K?hler structure J and also a quaternionic K?hler structure ?. For we consider the classes of connected real hypersurfaces (M, g) with normal bundle such that and are invariant under the action of the shape operator. We prove that the corresponding unit Hopf vector fields on these hypersurfaces
always define minimal immersions of (M, g), and harmonic maps from (M, g), into the unit tangent sphere bundle with Sasaki metric . The radial unit vector fields corresponding to the tubular hypersurfaces are also minimal and harmonic. Similar results
hold for the dual space .
(Received 27 August 1999; in revised form 18 November 1999) 相似文献
64.
65.
Yasuhiro Tsukada Hiroyuki Furutani Yoshikazu Abe Keishi Monda Motoi Kawatsura 《Tetrahedron letters》2006,47(11):1801-1804
Various types of differently fluorinated-alkyl sulfate ionic liquids have been prepared; the hydrophobicity was dependent on the content ratio of the fluorine on the alkyl sulfate anion and 2,2,3,3,4,4,5,5-octafluoropentyl sulfate salts showed hydrophobic properties. Melting point and viscosity were also dependent on the fluorine contents of the anionic part, while conductivity was determined by the cationic part and not influenced by the fluorine contents. Efficient lipase-catalyzed transesterification was demonstrated using hydrophobic 1-butyl-3-methylimidazolim 2,2,3,3,4,4,5,5-octafluoropentyl sulfate ([bmim][C5F8]) as solvent. 相似文献
66.
Measurement of evaporation residue cross-sections of the reaction 30Si + 238U at subbarrier energies
K. Nishio S. Hofmann F. P. Heßberger D. Ackermann S. Antalic V. F. Comas Z. Gan S. Heinz J. A. Heredia H. Ikezoe J. Khuyagbaatar B. Kindler I. Kojouharov P. Kuusiniemi B. Lommel R. Mann M. Mazzocco S. Mitsuoka Y. Nagame T. Ohtsuki A. G. Popeko S. Saro H. J. Schött B. Sulignano A. Svirikhin K. Tsukada K. Tsuruta A. V. Yeremin 《The European Physical Journal A - Hadrons and Nuclei》2006,29(3):281-287
The reaction 30Si + 238U → 268Sg* was studied at beam energies close to the Coulomb barrier. At a center-of-mass energy of E
c.m. = 144.0MeV for reactions at half thickness of the target we measured three decay chains of 263Sg produced by evaporation of five neutrons. The cross-section was ( 67+67
-37) pb. At E
c.m. = 133.0MeV we measured three spontaneously fissioning nuclei which we assigned to the isotope 264Sg. The production cross-section was ( 10+10
-6) pb and a half-life of ( 120+126
-44) ms was determined. This half-life is a factor of twenty shorter than theoretical predictions. At E
c.m. = 128.0MeV an upper cross-section limit of 15pb was measured. The cross-section data reveal a strong influence of the orientation
of the deformed target nucleus on the production yield. Compared to excitation functions measured for the lighter system 16O + 238U → 254Fm*, a reduction of the fusion probability was observed at low beam energies indicating increasing competition from quasifission
processes. 相似文献
67.
From several large supercell MD simulations with an empirical tight-binding method, we have found the long-range structure on the dihydride Si(001) surface. This structure can be viewed as the well-known canted phase with domain walls. The formation energy of a single domain wall on the surface is estimated to be 1.3–1.5 eV. 相似文献
68.
69.
H. Nakahara M. Tsukada A. Moriizumi K. Horiuchi Y. Murakami 《Journal of Radioanalytical and Nuclear Chemistry》1982,72(1-2):377-391
The improvement obtained by epithermal neutron activation analysis was studied in terms of the detection sensitivity and precision
in the γ-ray spectrometry for geological and biological reference samples. For geological samples, small improvement was observed
only for the elements As, Ba, Sb, Se and U. For biological samples, however, large improvement was observed for As, Br, Sb
and U. The ratio of the resonance integral to the effective thermal-neutron capture cross section was observed for 19 nuclides.
The effect of the (n, p) reaction to the determination of Al and Mg by the ordinary reaktor-neutron activation analysis was
estimated. 相似文献
70.
The coherent quantum transport properties through the spin-polarized polyphenoxyl radical molecule have been investigated, using the density-functional-derived tight-binding model and the Green's functions method. The majority and minority spin components exhibit considerably different transmission spectra in the vicinity of the Fermi level. Namely, each spin component carries a different amount of current when the bias voltage is applied between the two electrodes that sandwich the polyradical molecule. Therefore, if the magnetization axis of the polyradical is fixed by the external magnetic field, and if the spin flip does not occur during the transmission, the assumed molecular bridge is expected to work as a spin filter or a spin valve. Furthermore, as long as the bias voltage is weak, the total spin current is observed to be larger than the current through its reduced molecular form. It indicates that the adsorption of some chemical species on the radical sites can be sensed by the change in conductance of the molecular bridge. 相似文献