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111.
We have discussed the quark-lepton mass matrices with the U(1) and O(3) flavor symmetry in SU(5), which lead to the large mixing angle MSW solution of solar neutrinos.  相似文献   
112.
113.
ABSTRACT

Four positional isomers of 61,6n-di-O-(D-galactopyranosyl)cyclomaltooctaoses (cG8s, γ-cyclodextrins) (n = 2?5) were chemically synthesized using the trichloroacetimidate method. The desired compounds having two α-(1→6)-linkages were isolated from a mixture of configurational isomers by HPLC, and their structures were confirmed by 13C NMR spectroscopy and FAB-high resolution mass spectra (HRMS). The elution behavior of their four positional isomers on an ODS column by HPLC is discussed.  相似文献   
114.
The contributions of several different subsystems to the magnetic properties of Ge0.99Mn0.01 nanowires are distinguished. The ferromagnetic resonance spectrum is found to have four components, two of which have the same temperature dependence and a Lorentzian shape. Presumably, these components correspond to the excitation of spin waves in the Mn3+ ion subsystem under the simultaneous influence of exchange and dipole-dipole interactions. There is also another Lorentzian-shaped component corresponding to resonance in the subsystem of localized Mn2+ centers. The fourth spectrum component has an asymmetric Dyson shape and is related to the resonance of mobile paramagnetic centers. A correlation is found between the temperature dependences of the spectral parameters of the magnetic resonances of the localized centers (Mn3+ and Mn2+ ions) and the charge carrier subsystem. This correlation indicates that the ferromagnetic exchange between the localized centers is due to carrier spin transport.  相似文献   
115.
116.
We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) and is consistent with the overall Super-K measurement.  相似文献   
117.
Two recent deformation schemes for quantum field theories on two-dimensional Minkowski space, making use of deformed field operators and Longo–Witten endomorphisms, respectively, are shown to be equivalent.  相似文献   
118.
The protecting-group-free asymmetric total synthesis of (?)-rosmarinecine was achieved in only four steps from the commercially available (±)-3-hydroxypyrrolidine hydrochloride (2a). The key steps include the direct oxidation of (±)-2a to (±)-3-hydroxy-1-pyrroline N-oxide (1a) using the Davis reagent and the domino reaction; viz., the lipase-catalyzed dynamic kinetic resolution of (±)-1a with 1-ethoxyvinyl ethyl maleate followed by the intramolecular [3+2] dipolar cycloaddition reaction of the generated optically active ester. Some insights into the mechanism of the racemization of the optically active 1a, observed during the enzymatic process, were also obtained.  相似文献   
119.
Gas-phase E.P.R. spectra of the SH radical (2Π3/2) in the J = 5/2 and J = 3/2 rotational levels are described. Analysis of the hyperfine splittings gives the values of axial and non-axial components of the proton hyperfine interaction and the value of the constant d. The frequencies of the two strong lines in the zero-field spectrum are estimated by the use of the observed value of the hyperfine interaction constant d.  相似文献   
120.
Generation of 1,2-ethanbis(trithiocarbonic acid) dianion from 2,2′-[1,2-ethanediylbis (thio)]bis-1,3-dithiolane and its reaction with alkyl halldes were investigated.  相似文献   
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