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91.
92.
We consider the derivative nonlinear Schrödinger equations


where the coefficient satisfies the time growth condition


is a sufficiently small constant and the nonlinear interaction term consists of cubic nonlinearities of derivative type

where and . We suppose that the initial data satifsfy the exponential decay conditions. Then we prove the sharp decay estimate , for all , where . Furthermore we show that for there exist the usual scattering states, when and the modified scattering states, when

  相似文献   

93.
Using a newly developed laser-microwave-laser resonance method, we observed a pair of microwave transitions between hyperfine levels of the (n,L)=(37,35) state of antiprotonic helium. This experiment confirms the quadruplet hyperfine structure arising from the interaction of the antiproton orbital angular momentum, the electron spin and the antiproton spin as predicted by Bakalov and Korobov. The measured frequencies of nu(+)(HF)=12.895 96+/-0.000 34 GHz and nu(-)(HF)=12.924 67+/-0.000 29 GHz agree with recent theoretical calculations on a level of 6x10(-5).  相似文献   
94.
Initial distributions of metastable antiprotonic (4)He and (3)He atoms over principal (n) and angular momentum (l) quantum numbers have been deduced using laser spectroscopy experiments. The regions n = 37-40 and n = 35-38 in the two atoms account for almost all of the observed fractions [(3.0 +/- 0.1)% and (2.4 +/- 0.1)%] of antiprotons captured into metastable states.  相似文献   
95.
We report Cd nuclear magnetic resonance (NMR) and Re nuclear quadrupole resonance (NQR) studies on Cd(2)Re(2)O(7), the first superconductor among pyrochlore oxides (T(c) approximately 1 K). The Re NQR spectrum at zero magnetic field below 100 K rules out any magnetic or charge order. The spin-lattice relaxation rate below T(c) exhibits a pronounced coherence peak and follows the weak-coupling BCS theory with nearly isotropic energy gap. The results of Cd NMR point to a moderate ferromagnetic enhancement at high temperatures followed by a rapid decrease of the density of states below the structural transition temperature of 200 K.  相似文献   
96.
Kelvin probe force microscopy (KFM) and conductive atomic force microscopy (C‐AFM) together with micro X‐ray photoelectron spectroscopy (XPS) were performed for the stacking structure comprising of the transition metal oxide Co–O and metal electrode, which exhibits large reproducible resistance switching. The application of the external voltage by the C‐AFM cantilever decreases the resistance of Co–O, which well accords with the non‐polar forming process observed in the Pt/Co–O/Pt trilayer, known as the candidate of resistance random access memory (ReRAM). Furthermore, the KFM and micro XPS experimentally revealed that the local reductive reaction of Co–O possibly nucleates the defect related energy levels which dominates the current conduction in the low resistance state. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
97.
For an element of the Brauer group of a curve over a local field, we define the ``Swan conductor' of , which measures the wildness of the ramification of . We give a relation between and Swan conductors for Brauer groups of henselian discrete valuation fields defined by Kato.

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98.
99.
Then th,α)-reaction spectroscopical data are reported on95Mo,123Te and145Nd (target nuclei). The95Mo(n, α)92Zr and123Te(n, α)120Sn reactions showed up two lines each corresponding to the ground state and the 1st excited state with a total cross section of 32 ub and 52 μb respectively. In the case of145Nd(n, α)142Ce, a transition only to the 1st excited state of142Ce is present. It is shown that in the case of95Mo,145Nd and probably123Te, most of the cross-section comes respectively from the 2+ possibly 4?, and 0 bound levels whose widths are determined to beΓ α=0.5 × 10?6 eV,Γ α=1.6×10?8 eV andΓ α=1.6 × 10?6 eV. The present results on these three nuclei, when combined with the existing data, are consistent with the calculated statistical model values.  相似文献   
100.
A new method for determining absolute photoionization cross sections for gaseous compounds is proposed. In this method a mixture of a sample and a standard gas (N2) is used in photoelectron intensity measurements so that the relative intensity of the component is obtained with respect to N2 The relative photoelectron band area is converted to the absolute photoionization cross section on the basis of the absolute cross-section data of N2 recently reported by Samson et al. This method has been applied to various aliphatic compounds to study the effect of alkyl substitution on photoionization cross sections of O- and N-nonbonding electrons for 584-Å radiation.  相似文献   
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