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61.
62.
First are given results on the norm-continuity of translation semigroups and their asymptotic behavior. Secondly a cell cycle model is studied from the point of view of linear translation semigroups theory. Existence and norm-continuity of the solution semigroup and the property of exponential asynchronous growth are established for this model.  相似文献   
63.
In this work, we report on the structural characterisation of Ni and Ni/Ti bilayer contacts on n-type 4H-SiC. The redistribution of carbon, after annealing, in the Ni/SiC and the Ni/Ti/SiC contacts is particularly studied by RBS at 3.2 MeV, XRD and AES techniques.  相似文献   
64.
An experimental investigation is performed on a fully developed turbulent channel flow with local injection through a porous strip. The Reynolds number based on the channel half-width was set to 5000. In addition to the no blowing case, measurements are made for three different blowing rates σ = 0.22, 0.36 and 0.58 (where σ is the ratio of momentum flux gain due to the blowing and momentum flux of the incoming channel flow). Measurements carried out with hot-wire anemometry reveal that injection strongly affects both the velocity profiles and the turbulence characteristics. The injection decreases the skin friction coefficient and increases all the Reynolds stresses downstream the blowing strip. The turbulence structure and the bursting phenomena were examined using space-time correlations measurements and conditional analysis. It is found that the injection increases the frequency of occurrence of the bursts.  相似文献   
65.
We compare the effects of non-standard weak bosons (NSB) expected fromE 6-superstrings (Z′), strong Higgs (V 0) and composite (spin 0, 1, 2) models by using the classical inclusive deep-inelastic “ep” scattering at HERA energies. TheX 2 associated to polarized and unpolarized cross-sections, as well as the six combinations of asymmetries, allow us to derive significant bounds on the masses of the new bosons of various spins associated to some composite models with exception of the excitedZ *. We have also obtained some lower bounds for spin one bosons of different models (Z′,V 0,Z *) which are stronger than the present experimental limits.  相似文献   
66.
In this study, we report on the structural characterization of Ni layer and Ni/Ti bilayer contacts on n-type 4H-SiC. The resulting Ni-silicides and the redistribution of carbon, after annealing at 950 °C, in the Ni/SiC and the Ni/Ti/SiC contacts are particularly studied by Rutherford Backscattering Spectrometry (RBS) at Eα = 3.2 MeV, nuclear reaction analysis (NRA) at Ed = 1 MeV, scanning electron microscopy (SEM) and Energy Dispersive X-ray Spectrometry (EDS) techniques.  相似文献   
67.
We present in this paper a consistent nonparametric test for heteroscedasticity when data are of functional kind. The latter is constructed by evaluating the difference between the conditional and unconditional variances. We show the asymptotic normality of the statistical test under the null hypothesis. In addition, we prove that this test is consistent against all deviations from homoscedasticity condition.  相似文献   
68.
Plasma Chemistry and Plasma Processing - The paper presents an experimental and theoretical study of the radiative emission in the pure krypton lamp excited by dielectric barrier discharge....  相似文献   
69.
The stability of second order abstract distributed systems with damping and nonlinear perturbations is considered. Sufficient conditions, including unique continuation property assumptions, are formulated to obtain (local, non-uniform and uniform) exponential stability. Applications to the wave and Euler-Bernoulli equations are given.  相似文献   
70.
Simultaneous determination of N, Mg, Al, Si, P, Cl, K, Ca and Fe in chicken dung and dates was carried out using fast neutron activation analysis (FNAA) with a SAMES J25 neutron generator. The activities were measured with a 72 cm3 high purity germanium detector using the relative method. The accuracy was checked with the aid of a standard reference material of milk powder A11 supplied by the IAEA. For the nitrogen contents, the results were compared to those obtained by the classical KJELDAHL method.  相似文献   
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