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51.
Let B⊆A be an H-Galois extension, where H is a Hopf algebra over a field K. If M is a Hopf bimodule then , the Hochschild homology of A with coefficients in M, is a right comodule over the coalgebra CH=H/[H,H]. Given an injective left CH-comodule V, our aim is to understand the relationship between and . The roots of this problem can be found in Lorenz (1994) [15], where and are shown to be isomorphic for any centrally G-Galois extension. To approach the above mentioned problem, in the case when A is a faithfully flat B-module and H satisfies some technical conditions, we construct a spectral sequence
52.
Martin Bordemann Abdenacer Makhlouf 《International Journal of Theoretical Physics》2008,47(2):311-332
We describe enveloping algebras of finite-dimensional Lie algebras which are formal in the sense that their Hochschild complex
as a differential graded Lie algebra is quasi-isomorphic to its Hochschild cohomology. For Abelian Lie algebras this is true
thanks to the Kontsevich formality theorem. We are using his formality map twisted by the group-like element generated by
the linear Poisson structure to simplify the problem, and then study examples. For instance, the universal enveloping algebras
of the Lie algebras
are formal. We also recover our rigidity results for enveloping algebras from this new angle and present some explicit deformations
of linear Poisson structure in low dimensions. 相似文献
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Thermally-evaporated thin films of tetraphenylporphyrin, TPP, with thickness range from (175 to 735) nm had been prepared. Annealing temperatures ranging from (273–473) K do not influence the amorphous structure of these films. The influence of environmental conditions: film thickness, temperature and frequency on the electrical properties of TPP thin films had been reported. It was found that dc conductivity increases with increasing temperature and film thickness. The extrinsic conduction mechanism is operating in temperature range of (293–380) K with activation energy of 0.13 eV. The intrinsic one is in temperatures >380 K via phonon assisted hopping of small polaron with activation energy of 0.855 eV. The ac electrical conductivity and dielectric relaxation in the temperature range (293–473) K and in frequency range (0.1–100) kHz had been also studied. It had been shown that theoretical curves generated from correlated barrier hopping (CBH) model gives the best fitting with experimental results. Analysis of these results proved that conduction occurs at low temperatures (300–370) K by phonon assisted hopping between localized states and it is performed by single polaron hopping process at higher temperatures. The temperature and frequency dependence of both the real and imaginary parts of dielectric constant had been reported. 相似文献
56.
In this article, we obtain the weak and strong rates of convergence of time integrals of non-smooth functions of a one dimensional diffusion process. We propose the use of the exact simulation scheme to simulate the process at discretization points. In particular, we also present the rates of convergence for the weak and strong errors of approximation for the local time of a one dimensional diffusion process as an application of our method. 相似文献
57.
M. Boudjema-Bouloudenine T. Boudjedaa A. Makhlouf 《The European Physical Journal C - Particles and Fields》2006,46(3):807-816
We have applied the Schwinger action principle to general one-dimensional (1D), time-dependent quadratic systems via linear
quantum canonical transformations, which allowed us to simplify the problems to be solved by this method. We show that while
using a suitable linear canonical transformation, we can considerably simplify the evaluation of the propagator of the studied
system to that for a free particle. The efficiency and exactness of this method is verified in the case of the simple harmonic
oscillator. This technique enables us to evaluate easily and immediately the propagator in some particular cases such as the
damped harmonic oscillator, the harmonic oscillator with a time-dependent frequency, and the harmonic oscillator with time-dependent
mass and frequency, and in this way the propagator of the forced damped harmonic oscillator is easily calculated without any
approach.
PACS 02.30.Xx, 03.65.-w, 03.65.Ca 相似文献
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Amel Boulfoul Amar Makhlouf Nawal Mellahi 《Journal of Applied Analysis & Computation》2019,9(3):864-883
In this paper, we consider the limit cycles of a class of polynomial differential systems of the form $\dot{x}=-y, \hspace{0.2cm} \dot{y}=x-f(x)-g(x)y-h(x)y^{2}-l(x)y^{3},$ where $f(x)=\epsilon f_{1}(x)+\epsilon^{2}f_{2}(x),$ $g(x)=\epsilon g_{1}(x)+\epsilon^{2}g_{2}(x),$ $h(x)=\epsilon h_{1}(x)+\epsilon^{2}h_{2}(x)$ and $l(x)=\epsilon l_{1}(x)+\epsilon^{2}l_{2}(x)$ where $f_{k}(x),$ $g_{k}(x),$ $h_{k}(x)$ and $l_{k}(x)$ have degree $n_{1},$ $n_{2},$ $n_{3}$ and $n_{4},$ respectively for each $k=1,2,$ and $\varepsilon$ is a small parameter. We obtain the maximum number of limit cycles that bifurcate from the periodic orbits of the linear center $\dot{x}=-y,$ $\dot{y}=x$ using the averaging theory of first and second order. 相似文献
60.
P. P. George A. Gedanken Shirly Ben-David Makhlouf I. Genish A. Marciano Riam Abu-Mukh 《Journal of nanoparticle research》2009,11(4):995-1003
TiN, NbN, and TaN nanocrystals have been selectively prepared through a simple, solvent-free, and convenient reaction under
autogenic pressure at moderate temperature (RAPET) process at 350 °C for 12 h, reacting transition metal chlorides and sodium
azide. The nanostructures obtained are characterized by powder X-ray diffraction (PXRD), transmission electron microscopy
(TEM), and scanning electron microscopy (SEM). A reaction mechanism is suggested based on the experimental results. These
rapid reactions produce nanocrystals of TiN, NbN, and TaN with average sizes of approximately 30, 28, and 27 nm, respectively
(as calculated from X-ray line broadening). An octahedral inorganic fullerene was detected among the various structures of
the TiN. 相似文献