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We analyze the dynamics of an AdS5 braneworld with matter fields when gravity is allowed to deviate from the Einstein form on the brane. We consider exact five-dimensional warped solutions which are associated with conformal bulk fields of weight –4 and describe on the brane the following three dynamics: those of inhomogeneous dust, of generalized dark radiation, and of homogeneous polytropic dark energy. We show that, with modified gravity on the brane, the existence of such dynamical geometries requires the presence of non-conformal matter fields confined to the brane. 相似文献
4.
Polypropylene (PP) was modified with elastomer or CaCO3 particles of two different sizes (1 μm and 50 nm) in various volume fractions. The dispersion morphology and mechanical properties of the two systems were investigated as functions of the particle size and volume fraction of the modifier. The brittle‐to‐tough transition occurred when the matrix ligament thickness was less than the critical ligament thickness, which was about 0.1 μm for the PP used here, being independent of the type of modifier. At the same matrix ligament thickness, the improvement of the toughness was obviously higher with the elastomer rather than with CaCO3, but adding CaCO3 increased the modulus of PP. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1656–1662, 2004 相似文献
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The aim of this paper is to present construction of finite element multiscaling function with three coefficients. In order to illuminate the result, two examples are given finally. 相似文献
7.
利用傅里叶变温红外光谱仪分别测定了三羟甲基甲胺(TAM)、季戊四醇(PE)及其二元体系变温红外谱。实验表明,多元醇分子中羟基吸收峰随温度升高耐发生位移向高波数移动,此结果既能反映多元醇及其二体系固-固相变的温度区间,又与转变热相对应,从而揭示了多元醇及其二元体系固-固相变贮热的机理。 相似文献
8.
Y. D. Kolekar S. B. Kulkarni Keka Chakraborty A. Das S. K. Paranjpe P. B. Joshi 《Pramana》2004,63(2):189-197
Nd2Sn2O7 pyrochlores with the substitution of Zr4+ were prepared by conventional ceramic double sintering technique. The single-phase formation was confirmed by X-ray diffraction
and neutron diffraction techniques. Relative intensity calculations for X-ray diffraction analysis were performed for oxygen
positional parametersx = 0.331 and 0.375, while Rietveld refinements were employed for neutron diffraction data. The neutron diffraction study revealed
that there are only two anion sites with 48f and 8b positions. This indicates that the 8a site, i.e. O(3) sublattice, is completely
vacant and the structure is a perfect cubic pyrochlore with space group Fd3m (O
h
7
). From the conductivity measurements, it is observed that the electronic conductivity dominates from room temperature up
to about 525 K and forT > 525 K, the oxygen ion conduction dominates the charge transport in these compositions. Complex impedance spectroscopy indicates
the existence of grain and grain boundary as two separate elements. 相似文献
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In this talk, the interaction of a single photon injected to a single atom is studied, for which initially the photon is uncorrelated with the atom. The spontaneous emitted photon will then evolve to be entangled with the atom on their continuous kinetic variables (momentum) in the process of resonant scattering. We find the relations between the entanglement and their physical control parameters (such as the linewidth of the injected photon wave packet, and that of the atomic wave packet, etc. ), which indicates that high entanglement can be reached by broadening the scale of the atomic wave or squeezing the linewidth of the incident single-photon pulse. 相似文献