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201.
Recently Yang et al. (Int. J. Theor. Phys. 48:516, 2009) had shown that using a particular type of GHZ- Like state as quantum channel, it is possible to teleport an arbitrary unknown qubit. We investigate this channel for the teleportation of a particular type of two qubit state.  相似文献   
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The present compound crystallizes in the space groupP212121 withZ=4 and cell parametersa=21.687(2),b=8.155(3),c=5.883(2)Å. The structure was solved by direct methods and refined by full-matrix least-squares to a finalR value of 0.045 for 1153 observed reflections. The N-glycosidic torsion angle CN is in the anti-range and the pyranosyl ring adopts a distorted half-chair conformation with 2=142.7(4)°, 2=124.4(3)° andQ=0.456(2)Å. In the crystal packing the molecules are linked together by N-HO hydrogen bonds and C-HO contacts.  相似文献   
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A thin viscous liquid film flow is developed over a stretching sheet under different nonlinear stretching velocities. An evolution equation for the film thickness, is derived using long-wave approximation of thin liquid film and is solved numerically by using the Newton–Kantorovich method. A comparison is made with the analytic solution obtained in [B. S. Dandapat, A. Kitamura, B. Santra, “Transient film profile of thin liquid film flow on a stretching surface”, ZAMP, 57, 623-635 (2006)]. It is observed that all types of stretching produce film thinning but non-monotonic stretching produces faster thinning at small distance from the origin. The velocity u along the stretching direction strongly depends on the distance along the stretching direction and the Froude number.  相似文献   
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In this paper we study the asymptotics of the tail of the buffer occupancy distribution in buffers accessed by a large number of stationary independent sources and which are served according to a strict HOL priority rule. As in the case of single buffers, the results are valid for a very general class of sources which include long-range dependent sources with bounded instantaneous rates. We first consider the case of two buffers with one of them having strict priority over the other and we obtain asymptotic upper bound for the buffer tail probability for lower priority buffer. We discuss the conditions to have asymptotic equivalents. The asymptotics are studied in terms of a scaling parameter which reflects the server speed, buffer level and the number of sources in such a way that the ratios remain constant. The results are then generalized to the case of M buffers which leads to the source pooling idea. We conclude with numerical validation of our formulae against simulations which show that the asymptotic bounds are tight. We also show that the commonly suggested reduced service rate approximation can give extremely low estimates.  相似文献   
206.
A Study of electronic conductivity using the d.c. polarization technique has been carried out in α and β-AgI which shows the former is a hole and the latter an electron conductor. Activation energies of undoped and Cu-doped single crystals and polycrystalline β-AgI were found to be 0.46 eV, 0.34 eV and 0.44 eV respectively and can be related to electron trap depths. The electron transference number (σθσt) for polycrystalline β-AgI was found to be 0.008 at 306 K. The activation energy for hole conduction in α-AgI was determined to be 0.97 eV in agreement with previous XPS studies.Transient measurements have also been conducted using the charge transfer technique in double cells of polycrystalline β-AgI. The carrier concentration Cθ and electron mobility μθ, have thus been estimated to be 1.8 × 1015cm3 and 5.14 × 10?5cm2V?sec. respectively at 306 K, while the double layer capacitance was 0.496 μFcm2.  相似文献   
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A method for the time history of motion of shallow shells of viscoelastic material under arbitrary time-dependent transverse load is presented. The method is based upon the concept of iso-amplitude contour lines on the surface of the shell. It is shown that the time behavior can be found by using the frequency of free vibration of the associated elastic shallow shell. As an illustration of the technique, the problem of a shallow dome upon an elliptic base is discussed, all details of which are explained by graphs.  相似文献   
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We discuss a unique possibility of generating adiabatic density perturbations and leptogenesis from the spatial fluctuations of the inflaton decay rate. The key assumption is that the initial isocurvature perturbations are created in the right-handed sneutrino sector during inflation which is then converted into adiabatic perturbations when the inflaton decays. We discuss distinct imprints on the cosmic microwave background radiation, which can distinguish nonthermal versus thermal leptogenesis.  相似文献   
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