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51.
We investigate multiple linear optical teleportation in the Knill-Laflamme-Milburn scheme with both maximally and nonmaximally entangled states. We show that if the qubit is teleported several times via a nonmaximally entangled state, then the errors introduced in the previous teleportations can be corrected by the errors introduced in the following teleportations. This effect is so strong that it leads to another interesting phenomenon: i.e., the total probability of successful multiple linear optical teleportation is higher for nonmaximally entangled states than maximally entangled states.  相似文献   
52.
We present a new phase element which has the same optical properties as those of the amplitude sampling filter but it can use theoretically all the incident light for multiple image formation. The paper discusses a design method of the element and a diffraction efficiency of its structure obtained in a lithographic process. Then the quality and imaging ability of a phase element, fabricated according to the described design, are verified in an optical set-up.  相似文献   
53.
54.
By combining ab initio results for the electronic structure and phonon spectrum with the group theory, we establish the origin of the Verwey transition in Fe3O4. Two primary order parameters with X3 and Delta5 symmetries are identified. They induce the phase transformation from the high-temperature cubic to the low-temperature monoclinic structure. The on-site Coulomb interaction U between 3d electrons at Fe ions plays a crucial role in this transition--it amplifies the coupling of phonons to conduction electrons and thus opens a gap at the Fermi energy.  相似文献   
55.
We review evolution equations for the truncated Mellin moments of the parton distributions and some their applications in QCD analysis. The main finding of the presented approach is that the nth truncated moment of the parton distribution obeys also the DGLAP equation but with a rescaled splitting function P′(z) = z n P(z). This allows one to avoid the problem of dealing with the experimentally unexplored Bjorken-x region. The evolution equations for truncated moments are universal—they are valid in each order of perturbation expansion and can be useful additional tool in analysis of unpolarized as well as polarized nucleon structure functions.  相似文献   
56.
We show that it is possible to play ‘restricted’ two-player quantum games proposed originally by Marinatto and Weber (Phys. Lett. A 272:291–303, 2000) by purely macroscopic means, in the simplest case having as the only equipment a pack of 10 cards. Our example shows also that some apparently ‘genuine quantum’ results, even those that emerge as a consequence of dealing with entangled states, can be obtained by suitable application of Kolmogorovian probability calculus and secondary-school mathematics, without application of the ‘Hilbert space machinery’.  相似文献   
57.
58.
In the paper calculation of the moments of inertia for nuclei from the region 87 ≤ Z ≤ 100 and 130 ≤ N ≤ 156 was made in dependence on the angular momentum of their rotational states. The experimental values of the moments of inertia were calculated for rotational energy of the classic rotor in its quantum form, with the use of a simple formula. The moment of inertia term appearing in the formula was treated as a variable. The calculations were carried out on the basis of experimental data for the energies of the rotational levels for 51 bands built on ground states for even-even nuclei and for nuclei with odd mass number A. In addition, 30 rotational bands built on excited states were also analysed in the investigated region in case of even-even nuclei. For many bands and nuclei the considered dependence of the moment of inertia on angular momentum has been found in the analytical form by fitting polynomials to the experimental data. It turned out that obtained results for the moments of inertia made it possible to describe the energies of rotational levels with a relative deviation not greater or only slightly greater than 1%. In general, in the case of 12 bands of ground level the maximum relative deviation of obtained level energies is smaller than 1%.   相似文献   
59.
Tubular arrays of TiO2 nanotubes (ranging in diameter from 40 to 110 nm) on a Ti substrate were used as a support for Ag, Au or Cu deposits obtained by the sputter deposition technique, where the amount of metal varied from 0.01 to 0.2 mg/cm2. Those composite supports were intended for surface-enhanced Raman scattering (SERS) investigations. Composite samples were studied with the aid of scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) to reveal their characteristic morphological and chemical features. Raman spectra of pyridine (as a probe molecule) were measured at different cathodic potentials ranging from −0.2 down to −1.2 V after the pyridine had been adsorbed on the metal-covered TiO2 nanotube/Ti substrates. In addition, SERS spectra on a bulk standard activated Ag, Au and Cu substrates were also measured. The SERS activity of the composite samples was strongly dependent on the amount of metal deposit, e.g. at and above 0.06 mg Ag/cm2, the intensity of SERS signal was even higher than that for the Ag reference substrate. The high activity of these composites is mainly a result of their specific morphology. The high SERS sensitivity on the surface morphology of the substrate made it possible to monitor very small temporal changes in the Ag metal clusters. This rearrangement was not detectable with microscopic (SEM) or microanalytical (AES) methods. The SERS activity of Au or Cu clusters was distinctly lower than those of Ag. The spectral differences exhibited by the three kinds of composites as compared to the reference metal samples are discussed.  相似文献   
60.
The creation of multifunctional nanomaterials by combining organic and inorganic components is a growing trend in nanoscience. The unique size-dependent properties of magnetic nanoparticles (MNPs) make them amenable to numerous applications such as carriers of expensive biological catalysts, in magnetically assisted chemical separation of heavy metals and radionuclides from contaminated water sources. The separation of minor actinides from high-level radionuclide waste requires a sorbent stable in acidic pH, with ease of surface functionalization, and a high capacity for binding the molecules of interest. For the described experiments, the MNPs with 50 nm average size were used (size distribution from 20 to 100 nm and an iron content of 80–90 w/w%). The MNPs that have been double coated with an initial silica coating for protection against iron solubilization and oxidation in nitric acid solution (pH 1) and a second silica/polymer composite coating incorporating partially imbedded poly(allylamine) (PA). The final product is magnetic, highly swelling, containing >95% water, with >0.5 mmol amines g?1 available for functionalization. The amine groups of the magnetic resin were functionalized with the chelating molecules diethylenetriaminepentaacetic acid (DTPA) and N,N-dimethyl-3-oxa-glutaramic acid (DMOGA) for separation of minor actinides from used nuclear fuel.  相似文献   
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