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61.
E.C. Paris M.F.C. Gurgel G.P. Casali T.M. Boschi J.A. Varela 《Journal of Physics and Chemistry of Solids》2010,71(1):12-17
Pb1−xSmxTiO3 (PST) powders with x varying from 0 to 0.1 were obtained by the polymeric precursor method, a soft chemical route. The vibrational properties relating tetragonal to pseudo-cubic phase transition were studied by Raman spectroscopy. The results obtained showed that the phase transition is extremely dependent upon the samarium content and presents a diffuse behavior. Monitoring of the oxygen 2p and titanium 3d orbitals was performed by the periodic mechanical quantum method, revealing the changes that occur with the distribution and contribution of the hybrid orbitals due to the samarium influence. 相似文献
62.
We address the dynamics of entanglement transfer from
two radiation modes to a pair of localized qubits implemented as
atoms flying through or trapped in separated cavities. We first
generalize previous results to include radiation in entangled
mixed states and to describe the effect of cavity mirror
transmittance. Then we investigate the transfer process by Monte
Carlo Wave Function approach, which allows us to solve the whole
system dynamics including cavity mode and atomic decays. We focus
on flying modes prepared in coherently correlated states and we
find realistic conditions for efficient entanglement transfer out
of the weak and strong coupling regimes in the perspective of
quantum memories realization. 相似文献
63.
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66.
Continuous separation of lipid particles from erythrocytes by means of laminar flow and acoustic standing wave forces 总被引:1,自引:0,他引:1
Improved continuous acoustic particle separation (separation efficiency close to 100%) and separation of erythrocytes (red blood cells) from lipid microemboli in whole blood is reported. 相似文献
67.
Primary- and secondary-alkyl aryl tellurides, prepared by arenetellurolate ring-opening of epoxides/ O-allylation, were found to undergo rapid (3-10 min) group-transfer cyclization to afford tetrahydrofuran derivatives in 60-74% yield when heated in a microwave cavity at 250 degrees C in ethylene glycol or at 180 degrees C in water. To go to completion, similar transformations had previously required extended photolysis in refluxing benzene containing a substantial amount of hexabutylditin. The only drawback of the microwave-assisted process was the loss in diastereoselectivity which is a consequence of the higher reaction temperature. Substitution in the Te-aryl moiety of the secondary-alkyl aryl tellurides (4-OMe, 4-H, 4-CF(3)) did not affect the outcome of the group-transfer reaction in ethylene glycol. However, at lower temperature, using water as a solvent, the CF(3) derivative failed to react. The microwave-assisted group-transfer cyclization was extended to benzylic but not to primary- and secondary-alkyl phenyl selenides. 相似文献
68.
Manetti C Castro C Zbilut JP 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,168(2):303-277
Determining the time constants and amplitudes of exponential decays from relaxation data is a common task in LF-NMR. In this communication, we present an application of the SLICING algorithm to evaluate its possibilities for solving this problem. The method, originally introduced to compare different samples, is applied here to analyse a single relaxation curve, using the embedding technique. To test this procedure, we acquired data sets from samples of liquids properly separated, and characterized by different relaxation times. The results show a good estimation of parameters, comparable with those obtained applying Marquardt's algorithm, when the components have sufficiently different relaxation times. 相似文献
69.
Peterson RW Anbalagan K Tommos C Wand AJ 《Journal of the American Chemical Society》2004,126(31):9498-9499
A significant fraction of the proteins encoded by the human and other genomes appears to be significantly unfolded in vitro. This will undoubtedly hamper attempts to characterize their structure by classical crystallographic or solution NMR methods. Here we show that encapsulation of a metastable protein within the restricted volume a reverse micelle can be used to force fold the protein and allow its characterization by modern methods of NMR spectroscopy. This may have significant utility in the context of structural proteomics. In addition, variation of the inner volume of the reverse micelle can be used to probe the character of the manifold of unfolded states. 相似文献
70.
Two-dimensional protein map of human vastus lateralis muscle 总被引:4,自引:0,他引:4
Protein samples of human vastus lateralis muscle were analyzed by two-dimensional gel electrophoresis, using immobilized pH gradients encompassing several pH regions in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the second dimension. More than 500 protein spots on each gel were detected by silver staining, of which 150 were excised, digested in-gel with trypsin and characterized by matrix assisted laser desorptioin/ionization-mass spectrometry and tandem electrospray mass spectrometry. Using these techniques, 124 spots including contractile proteins and metabolic enzymes were identified. This database should provide a valuable resource for the definition of the functional properties of muscle fibres and for assessment of the influence of e.g., hypoxia, ischaemia and ageing on protein level. 相似文献