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31.
32.
Sansoni L Sciarrino F Vallone G Mataloni P Crespi A Ramponi R Osellame R 《Physical review letters》2012,108(1):010502
Quantum walk represents one of the most promising resources for the simulation of physical quantum systems, and has also emerged as an alternative to the standard circuit model for quantum computing. Here we investigate how the particle statistics, either bosonic or fermionic, influences a two-particle discrete quantum walk. Such an experiment has been realized by exploiting polarization entanglement to simulate the bunching-antibunching feature of noninteracting bosons and fermions. To this scope a novel three-dimensional geometry for the waveguide circuit is introduced, which allows accurate polarization independent behavior, maintaining remarkable control on both phase and balancement. 相似文献
33.
C. A. Ribeiro M. S. Crespi C. T. R. Guerreiro L. S. Guinesi 《Journal of Thermal Analysis and Calorimetry》2001,64(2):637-644
In this present work, barium ion was reacted with different ligands which are 5,7-dibromo 5,7-dichloro, 7-iodo and 5-chloro-7-iodo-8-hydroxyquinoline,
in acetone/ammonium hydroxide medium under constant stirring and the obtained compounds were as follows: (I) Ba[(C9 H4 ONBr2 )2 ]⋅1.5H2 O; (II) Ba[(C9 H4 ONCl2 )(OH)]⋅1H2 O; (III) Ba[(C9 H5 ONI)2 ]⋅1H2 O and (IV) Ba[(C9 H4 ONICl)2 ]⋅5H2 O, respectively. The compounds were characterized by elemental analysis, infrared absorption spectrum (IR), inductively coupled
plasma spectrometry (ICP), simultaneous thermogravimetry-differential thermal analysis (TG-DTA) and differential scanning
calorimeter (DSC).
The final residue of the thermal decomposition was characterized as orthorhombic BaBr2from (I); the intermediate residue, as a mixture of orthorhombic BaCO3 and BaCl2 and cubic BaO and the final residue, as a mixture of cubic and tetragonal BaO and orthorhombic BaCl2 (II); the intermediate residue, as orthorhombic BaCO3 and as a final residue, a mixture of cubic and tetragonal BaO from (III); and the intermediate residue, as a mixture of orthorhombic
BaCO3 and BaCl2 and as a final residue, a mixture of cubic and tetragonal BaO and orthorhombic BaCl2 from (IV).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
34.
35.
M. T. Valentini Ganzerli V. Crespi Caramella L. Maggi 《Journal of Radioanalytical and Nuclear Chemistry》2004,261(1):3-8
The adsorption conditions of uranium, neptunium, thorium, europium on the adsorbers containing the benzylate salts of the
8-hydroxyquinoline (adsorber B), and of 2-methyl- 8-hydroxyquinoline (adsorber R), were prepared, supported onto charcoal
and compared with an adsorber, containing the benzylic acid, (G), stabilized with d-glucoseamine, and adsorbed onto charcoal
as well. Thorium, protoactinium, and europium are adsorbed nearly completely from aqueous solutions at a large pH range, even
in low acid medium, whereas uranium and neptunium are completely adsorbed only from basic solutions of pH 9. The actinides
are preferentially adsorbed with respect to other ions, which are present in natural waters, such as calcium or magnesium.
This feature make the analysis of most actinides in natural waters easily to be performed without changing the pH of the original
system. The uranium (neptunium) analysis indeed may be accomplished after adjusting the original pH to a fairly basic value
(about to 9). The adsorption experiments from real samples showed that the analysis of the actinides dispersed in natural
water systems may be successfully performed after previous concentration on the adsorbers prepare.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
36.
Silva D. V. Ribeiro C. A. Crespi M. S. 《Journal of Thermal Analysis and Calorimetry》2003,72(1):151-157
Fluoride glasses have been extensively studied due to their high transparency in the infrared wavelength. The crystallization
kinetics of these systems has been studied using DTA and DSC techniques. Most of the experimental data is frequently investigated
in terms of the Johnson-Mehl-Avrami (JMA) model in order to obtain kinetic parameters. In this work, DSC technique has been
used to study the crystallization of fluorozirconate glass under non-isothermal conditions. It was found that JMA model was
not fit to be applied directly to these systems, therefore, the method proposed by Málek has been applied and the Šesták-Berggren
(SB) model seems to be adequate to describe the crystallization process.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
37.
A E Almeida A G Ferreira M S Crespi Z A Andrade M C Chung 《Journal of Thermal Analysis and Calorimetry》2006,83(2):277-281
Oxamniquine polymeric prodrug with potential antischistosomal
activity was prepared using dextran T-70 as a carrier, which was analysed
by 1HNMR, 13C NMR and
IR spectroscopy. The formation of the oxamniquine salt was confirmed by thermogravimetric
analysis (TG) and differential scanning calorimetry (DSC) which showed a different
thermal behaviour when compared to the physical mixture. 相似文献
38.
M. T. Valentini Ganzerli V. Crespi Caramella L. Maggi 《Journal of Radioanalytical and Nuclear Chemistry》2002,254(1):3-7
The Sun emits about 3.1043
1H per year in the solar wind (SW). Solar luminosity and the outflow of SW-protons come from the collapsed supernova core, a neutron star (NS), on which the Sun formed. The universal cradle of the nuclides indicates that the energy of each neutron in the Sun"s central NS exceeds that of a free neutron by »10–22 MeV. Solar luminosity and SW-protons are generated by a series of reactions: (a) escape of neutrons from the central NS, (b) decay of free neutrons or their capture by heavier nuclides, (c) fusion and upward migration of H+ through material that accreted on the NS, and (d) escape of H+ in the SW. 相似文献
39.
40.
Guerreiro C. T. R. Ribeiro C. A. Crespi M. S. 《Journal of Thermal Analysis and Calorimetry》2002,70(2):437-445
Metal complexes of calcium with 5,7-dibromo, 7-iodo and 5-chloro-7-iodo-8-hydroxyquinolate were precipitated in aqueous ammonia
and acetone medium, except for the solid state compound with 5,7-dichloro-8-hydroxyquinoline which hasn"t been obtained under
these conditions. The complexes obtained through the mentioned precipitation are Ca[(C9H4ONBr2)2]3·H2O, Ca[(C9H5ONI)2]·2H2O and Ca[(C9H4ONICl)2]·2.5H2O. Their intermediate from the thermal decomposition found through TG/DTA curves in air indicated the presence of different
kinds of calcium carbonates related to the reversibility and crystalline structure, depending on the original compounds. The
initial compounds and the intermediate from the thermal decomposition were also characterized through IR spectra and X-ray
diffraction.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献