654 research outputs found
Effects of Lorentz violation in the Bose-Einstein condensation
In this paper we study the corrections emergent from a Lorentz-violating
CPT-odd extension of the complex scalar sector to the Bose-Einstein
condensation and to the thermodynamics parameters. We initially discussed some
features of the model to only then compute the corrections to the Bose-Einstein
condensation. The calculations were done by computing the generating
functional, from which we extract the thermodynamics parameters. We also
obtained a Lorentz-violating correction for the critical temperature that
sets the Bose-Einstein Condensation.Comment: 6 pages. 2 figures. Version accepted by EPL. Minor typo corrections.
arXiv admin note: text overlap with arXiv:2009.0230
Dressing approach to the nonvanishing boundary value problem for the AKNS hierarchy
We propose an approach to the nonvanishing boundary value problem for
integrable hierarchies based on the dressing method. Then we apply the method
to the AKNS hierarchy. The solutions are found by introducing appropriate
vertex operators that takes into account the boundary conditions.Comment: Published version Proc. Quantum Theory and Symmetries 7
(QTS7)(Prague, Czech Republic, 2011
Higher order effects in the and transfer reactions
Full Coupled Channels Calculations were performed for the
and transfer reactions at several deuteron incident
energies from MeV up to 3.27 MeV. A strong polarization effect
between the entrance channel and the transfer channels
and was
observed. This polarization effect had to be taken into account in order to
obtain realistic spectroscopic factors from these reactions.Comment: 15 papes, 13 figures, accepted for publication in Phys. Rev.
New extractants for separation of platinium-group metals from chloride solutions and their application to recycling processes
In this paper some results on the application of four N,N’-tetrasubstituted malonamide derivatives for the extraction and separation of platinum-group metals (PGMs) are presented. The above mentioned extractants were specifically synthesized in order to evaluate their efficiency for the extraction of a specific metal, or group of metals, from aqueous chloride matrices. Different behaviours were obtained towards platinum(IV) and/or palladium(II) extraction, all the N,N’-tetrasubstituted malonamide derivatives allowing the mutual separation of the two metal ions, depending on the HCl concentration. Generally, extraction experiments were carried out involving initial aqueous phases containing 100 mg/L of each metal isolate, in varying 1M to 8M HCl concentration ranges, and 0.05M extractant in 1,2- dichloroethane solutions. From the preliminary results obtained, one can conclude that HCl concentrations and the structure of the malonamide derivative play a crucial role on the efficiency shown for Pt(IV) and/or Pd(II) extraction. The efficiency of the stripping stage of the loaded organic phases is variable, depending on the N,N’-tetrasubstituted malonamide derivative, as well as on the metal ion involved; for Pt(IV), distilled water and 1M HCl were generally successful, whereas for Pd(II), thiourea in HCl gave better results. The overall data already achieved suggest that these extractants may be good candidates for further evaluation in PGMs separations from real solutions resulting from recycling processes
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