Anyonic Excitations in Fast Rotating Bose Gases Revisited

The role of anyonic excitations in fast rotating harmonically trapped Bose gases in a fractional Quantum Hall state is examined. Standard Chern-Simons anyons as well as "non standard" anyons obtained from a statistical interaction having Maxwell-Chern-Simons dynamics and suitable non minimal coupling to matter are considered. Their respective ability to stabilize attractive Bose gases under fast rotation in the thermodynamical limit is studied. Stability can be obtained for standard anyons while for non standard anyons, stability requires that the range of the corresponding statistical interaction does not exceed the typical wavelenght of the atoms.Comment: 5 pages. Improved version to be published in Phys. Rev. A, including a physical discussion on relevant interactions and scattering regime together with implication on the nature of statistical interactio

On the Class of Possible Nonlocal Anyon-Like Operators and Quantum Groups

We find a class of nonlocal operators constructed by attaching a disorder operator to fermionic degrees of freedom, which can be used to generate q-deformed algebras following the Schwinger approach. This class includes the recently proposed anyonic operators defined on a lattice.Comment: 10 pages (plain latex), HU-SEFT R 1993-9, to be published in Journal of Physics A: Math. and General, Letters to the Edito

Quasi-Continuous Symmetries of Non-Lie Type

We introduce a smooth mapping of some discrete space-time symmetries into quasi-continuous ones. Such transformations are related with q-deformations of the dilations of the Euclidean space and with the non-commutative space. We work out two examples of Hamiltonian invariance under such symmetries. The Schrodinger equation for a free particle is investigated in such a non-commutative plane and a connection with anyonic statistics is found.Comment: 18 pages, LateX, 3 figures, Submitted Found. Phys., PACS: 03.65.Fd, 11.30.E

Vortex in Maxwell-Chern-Simons models coupled to external backgrounds

We consider Maxwell-Chern-Simons models involving different non-minimal coupling terms to a non relativistic massive scalar and further coupled to an external uniform background charge. We study how these models can be constrained to support static radially symmetric vortex configurations saturating the lower bound for the energy. Models involving Zeeman-type coupling support such vortices provided the potential has a "symmetry breaking" form and a relation between parameters holds. In models where minimal coupling is supplemented by magnetic and electric field dependant coupling terms, non trivial vortex configurations minimizing the energy occur only when a non linear potential is introduced. The corresponding vortices are studied numericallyComment: LaTeX file, 2 figure

Dissolved organic carbon retention by coprecipitation during the oxidation of ferrous iron (EGU2018-3906)

Although the importance of Fe (hydr)oxides for soil organic matter (OM) stabilization and C retention by surface adsorption is well known, only recently has coprecipitation been recognized as an important process responsible for C storage in hydromorphic soils, such as rice paddy soils. Under periodic fluctuations in redox conditions the interaction between dissolved organic carbon (DOC) and Fe (hydr)oxides may not only involve organic coatings on mineral surfaces, but also Fe-DOC coprecipitates that form during the oxidation of soil solutions containing important amounts of DOC and Fe2+. The aim of this work was to provide new insights into the mechanisms involved, and the amount and selectivity of C retained during the coprecipitation process. A series of Fe-OM associations with increasing C loading was synthesized at pH 6 by surface adsorption or coprecipitation (oxidation of ferrous iron) utilizing rice-straw derived dissolved organic matter. The kinetics of Fe2+ oxidation and complexation, and the total and selective retention of DOC during the coprecipitation process were evaluated. Moreover, synthesized associations, as well as a field coprecipitate collected in situ from a paddy soil, were studied by X-ray diffraction, N2 gas adsorption-desorption isotherms, electrophoretic mobility measurements and thermogravimetric analyses. Coprecipitation resulted in higher organic C contents (49-213 mg g-1) with respect to adsorbed systems (18-47 mg g-1), and favoured the inclusion of OM within highly aggregated associations having particularly low BET specific surface areas. Coprecipitates sampled in situ also showed a similar retention of organic C confirming that this process may contribute significantly to the OM stabilization in paddy topsoils. The mechanisms involved in the retention of straw-derived DOM during coprecipitation were shown to be strongly dependent on C/Fe ratio of the solution. Although the overall coprecipitation process was highly selective for aromatic constituents, initial complexation of Fe2+ and precipitation as C-rich metal salts involved the selective interaction with aliphatic carboxylic constituents. The contribution of the latter mechanism to total C retention during coprecipitation was shown to increase with increasing solution C/Fe ratios. These aliphatic complexes formed during coprecipitation may play an important, though often underestimated, role in C stabilization in hydromorphic. The process-related selectivity of specific constituents of DOM during coprecipitation highlights the involvement of specific mechanisms, i.e. complexation, adsorption, salt precipitation, while ruling out non-selective, physical occlusion of OM within the forming coprecipitat

Generalized exclusion and Hopf algebras

We propose a generalized oscillator algebra at the roots of unity with generalized exclusion and we investigate the braided Hopf structure. We find that there are two solutions: these are the generalized exclusions of the bosonic and fermionic types. We also discuss the covariance properties of these oscillatorsComment: 10 pages, to appear in J. Phys.

Incidence of particle size distribution in peanut husks bonded panels

El propósito de esta etapa de la investigación fue conocer la influencia de la variación del tamaño y de la forma de partículas cáscaras de maní en las propiedades de paneles aglomerados encolados con resina ureica. Se formularon paneles con cáscaras molidas (densidad de las partículas: de 81 Kg/m3), paneles con cáscaras enteras (densidad de las partículas: 200 Kg/m3) y dos combinaciones de las mismas. Los resultados alcanzados demostraron que los paneles compuestos por partículas de cáscaras de maní molidas (finas) mejoraron las propiedades físicas y mecánicas respecto de las placas que incorporaron partículas de mayor tamaño. Los valores de densidad en paneles con partículas molidas fueron 628,67 Kg/m3; absorción de agua 65,3% y 79,75% a 2 h y 24 h respectivamente; e hinchamiento de 9,9% y 14,35% medidos a 2 h y 24 h respectivamente. En relación a la caracterización de propiedades mecánicas de flexión, los valores registrados en muestras elaboradas con partículas finas de cáscaras de maní resultaron en MOR: 3,58 MPa, LOP 2,26 MPa y MOE 627 MPa. Con respecto a tenacidad, el mayor valor fue observado en los tableros elaborados con partículas enteras de cáscaras de maní: 1,58 MPa. Las propiedades caracterizadas se encuentran aun por debajo de las propiedades de las placas comerciales de madera de tipo MDF y aglomerados convencionales. Ajustes al proceso de elaboración de las placas de cáscaras de maní serán incorporados en futuros trabajosThe purpose of this stage was to determine the influence of particle size and shape of peanut husks on the properties of panels made with urea resin. Panels were made with milled husks200 Kg/m3 ) and unmilled husks (81 Kg/m3 ) and two combinations thereof. The results showed that the panels made with milled husks improved physical and mechanical properties with respect to the panels that incorporated unmilled particles. The density values in panels with milled particles were 628.67 Kg / m3 ; water absorption 65.3% and 79.75% at 2 and 24 hours respectively, and swelling of 9.9% and 14.35% measured at 2 and 24 hours respectively. Regarding the characterization of mechanical properties of bending, the values recorded in samples prepared with fine particles of peanut husks resulted in MOR: 3.58 MPa, LOP 2.26 MPa and MOE 627 MPa. With respect to toughness, the highest value was observed in particle boards made from unmilled peanut husks: 1.58MPa. The characterized properties are still below the properties of commercial wood panels. Adjustments to the process of preparing the peanut husks plates will be incorporated in future experiencesFil: Granero, Ana Victoria. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); ArgentinaFil: Gatani, Mariana Pilar. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); ArgentinaFil: Medina, J. C. Universidad Nacional de Santiago del Estero. Facultad de Cs.forestales. Instituto de Tecnologia de la Madera; ArgentinaFil: Ruiz, A.. Universidad Nacional de Santiago del Estero. Facultad de Cs.forestales. Instituto de Tecnologia de la Madera; ArgentinaFil: Fiorelli, J.. Universidade de Sao Paulo; Brasil. Laboratorio de Construções e Ambiência. Faculdade de Zootecnia e Enghenaria de Alimentos; BrasilFil: Kreiker, Jeronimo Rafael. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); ArgentinaFil: Lerda, Maria Josefina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); Argentin