4,096 research outputs found
Trajectories in a space with a spherically symmetric dislocation
We consider a new type of defect in the scope of linear elasticity theory,
using geometrical methods. This defect is produced by a spherically symmetric
dislocation, or ball dislocation. We derive the induced metric as well as the
affine connections and curvature tensors. Since the induced metric is
discontinuous, one can expect ambiguity coming from these quantities, due to
products between delta functions or its derivatives, plaguing a description of
ball dislocations based on the Geometric Theory of Defects. However, exactly as
in the previous case of cylindric defect, one can obtain some well-defined
physical predictions of the induced geometry. In particular, we explore some
properties of test particle trajectories around the defect and show that these
trajectories are curved but can not be circular orbits.Comment: 11 pages, 3 figure
Caracterização molecular e morfológica do agente etiológico da pinta preta em solanáceas no Brasil.
Este trabalho objetivou realizar a caracterização molecular e morfológica de isolados de Alternaria obtidos de solanáceas.Resumo 504_1
Leachate treatment process at a municipal stabilized landfill by catalytic ozonation: an exploratory study from Taguchi orthogonal array
Catalytic ozonation has been recognized in the scientific community as an efficient technique, reaching elevated rates of recalcitrant organic material mineralization, even at the presence of scavenger species of hydroxyl free radicals. This study presents the most significant factors involving the leachate treatment stabilized by the municipal landfill of the city of Guaratinguetá, State of São Paulo, Brazil, by using a catalytic ozonation activated by metallic ions Fe3+, Zn2+, Mn2+, Ni2+ and Cr3+. The Taguchi L16 orthogonal array and its associated statistical methods were also used in this study. Among the researched ions, the most notable catalysis was obtained with ferric ion, statistically significant in the reduction of COD with a confidence level of 99.5%.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES
Microbially charged redox flow battery: coupling a bioelectrochemical cell with a redox flow battery
ISMET 6 - General Meeting of the International Society for Microbial Electrochemistry and TechnologyRedox flow batteries (RFB) are electrochemical systems applied in the conversion and storage of
chemical energy in electricity. Red ox chemical species (in soluble form) are the main responsible for the
energy storage. Quinones are electroactive molecules applied in RFB because of their chemical and
physical properties.
The aim of this work is to develop an innovative technology to generate and storage the energy
resultant from Bioelectrochemical system (BES). The strategy outlined was coupling a BES with a RFB
that present potential to combine bioenergy production and storage in a microbially charged redox flow
battery.
Firstly, a BES system was studied with Geobacter su/furreducens as biocatalyst to convert a quinone
(2,6-anthraquinone) in its respective reduced form, acetate being the carbon source used. The BES
presented current intensities around 500 mA.m·2 and power densities around 2 wm·
2. The reduction
was assessed visually by a typical colour change (from yellow to dark red) and by cyclic voltammetry.
Simultaneously, as a control, the 2,6-anthraquinone was electrochemically reduced applying and
controlling the cathode potential where the reduction was also observed by colour change and by cyclic
voltammetry.
In an RFB, the quinone bioreduced in tlie BES and electrochemically reduced in the electrochemical cell
were studied using potassium hexacyanoferrate as the second redox chemical species for
discharging/charging cycles in the RFB as the proof of concept of the microbially charged redox flow
battery. The study was performed in a 25 cm2 single red ox flow cell (RF) with a constant current density
of 0.2 mA.cm2 where coulombic efficiency, voltage efficiency and energy efficiency were observed for
10 cycles.info:eu-repo/semantics/publishedVersio
Modelling the Recoherence of Mesoscopic Superpositions in Dissipative Environments
A model is presented to describe the recently proposed experiment (J.
Raimond,
M. Brune and S. Haroche Phys. Rev. Lett {\bf 79}, 1964 (1997)) where a
mesoscopic superposition of radiation states is prepared in a high-Q cavity
which is coupled to a similar resonator. The dynamical coherence loss of such
state in the absence of dissipation is reversible and can in principle be
observed. We show how this picture is modified due to the presence of the
environmental couplings. Analytical expressions for the experimental
conditional probabilities and the linear entropy are given. We conclude that
the phenomenon can still be observed provided the ratio between the damping
constant and the inter-cavities coupling does not exceed about a few percent.
This observation is favored for superpositions of states with large overlap.Comment: 13 pages, 6 figure
Coupling a bioelectrochemical cell with a redox flow battery for sustainable energy production and storage
Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Bioelectrochemical systems (BES) are devices capable to convert chemical energy into electricity through the degradation of different organic compounds using electroactive bacteria as biocatalyst. The ability of microorganisms to form biofilms in electrode surfaces allows the transport of electrons, resultant from the oxidation of carbon sources, to an terminal electron acceptor [1]. Redox flow batteries (RFB) are electrochemical systems applied in the conversion and storage of chemical energy in electricity. Redox chemical species (in soluble form) are the main responsible for the energy storage [2]. Quinones are electroactive molecules applied in RFB because of their chemical and physical properties. The aim of this work is to develop an innovative technology to generate and storage the energy resultant from BES. The strategy outlined is coupling a BES with a RFB that present potential to combine bioenergy production and storage in a microbially charged redox flow battery. [...]info:eu-repo/semantics/publishedVersio
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