Departamento de Física e Química
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Recent Submissions
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Hamiltonian analysis and positivity of a new massive spin-2 model
(Classical and Quantum Gravity, 2022) [Artigo]Recently a new model has been proposed to describe free massive spin-2 particles in D dimensions in terms of a non symmetric rank-2 tensor e μν and a mixed symmetry tensor B μ[αβ]. The model is invariant under linearized ... -
Higher spin analogs of linearized topologically massive gravity and linearized new massive gravity
(Physical Review D, 2021) [Artigo]We suggest a new spin-4 self-dual model (parity singlet) and a new spin-4 parity doublet in D=2+1. They are of higher order in derivatives and are described by a totally symmetric rank-4 tensor without extra auxiliary ... -
Plasma polymer deposition of neutral agent carvacrol on a metallic surface by using dielectric barrier discharge plasma in ambient air
(Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST, 2020) [Trabalho apresentado em evento]This experiment was conducted by newly designed home-made planar type DBD plasma generator in ambient, with industrial argon as the primary plasma-forming and a carrier gas of monomer. Natural agent Carvacrol monomer was ... -
Development of platinum-niobium as a CO tolerant catalyst for PEFC operating with CO contaminated hydrogen
(ECS Transactions, 2015) [Trabalho apresentado em evento]This paper presents the results of a bimetallic Pt3Nb/C catalyst prepared by thermal treatment in dilute reductive atmosphere (5% H2 in Ar) to obtain a CO-tolerant catalyst. The thermal treatment leads to the formation of ... -
Can mechanical agitation induce stable physicochemical changes on a solvent?
(International Journal of High Dilution Research, 2013) [Artigo]Why do serial agitations are so important to prepare a homeopathic medicine? This question has been discussed for two centuries but it still remains opened. Accordingly some experimental evidences, agitated (and diluted) ... -
Um esboço da história do conceito de trabalho virtual e suas aplicações
(Revista Brasileira de Ensino de Fisica, 2008) [Artigo]In this work is discussed the question concerning the origin and development of the principle of virtual work as a fundamental principle in the study of the analytical mechanics, and particularly of the static equilibrium ... -
Perturbative bosonization from two-point correlation functions
(Physical Review D - Particles, Fields, Gravitation and Cosmology, 2003) [Artigo]Here we address the problem of bosonizing massive fermions without making expansions in the fermion masses in both massive [Formula Presented] and [Formula Presented] with N fermion flavors including also a Thirring coupling. ... -
A transition from a decelerated to an accelerated phase of the universe expansion from the simplest non-trivial polynomial function of T in the f(R, T) formalism
(Astrophysics and Space Science, 2016) [Artigo]In this work we present cosmological solutions from the simplest non-trivial polynomial function of T in f(R, T) theory of gravity, with R and T standing for the Ricci scalar and trace of the energy-momentum tensor, ... -
Plasma deposition of amorphous carbon films from CH4 atmospheres highly diluted in Ar
(Thin Solid Films, 2002) [Artigo]The deposition, structure and mechanical properties of hydrogenated amorphous carbon films grown in highly Ar-diluted CH4 atmospheres were investigated for a total pressure of 13 Pa. Films were investigated as a function ... -
An investigation of multiple jet acetylene flames
(International Communications in Heat and Mass Transfer, 1996) [Artigo]The interaction between turbulent acetylene flames was investigated experimentally by the analysis of their visible lengths. The study involved 1, 2, 3 and 5 turbulent flames formed by parallel vertical jets whose relative ... -
Heat-kernel expansion at finite temperature
(Physical Review D, 1992) [Artigo]We show how the zero-temperature result for the heat-kernel asymptotic expansion can be generalized to the finite-temperature one. We observe that this general result depends on the interesting ratio, where is the ... -
Can dark matter–dark energy interaction alleviate the cosmic coincidence problem?
(European Physical Journal C, 2022) [Artigo]In this paper we study a model of interacting dark energy–dark matter where the ratio between these components is not constant, changing from early to late times in such a way that the model can solve or alleviate the ... -
Understanding the acid dissolution of Serpentinites (Tailings and waste rock) for use in indirect mineral carbonation
(South African Journal of Chemical Engineering, 2022) [Artigo]Solid carbonates can be formed by indirect mineral carbonation using the pH swing method for CO2 storage. It occurs at low temperatures and pressures in four stages: acid dissolution, purification, carbonation, and recovery. ... -
Comprehensive approach of methods for microstructural analysis and analytical tools in lignocellulosic biomass assessment – A review
(Bioresource Technology, 2022) [Resenha]The trend in the modern world is to replace fossil fuels with green energy sources in order to reduce their environmental impact. The biorefinery industry, within this premise, needs to establish quantitative and qualitative ... -
Higher order derivatives extension of Maxwell-Chern-Simons electrodynamics in the presence of field sources and material boundaries
(Physical Review D, 2022) [Artigo]In this paper we consider some new classical effects obtained for a planar electrodynamics with the presence of a higher order derivatives term. The model can be interpreted as a kind of extension for the 3d Maxwell-Chern-Simons ... -
A test of the standard dark matter density evolution law using galaxy clusters and cosmic chronometers
(European Physical Journal C, 2022) [Artigo]In this paper, we implement a test of the standard law for the dark matter density evolution as a function of redshift. For this purpose, only a flat universe and the validity of the FRW metric are assumed. A deformed dark ... -
A search for the variation of speed of light using galaxy cluster gas mass fraction measurements
(Journal of Cosmology and Astroparticle Physics, 2021) [Artigo]In this paper, we implement a new method to test the invariance of the speed of light (c) as a function of redshift, by combining the measurements of galaxy cluster gas mass fraction, H(z) from cosmic chronometers, and ... -
Self-dual models in D=2+1 from dimensional reduction
(Annals of Physics, 2021) [Artigo]Here we perform a Kaluza–Klein dimensional reduction of Vasiliev's first-order description of massless spin-s particles from D=3+1 to D=2+1 and derive first-order self-dual models describing particles with helicities ±s ... -
Exploring environmental, economic and social aspects of rainwater harvesting systems: A review
(Sustainable Cities and Society, 2022) [Artigo]Rainwater harvesting systems (RWHS) can significantly contribute to the sustainability of cities and rural areas. In addition to their more obvious benefits (such as the ability to supply water in a decentralized manner, ... -
Effect of cold atmospheric plasma jet associated to polyene antifungals on candida albicans biofilms
(Molecules, 2021) [Artigo]The increasing incidence of antifungal resistance represents a great challenge in the medical area and, for this reason, new therapeutic alternatives for the treatment of fungal infections are urgently required. Cold ...