On the dynamics of bubbles in boiling water

We investigate the dynamics of many interacting bubbles in boiling water by using a laser scattering experiment. Specifically, we analyze the temporal variations of a laser intensity signal which passed through a sample of boiling water. Our empirical results indicate that the return interval distribution of the laser signal does not follow an exponential distribution; contrariwise, a heavy-tailed distribution has been found. Additionally, we compare the experimental results with those obtained from a minimalist phenomenological model, finding a good agreement.Comment: Accepted for publication in Chaos, Solitons & Fractal

Near-IR emission in Pr(3+)single doped and tunable near-IR emission in Pr3+/Yb3+ codoped tellurite tungstate glasses for broadband optical amplifiers

CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPA study of the broadband near-infrared emission in Pr3+ single doped and Pr3+/Yb3+ codoped tellurite-tungstate glasses for optical amplification is presented. In the Pr3+ single doped samples pumped at 474 nm the emission band at 1480 nm presents a FWHM of similar to 140 nm. The Yb3+ addition produces a FWHM broadening up to 155 nm, achieved through the (1)G(4)-H-3(5) transition. The emission spectra when the codoped sample is pumped at 980 nm shows efficient energy transfer from Yb3+ to Pr3+ resulting in an intense Pr3+ emission around 1330 nm. This shows that changing the pump wavelength it is possible to select the D-1(2)-(1)G(4) or the (1)G(4)-H-3(5) transition, displacing the emission band from similar to 1480 to similar to 1330 nm. (C) 2014 Elsevier B.V. All rights reserved.A study of the broadband near-infrared emission in Pr3+ single doped and Pr3+/Yb3+ codoped tellurite-tungstate glasses for optical amplification is presented. In the Pr3+ single doped samples pumped at 474 nm the emission band at 1480 nm presents a FWHM of similar to 140 nm. The Yb3+ addition produces a FWHM broadening up to 155 nm, achieved through the (1)G(4)-H-3(5) transition. The emission spectra when the codoped sample is pumped at 980 nm shows efficient energy transfer from Yb3+ to Pr3+ resulting in an intense Pr3+ emission around 1330 nm. This shows that changing the pump wavelength it is possible to select the D-1(2)-(1)G(4) or the (1)G(4)-H-3(5) transition, displacing the emission band from similar to 1480 to similar to 1330 nm.36610201026CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPCNPq [574017/2008]FAPESP [2005/51689-2, 2008/57857-2, 2012/04291-7, 2009/54066-7]574017/20082005/51689-2; 2008/ 57857-2; 2009/54066-7; 2012/04291-7The Authors would like to thank CNPq (INCT/FOTONICOM, grant 574017/2008) and FAPESP (grants 2005/51689-2, 2008/57857-2 and 2012/04291-7) for their financial support; to the "Laboratorio multiusuario de espectroscopia optica avancada" (LMEOA) for the loan of the spectrofluorimeter (FAPESP grant 2009/54066-7); to professor Antonio Medina Neto and Dr. Leandro Herculano for help in some lifetime measurements performed at "Universidade Estadual de Maringa"; and to the professor Hugo Fragnito for the helpful discussions