title: Thermal characterization in vitro of human nail: photoacoustic study of the aging process.
abstract: In the present work, the rear photoacoustic signal technique is used to determine thermal properties of human nails. The aging process of the human nail is analyzed through its thermal diffusivity and specific heat and using these results, thermal conductivity and thermal effusivity is determined. The study in vitro of this natural polymer showed a minimum for thermal properties to age about 20 years and an increase and possible saturation of them for ages over 50 years. The minimum value found for thermal diffusivity was close to 10x10(-4) cm2 s(-1) with saturation near 18x10(-4) cm2 s(-1). Thermal conductivity and effusivity presents the same behavior.
authors: Departamento de Física, Universidade Estadual de Maringá, Maringá, PR, Brazil. daniele@ufba.br
authors: Daniele Toniolo
authors: DT
authors: Dias
authors: Alysson
authors: A
authors: Steimacher
authors: Antonio Carlos
authors: AC
authors: Bento
authors: Antonio Medina
authors: AM
authors: Neto
authors: Mauro Luciano
authors: ML
authors: Baesso
mesh_terms: D000162:Acoustics; D000375:Aging; D006801:Humans; D009262:Nails / Q000737:chemistry*; D010777:Photochemistry