Application of X-Ray Technique in Nondestructive Evaluation of Eucalypt Wood

Abstract

X-rays were initially used for the inspection of special-purpose wood pieces for quantitative evaluation of wood properties of different species. X-ray densitometry has had its use expanded in dendroclimatology of Picea engelmannii trees. Subsequent laboratories developed applications of X-ray densitometry for environmental, wood science and technology, and related areas. This paper describes the basic methodology of X-ray densitometry applied to the eucalypt wood analysis, as well as presenting the results of applications in three areas: (i) evaluation of wood biodegradation by white rot fungi, (ii) detection of sapwood and heartwood, and (iii) determination of the effect of management on wood properties. The wood decayed by white rot fungi was detected by X-ray densitometry with a decreasing wood density due to the biodegradation of cell wall components. The sapwood and heartwood of eucalypts were separated in response to the attenuation of X-rays, refl ected by the wood anatomical structure and chemical composition. Also, in eucalypt trees after the application of irrigation and fertilizationirrigation characteristic wood density profi les were detected. In addition, the signifi cant potential of X-ray densitometry for eucalypt wood research and analysis is discussed.

RELATIONSHIP BETWEEN CLIMATE VARIABLES, TRUNK GROWTH RATE AND WOOD DENSITY OF Eucalyptus grandis W. Mill ex Maiden TREES

“…Therefore, variation pattern of the wood density of 48-month old Eucalyptus trees, is characterized by the presence of juvenile wood and early transition. The pity density value may be a consequence of the occurrence of crystals and starch in the parenchyma cells (TOMAZELLO FILHO, 2006;TOMAZELLO FILHO et al, 2008;SETTE JR et al, 2012) in the wood of E. grandis trees, in addition to wood density fluctuations in the profiles due to the variations in vase diameter/frequency and the occurrence of thicker wall fiber bands.…”

Propriedades físico-mecânicas do lenho deteriorado por fungos apodrecedores de árvores de Tipuana tipu

“…Após climatização, foram dispostas e radiografadas sobre filmes de raios X em equipamento Hewlett Packard, Faxitron 43805 N. As radiografias do lenho foram reveladas e obtidas imagens digitais em scanner com resolução de 1000 dpi e analisadas nos programas CRAD e CERD (AMARAL; TOMAZELLO-FILHO, 1998;TOMAZELLO-FILHO et al, 2008). Para cada amostra, foi determinado o respectivo perfil radial de densidade aparente do lenho (base massa/volume a 10%), possibilitando caracterizar as regiões sadias e afetadas por fungos xilófagos e demarcar e cortar os corpos de prova para a determinação do módulo de ruptura e módulo de elasticidade à flexão estática.…”

“…Neste sentido, Macchioni et al (2007) e Tomazello-Filho et al (2008) sugeriram, também, a aplicação dessa técnica na avaliação expedita da durabilidade natural do lenho em ensaios laboratoriais e de campo.…”

“…No estágio incipiente de biodeterioração do lenho de tipuana, observou-se que a discreta alteração macroscópica de coloração resulta em uma significativa perda de 55% do módulo de ruptura, atingindo 79-93% em estágio avançado do apodrecimento do lenho. Essa relação entre biodeterioração e redução significativa da tensão de ruptura mecânica foi observada no lenho de ash (Fraxinus excelsior) nos estágios iniciais de biodeterioração pelo fungo de podridão branca Inonotus hispidus (YOUNG, 1984) e de outras espécies de folhosas afetados por diversos fungos xilófagos (BODIG;JAYNE, 1992;EATON;HALE, 1993;TANAKA, 1991;TOMAZELLO-FILHO et al, 2008).…”

La micro-tomographie RX, un outil pour une analyse anatomique fine du bois

“…Even in wood science, its possibilities are employed. In its two dimensional form, X-ray analysis is already used for densitometry (Knapic et al, 2007;Macchioni et al, 2007;Tomazello et al, 2008). X-ray computed tomography in three dimensions is utilized for the analysis of low-density fibreboard under compression (Badel et al, 2008), study of wood-plastic composites (Wang et al, 2007), detection of organosilicon compounds (De Vetter et al, 2006), microstructure analysis of spruce wood (Trtik et al, 2007) and quantitative wood anatomy (Steppe et al, 2004).…”