SciELO - Scientific Electronic Library Online

 
vol.6 número1SIMULACIÓN DEL SECADO CONVENCIONAL DE LA MADERAINFLUENCIA DE LA ESTRUCTURA ANATÓMICA EN LA PERMEABILIDAD ESPECIFICA TRANSVERSAL AL GAS DEL PINO RADIATA índice de autoresíndice de materiabúsqueda de artículos
Home Pagelista alfabética de revistas  

Servicios Personalizados

Revista

Articulo

Indicadores

Links relacionados

Compartir


Maderas. Ciencia y tecnología

versión On-line ISSN 0718-221X

Resumen

NIJDAM, J.J; LEHMANN, E  y  KEEY, R.B. APPLICATION OF NEUTRON RADIOGRAPHY TO INVESTIGATE CHANGES IN PERMEABILITY IN BACTERIA TREATED PINUS RADIATA TIMBER. Maderas, Cienc. tecnol. [online]. 2004, vol.6, n.1, pp.19-31. ISSN 0718-221X.  http://dx.doi.org/10.4067/S0718-221X2004000100002.

The permeability of softwoods can be enhanced by selective bacterial attack of the pit membranes. In this paper, green flat-sawn Pinus radiata sapwood boards were sprinkled for various exposure times with a nutrient solution containing a mixed bacterial population. The timber samples were subsequently dried and the tangential absorption of water was measured using neutron radiography to track the movement of moisture within the wood. There was a significant increase in water absorption after only two days of bacterial exposure, and the quantity of water absorption nearly doubled after a fortnight of bacterial exposure. These measurements showed that dried timber that has had a greater extent of bacterial exposure in the green condition has more void space available to store and conduct water. Scanning electron micrographs showed that bacteria had colonised the pits near the surface of the wood after only two days bacterial exposure. There was also clear evidence of damage to the margo-fibrils and tori of the pit membranes, which was attributed to enzymatic degradation by the bacteria. This study confirms the conclusions drawn by other investigators that bacteria degrade the pits in the green sapwood, so that many of the pathways for moisture flow remain unblocked once the wood is dried

Palabras clave : bordered pit; pit aspiration; wood; lumber.

        · texto en Inglés

 

Creative Commons License Todo el contenido de esta revista, excepto dónde está identificado, está bajo una Licencia Creative Commons