Maderas:Ciencia y Tecnología 2(2):2000.
Copyright © 2003, CAB International
ET- Automation of production for the wood industry.
FT- Automatizacion de la produccion para las industrias de la madera.
AU- Charpentier, P.;Ramos, M.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 225-231
AB- The paper starts with a brief general presentation on the
characteristics of manufacturing enterprises in the industrial wood
sector. Three parts follow that discuss the introduction of
automation to the industry. These cover (1) the function of
'capture', which permits the characterization of the wood product,
(2) the organization and development of flow in the enterprise, and
(3) the monitoring of production.
ET- System of reverse engineering for the design of furniture by means of
the use of a portable coordinate measuring machine.
FT- Sistema de Ingenieria de Reversa para el diseno de muebles mediante
la utilizacion de una maquina de medicion de coordenadas portatil.
AU- Moraga, R.;Baesler, F.;Harrison, O.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 218-224
RE- 12 ref.
AB- The first part of the paper discusses the technique of reverse
engineering using portable coordinate measuring machines (CMM), and
the application of the technique to furniture design (with reference
to its potential use in Chile). Finally the results are described of
the practical application of the reverse engineering technique to an
existing bentwood chair using the FAROArm (a CMM).
ET- Heat-hardened and thermoplastic resins: a study of in situ setting in
the manufacture of boards of MDF and laminates.
FT- Resinas termoendurecibles y termoplasticas: estudio del fraguado in-
situ en la fabricacion de tableros mdf y laminados.
AU- Gacitua E., W.;Rials, T. G.;Ballerini A., A.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 207-217
RE- 23 ref.
AB- The first part of the paper discusses the principal processes in the
pressing of wood-based panels and in the setting of adhesives during
heat pressing. Next, a laboratory study is reported of the
manufacture of MDF (medium density fibreboard) and laminated panels
made from fibres of Pinus radiata glued with urea formaldehyde (MDF),
phenol formaldehyde (MDF, laminates) or polyvinyl acetate (MDF,
laminates) resins. Resin curing was monitored in situ using a
dielectric method, and the thermal properties of the resins were
evaluated. The results are presented and analysed in detail.
ET- Populus x euroamericana (Dode) Guinier: sawmilling, drying and
mechanical properties.
FT- Populus x euroamericana (dode) guinier: aserrio, secado y propiedades
mecanicas.
AU- Juacida P., R.;Cuevas D., H.;Saldivar G., E.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 185-195
RE- 25 ref.
AB- Data are reported from a study of 3 clones of Populus euramericana
[Populus canadensis] ('I-72', I-161' and 'I-488') introduced into the
province of Valdivia, Chile in 1976. The 3 clones had similar wood
densities (0.317-0.328 g/m3) and colour, the presence of false
heartwood, splits at the end of logs, and irregular curvatures and
transverse sections. The principal difference between the clones is
in diameter and crown height. Clone 'I-488' was the best in terms of
sawnwood production and quality. All 3 clones had wood of a very low
mechanical resistance.
ET- Conventional drying of alamo (Populus nigra).
FT- Secado convencional de la especie alamo (Populus nigra).
AU- Sanchez A., R.;Ruiz T., P.;Ramirez R., J.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 177-184
RE- 7 ref.
AB- A laboratory-scale drying test was carried out using sawnwood of
(Populus nigra), which was dried from green to 10% humidity under 38
mm pressure. Three trials were done using loads with pieces of the
same size (38 x 110 x 900 mm) and number but with slightly different
initial basic densities (300, 308 and 325 kg/m2) and humidity
contents (170, 143 and 143%). A different drying schedule was used
for each load; the differences involved the use of different
temperatures, air speeds and time periods at different drying stages
(details are given). For each load measurements were recorded of
humidity gradients and final humidity, and defects were evaluated and
classified. The best results were obtained with the 2 drying
schedules that used air speeds of 3 m/s and minimum temperatures <60
deg in the first stage of drying.
ET- Conventional drying of calden (Prosopis calden) as boards 25 mm
thick.
FT- Secado convencional de la especie calden (Prosopis calden), en tablas
de 25 mm. de espesor.
AU- Gutierrez D., M.;Carmona C., R.;Rallo de la B., M.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 196-206
RE- 6 ref.
AB- Sawnwood of calden (Prosopis calden [Prosopis caldenia]) 25 mm thick,
70-145 mm wide and 0.6-2.0 m long was brought from Argentina to Chile
to study the drying process. Some of the sawnwood was from stems and
some from branches. Details are given of the 3 drying schedules used
(which were designated as mild, moderate and strong) and of the
results obtained from them, in terms of speed of drying, defect
development and gradients of humidity. The drying speed was 10 days
in the most extreme schedule, and 22 and 16 days, respectively, in
the moderate and mild schedules. There were no important defects
resulting from any of the schedules.
ET- Relations between the period of pre-existence of biocontrol agents
and the presence of blue stain in sawnwood of Pinus radiata, under
laboratory conditions.
FT- Relacion entre periodo de preexistencia de biocontroladores y
presencia de mancha azul en madera aserrada de Pinus radiata, en
condiciones de laboratorio.
AU- Garcia, J. M.;Peredo, H. L.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 168-176
RE- 13 ref.
AB- The protective effectiveness of the presence 3 biocontrol agents
(Geotrichum candidum, G. roseum and Trichoderma viride) for various
periods (1, 6 or 11 days) before inoculation with blue stain fungi
(Aspergillus flavus, Aureobasidium pullulans, Ceratocystis pilifera,
Graphium, Penicillium and Sphaeropsis sapinea [Diplodia pinea]), was
tested using 70 x 20 x 7 mm samples of Pinus radiata sapwood prepared
2 days after harvesting. The samples were assessed for blue stain
development 30 days after inoculation with the stain fungus
concerned. The period of pre-existence of the biocontrol agent had a
significant effect on the development of all 6 species of blue stain
only in the case of Geotrichum candidum, which gave increasing
control of stain development the longer it was present before blue
stain inoculation. For the other 2 biocontrol agents (Trichoderma
viride and Geotrichum roseum) the period of pre-existence had very
little effect on the development of any of the stain fungi, which
were either completely or well controlled for all the time periods of
pre-existence concerned.
Record - 14
ET- Determination of the elastic constants of wood for ultrasound. Part
I: modulus of elasticity and modulus of rigidity.
FT- Determinacion de las constantes elasticas de la madera por
ultrasonido parte I: modulos de elasticidad y modulos de rigidez.
AU- Fuentealba, C.;Baradit, E.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 161-167
RE- 17 ref.
AB- The advantages and disadvantages of nondestructive testing for wood
elastic constants using ultrasonic techniques are discussed and the
fundamental theory involved outlined. A practical study is reported
using wood samples from 20-yr-old Pinus radiata from Concepcion,
Chile, in which mechanical and ultrasonic tests were carried out and
the results compared. Twenty samples were obtained from each of 5
trees for testing (1) mechanical compression parallel to the grain
(samples 50 x 50 x 200 mm), (2) mechanical compression perpendicular
to the grain (samples 50 x 50 x 100 mm) and (3) the propagation
velocity of ultrasonic waves (using cubes of dimensions 16, 20, 25,
30 and 50 mm cut in a radial direction). The moduli of elasticity in
longitudinal (L), radial (R) and tangential (T) directions calculated
from the ultrasonic measurements were within similar ranges to those
obtained from the mechanical tests. Results are also reported of the
ultrasonic determination of moduli of rigidity in 6 directions (LT,
TL, RT [no data given], TR, LR, RL) but comparative results from the
mechanical determinations are not provided.
ET- Effect of knots and grain inclination on the propagation velocity and
acoustic impedance of ultrasonic waves in wood of radiata pine.
FT- Efecto de nudos e inclinacion de fibras en la velocidad de
propagacion e impedancia acustica de ondas ultrasonicas en Madera de
pino radiata.
AU- Alejandro M., B. G.;Jose T., K. C.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 150-160
RE- 9 ref.
AB- This study was carried out as part of a project on the utilization of
ultrasonic techniques in the characterization and classification of
wood and its basic composition. The principal objective was to
determine the propagation velocity and acoustic impedance of
ultrasonic waves in defect-free wood of radiata pine [Pinus radiata]
at different grain inclinations (0, 15, 30 and 45 deg ) and densities
(low, medium and high). The results showed that both propagation
velocity and acoustic impedance were affected by wood density and
grain inclination. The effect of wood density on propagation velocity
varied with direction (longitudinal, radial or tangential), while
acoustic impedance increased slightly with density in all 3
directions. The effect of grain inclination on propagation velocity
also varied with direction (parallel or tangential to the grain in
the radial axis, and parallel or radial in the tangential axis), each
showing a decrease with increase in grain inclination. Acoustic
impedance decreased with increasing grain inclination in all
directions.
ET- Radial and longitudinal variation of spiral grain in an adult stand
of maritime pine (Pinus pinaster Ait.).
FT- Variacion radial y en el fuste de la fibra revirada presente en un
rodal adulto de pino maritimo (Pinus pinaster Ait.,).
AU- Rodriguez M., R.;Valenzuela H., L.;Espinosa B., M.
JN- Maderas: Ciencia y Technologia
YR- 2000
VO- 2
NO- 2
PP- 140-149
RE- 13 ref.
AB- Variation in spiral grain was determined in 9 trees (3 in each crown
class - dominant, intermediate and suppressed) in a 44-61-yr-old
unmanaged stand in the Bio-Bio region of Chile. Relationships were
determined between the occurrence of spiral grain and distance from
the pith, cambial age, percentage of summer wood (latewood), ring
width and basic density. Spiral grain was radially distributed
similarly in all the trees, with grain inclination diminishing from
the pith to the cortex. Longitudinally, the inclination of spiral
grain increased with stem height. There was more spiral grain
inclination on the northern aspect, and this situation was more
marked in the crown zone (from 11.3 to 14.4 m). The occurrence of
spiral grain was most related to distance from the pith and cambial
age; there were no statistically significant differences in
occurrence between different crown classes.