Proceedings e report - Firenze University Press

elative L* reduction [%]
60
40
20
0
10 -1
WOOD SCIENCE FOR CONSERVATION OF CULTURAL HERITAGE
10 10 3
Aging time [h]
61
ΔE
40
20
0
10 -1
10 10 3
Aging time [h]
Fig. 3: Time-temperature superposition of the color data from Fig. 2 at a reference temperature of 180 o C
( :90 o C, :120 o C, :150 o C, :180 o C, :naturally aging).
ln(aT)
16
12
8
4
0
Temp.[ o C] a T
180 1
150 13
120 190
90 2260
Naturally
1370000
aging
R 2 =0.994
E a=1.17×10 5 J/mol
0.002 0.003 0.004
1/T [K -1 ]
Temp.[ o C] a T
180 1
150 13
120 181
90 1860
Naturally
aging
1370000
Fig. 4: Arrhenius plot of ln(aT) as a function of 1/T
calculated from L*. (○: shift factor of accelerated
aged data, ●: shift factor of naturally aging data,
──:regression line to shift factors of accelerated aged
data, Ea: apparent activation energy obtained from
slope of regression line)
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