The Influence of Ethanol Extraction in the High Temperature Steaming Induced Discoloration Process of Locust (Robinia pseudoacacia) Wood

2012 ◽  
Vol 538-541 ◽  
pp. 2194-2198
Author(s):  
Peng Zhang ◽  
Yong Ming Fan ◽  
Jian Min Gao
Keyword(s):  
Heat Treatment ◽  
Absorption Spectrum ◽  
Aromatic Ring ◽  
Infrared Absorption ◽  
Infrared Absorption Spectrum ◽  
Robinia Pseudoacacia ◽  
Treated Wood ◽  
Decomposition Reaction ◽  
Ether Bond ◽  
Heat Treated

The purpose of the experiment is to get more ideal color and raise the value of Locust wood after heat treatment. We chose ethanol as the solvent and heated locust wood in vapor environment at 120°C for 24 hours. Compare the infrared absorption spectrum of heat treated powder and heat treated powder after extracted. It turned out that: (1) extraction could wipe out the great mass of substance with ethenyl(C=C), ether bond(C-O-C), hydroxy (-OH) and aromatic ring; (2) The synthetic reaction and decomposition reaction of ethenyl(C=C), ether bond(C-O-C), hydroxy (-OH) and aromatic ring would lead to decrease of b* and rise of a*, but have no impact on L*;(3) Heat treatment would reduce the number of aromatic nucleus. Hydroxyl would be oxidized to carbonyl group. Instauration organic esters produced. Heat treated wood after extracted wouldn’t occur these reaction. Powder’s infrared absorption spectrum also shows that functional group in aromatic ring has decreased after extraction and heat treated.

Hydrogen Bonding and Microvoid Stability in a-Si:H

1994 ◽  
Vol 336 ◽  
Author(s):  
M. J. Van Den Boogaard ◽  
A. C. Van Der Steege ◽  
W. G. J. H. M. Van Sark ◽  
W. F. Van Der Weg
Keyword(s):  
Heat Treatment ◽  
Hydrogen Bonding ◽  
Absorption Spectrum ◽  
Infrared Absorption ◽  
Atomic Hydrogen ◽  
Infrared Absorption Spectrum ◽  
Internal Surfaces ◽  
Initial Stage

ABSTRACTWe have annealed PECVD a-Si:H films at 250, 300, and 350°C and measured the evolution of the infrared absorption spectrum. We observe that, during the initial stage of such a heat treatment, atomic hydrogen migrates from the isolated state to the clustered state. Thus diffusion of atomic hydrogen must occur around 300°C. Microvoids with internal surfaces covered with SiH bonds appear to be more stable than voids lined with SiH2 bonds and (SiH2)n polymers.

Infrared absorption spectrum of vanadyl pentaammoniate

1971 ◽  
Vol 15 (4) ◽  
pp. 1349-1351
Author(s):  
L. V. Kobets ◽  
N. I. Vorob'ev ◽  
V. V. Pechkovskii ◽  
A. I. Komyak
Keyword(s):  
Absorption Spectrum ◽  
Infrared Absorption ◽  
Infrared Absorption Spectrum

The infrared absorption spectrum of 18O-labelled nitrobenzene

1964 ◽  
Vol 20 (2) ◽  
pp. 179-185 ◽  
Author(s):  
S. Pinchas ◽  
D. Samuel ◽  
B.L. Silver
Keyword(s):  
Absorption Spectrum ◽  
Infrared Absorption ◽  
Infrared Absorption Spectrum

Comparison of the color and weight change in Paulownia tomentosa and Pinus koraiensis wood heat-treated in hot oil and hot air

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 5574-5585
Author(s):  
Intan Fajar Suri ◽  
Jong Ho Kim ◽  
Byantara Darsan Purusatama ◽  
Go Un Yang ◽  
Denni Prasetia ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Color Change ◽  
Treated Wood ◽  
Pinus Koraiensis ◽  
Weight Changes ◽  
Paulownia Tomentosa ◽  
Wood Color ◽  
Color Changes ◽  
Hot Air ◽  
Heat Treated

Color changes were tested and compared for heat-treated Paulownia tomentosa and Pinus koraiensis wood treated with hot oil or hot air for further utilization of these species. Hot oil and hot air treatments were conducted at 180, 200, and 220 °C for 1, 2, and 3 h. Heat-treated wood color changes were determined using the CIE-Lab color system. Weight changes of the wood before and after heat treatment were also determined. The weight of the oil heat-treated wood increased considerably but it decreased in air heat-treated wood. The oil heat-treated samples showed a greater decrease in lightness (L*) than air heat-treated samples. A significant change in L* was observed in Paulownia tomentosa. The red/green chromaticity (a*) of both wood samples increased at 180 and 200 °C and slightly decreased at 220 °C. The yellow/blue chromaticity (b*) in both wood samples increased at 180 °C, but it rapidly decreased with increasing treatment durations at 200 and 220 °C. The overall color change (ΔE*) in both heat treatments increased with increasing temperature, being higher in Paulownia tomentosa than in Pinus koraiensis. In conclusion, oil heat treatment reduced treatment duration and was a more effective method than air heat treatment in improving wood color.

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