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  • 1
    Electronic Resource
    Electronic Resource
    Use of trioxane for improvement of hygroscopic and acoustic properties of wood for musical instruments (1993)
    Springer
    Wood science and technology 27 (1993), S. 151-160 
    Details
    ISSN: 1432-5225
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Summary As a reagent source for the formalization of wood, trioxane was used instead of conventional paraformaldehyde. From preliminary experiments it became apparent that trioxane depolymerizes to formaldehyde by heating in the presence of some metallic salts. Formalization of wood with trioxane was carried out under the catalysis of sulfur dioxide (SO2) along with these salts. The hygroscopic and acoustic properties were considerably improved by the treatment. Especially when the reaction was catalyzed by a combination of SO2 and Fe2(SO4)3, the antiswelling efficiency (ASE) reached nearly 70%, the specific dynamic Young's modulus (E/ϱ) in the radial direction increased about 20%, and the loss tangent (tan δ) decreased about 30% and 50% in the longitudinal and radial directions, respectively. In this case, the modulus of rupture did not appreciably decrease in the radial direction. This is comparable to the most prominent results obtained so far by SO2 catalyzed formalization with tetraoxane. It can be concluded that trioxane is very effective as a reagent source for formalization. The increase in acoustic converting efficiency, $$\sqrt {(E/\varrho ^3 )} /\tan$$ δ, of about twofold in the radial direction and decrease in hygroscopicity of more than 60% should not only enrich the sound volume of musical instruments but also stabilize their tone quality against humidity changes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206232
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  • 2
    Electronic Resource
    Electronic Resource
    Chemical modification of wood by non-formaldehyde cross-linking reagents (1994)
    Springer
    Wood science and technology 28 (1994), S. 101-110 
    Details
    ISSN: 1432-5225
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Summary Using sulfur dioxide (SO2) as catalyst, wood specimens were treated with nonformaldehyde cross-linking reagents such as glyoxal, glutaraldehyde and dimethylol dihydroxy ethyleneurea (DMDHEU). The results of dimensional stability, acoustic properties, and mechanical strength tests were compared with those obtained from formaldehyde treatment. With glyoxal and glutaraldehyde treatments, antiswelling efficiency (ASE) reached around 70%, which is comparable to the values attained by formaldehyde treatment, although the accompanying weight gain was much larger than for the latter, whereas DMDHEU did not give sufficiently high ASE. None of the treatments, significantly increased specific dynamic Young's modulus (E/ρ) with the exception of the DMDHEU treatment, loss tangent (tan δ) decreased substantially, about 50 and 60% in longitudinal and radial directions respectively, which were somewhat exceeding the formaldehyde treatment. The results suggested that the improvement of the dimensional stability and acoustic properties is partly attributed to the formation of cross-links.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00192689
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  • 3
    Electronic Resource
    Electronic Resource
    Chemical modification of wood by non-formaldehyde cross-linking reagents (1995)
    Springer
    Wood science and technology 29 (1995), S. 243-251 
    Details
    ISSN: 1432-5225
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Summary The probability of bond between wood components and glyoxal was examined by means of a mechanical method, infrared (IR) spectrometry, and solid state 13C-nuclear magnetic resonance (NMR) spectrometry. The successive fixation of a compressed wood by the glyoxal treatment suggested the formation of cross-linkings between wood components and/or wood structures. The IR spectra showed that ester bond as well as ether bond was formed between wood components and glyoxal. The existence of linkages between glyoxal and cellulose was indicated also from the NMR spectra. The addition of glycol to the glyoxal solution was investigated from the viewpoint of stabilizing effect of the linkages. When 0.2 mole ratio of glycol was added to 5–10% glyoxal solution, weight gain and antiswelling efficiency (ASE) were largest, however the addition of excessive amount of glycol did not advance further the weight gain and ASE. When an appropriate amount of glycol was added to the impregnation solution, both weight and ASE did not largely reduce even by the repeated hot water soaking. By the treatment without glycol, the dimensional stability after water soaking was attributed to only restraint of the swelling. On the other hand, when the glycol was added, the dimensional stability was developed not only by the restraint of the swelling but also by the buckling effect.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00202084
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  • 4
    Electronic Resource
    Electronic Resource
    Physical and mechanical properties required for violin bow materials II: Comparison of the processing properties and durability between pernambuco and substitutable wood species (1998)
    Springer
    Journal of wood science 44 (1998), S. 142-146 
    Details
    ISSN: 1611-4663
    Keywords: Pernambuco ; Violin bow ; Shearing strength ; Processing property ; Mean microfibril angle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Pernambuco (Guilandina echinata Spreng. syn Caesalpinia echinata Lam.), which has been used for a material of violin bows, was compared with substitutable wood species from the viewpoint of processing properties and durability. The properties required for bow material are discussed. The shearing strength of pernambuco was higher than that of the other wood species at the same specific gravity. High shearing strength seems to be effective for preventing damage to the head (top part) of the bow. The presence of extractives affects the thermal softening of wood material, but ease of handling and permanent retention of form are not particularly superior for pernambuco, although it does have a high extractives content. A peculiarly low loss tangent (tan S) of pernambuco can probably be attributed to the large amount of extractives, rather than the mean microfibril angle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00526260
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  • 5
    Electronic Resource
    Electronic Resource
    Effects of impregnation of simple phenolic and natural polycyclic compounds on physical properties of wood (1999)
    Springer
    Journal of wood science 45 (1999), S. 227-232 
    Details
    ISSN: 1611-4663
    Keywords: Hematoxylin ; Impregnation ; Vibrational property ; Dimensional stability ; Extractive
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The impregnation of various simple phenolic and natural polycyclic compounds into wood was investigated from the viewpoints of vibrational property and dimensional stabilizing effect. When simple phenolic compounds were impregnated, the loss tangent (tan δ) in the longitudinal direction increased linearly with increasing weight gain. Meanwhile, among the natural polycyclic compounds hematoxylin decreased the tan δ drastically by impregnation. It was suggested that the five hydroxyl groups and the pyran ring oxygen in the hematoxylin molecule contribute to formation of the crosslinkage-type hydrogen bonds between wood components. The rigidity of hematoxylin molecules may also be important. By impregnation of about 10% catechol, resorcinol, and saligenin, a 40% level of antiswelling efficiency (ASE) was attained, although a significant dimensional stabilizing effect was not observed after impregnation of natural polycyclic compounds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01177730
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  • 6
    Electronic Resource
    Electronic Resource
    Chemical characteristics of surfaces of hardwood and softwood deteriorated by weathering (1999)
    Springer
    Journal of wood science 45 (1999), S. 348-353 
    Details
    ISSN: 1611-4663
    Keywords: Chemical analysis ; Cryptomeria japonica ; ESR analysis ; IR spectroscopy ; Paraserianthes falcata ; Weathering
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The factors that cause weather-induced deterioration of wood surfaces were determined by chemical and spectroscopic analyses. Albizzia (Paraserianthes falcata Becker.) and sugi (Cryptomeria japonica D. Don) were exposed to two temperate conditions of natural weathering with and without rainfall and to accelerated conditions of artificial weathering coupled with ultraviolet (UV) light irradiation and water flashing. Infrared spectroscopic analysis showed that the oxidative reaction of lignin was observed under all conditions of weathering for both wood species. However, a marked decrease in lignin and hemicellulose content were recognized when albizzia woods were exposed to weathering with water. Lignin content in the softwood sugi did not decrease as much as in albizzia even in the presence of water, but the modification of lignin macromolecules was assumed to be accelerated by water, as seen by electron spin resonance spectroscopy. These results showed that the presence of water promotes the weathering deterioration of wood under UV irradiation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00833502
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  • 7
    Electronic Resource
    Electronic Resource
    Vibrational property changes of spruce wood by impregnation with water-soluble extractives of pernambuco (Guilandina echinata Spreng.) (1999)
    Springer
    Journal of wood science 45 (1999), S. 470-474 
    Details
    ISSN: 1611-4663
    Keywords: Pernambuco ; Vibrational property ; Extractives ; Impregnation ; Musical instrument
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Sitka spruce (Picea sitchensis Carr.) was treated with water-soluble extractive components of pernambuco (Guilandina echinata Spreng. syn Caesalpinia echinata Lam.) by two methods: impregnation under evacuation using an aspirator and repetitive surface application using a brush. The influence of these treatments on the vibrational properties were examined. The loss tangent (tan δ) of the impregnated specimen decreased, up to nearly a half of its original value, with increasing weight gain. It is suggested that the decrease in tan δ results from impregnation of the extractive components into the amorphous region of cell walls, forming secondary bonds between matrix substances. The surface application of the extractive components, on the other hand, hardly brought about the desirable change in vibrational properties.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00538955
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  • 8
    Electronic Resource
    Electronic Resource
    Working mechanism of adsorbed water on the vibrational properties of wood impregnated with extractives of pernambuco (Guilandina echinata Spreng.) (2000)
    Springer
    Journal of wood science 46 (2000), S. 122-129 
    Details
    ISSN: 1611-4663
    Keywords: Pernambuco ; Extractives ; Adsorbed water Vibrational property ; Loss tangent
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract To clarify the lowering mechanism of loss tangen (tanδ) of sitka spruce (Picea sitchensis Carr.) wood impregnated with extractives of pernambuco (Guilandina echinata Spreng. synCaesalpinia echinata Lam.), we examined the vibrational properties of the impregnated wood in relation to the adsorbed water. The results obtained were as follows: (1) The equilibrium moisture content (EMC) of impregnated sitka spruce decreased to some extent compared with untreated wood. (2) Frequency dependencies of tanδ a about 400–8000Hz showed that impregnated wood has much lower tan δ than untreated wood at around 9% mois ture content (MC), except for the high-frequency region. At high relative humidity, impregnated wood has a minimum tanδ (at around 4000Hz); and at other frequency ranges the tanδ of impregnated wood did not differ considerably from that of untreated wood. (3) The apparent activation energy of the mechanical relaxation process (ΔE) concerned with adsorbed water molecules was higher for impregnated specimens than for untreated ones at moderately high relative humidity, whereas at high relative humidity the difference was not observed. Based on these results, it is thought that the tanδ of impregnated wood decreased at low rela tive humidity because of the formation of direct hydrogen bonds between impregnated extractives and wood components. However, when the specimen is at higher relative
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00777358
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  • 9
    Electronic Resource
    Electronic Resource
    Vibrational property changes of spruce wood by impregnation with watersoluble extractives of pernambuco (Guilandina echinata Spreng.) II: structural analysis of extractive components (2000)
    Springer
    Journal of wood science 46 (2000), S. 253-257 
    Details
    ISSN: 1611-4663
    Keywords: Pernambuco ; Extractives ; Protosappanin B ; Brazilin ; Vibrational property
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Heartwood of pernambuco (Guilandina echinata Spreng, synCaesalpinia echinata Lam.), which has been used as material for violin bows, was extracted by soaking in water, and the obtained extractives were analyzed. The main components of the extractives were identified to be protosappanin B and brazilin. In particular, protosappanin B occupied about 40% of the pernambuco extractives. The loss tangent (tanδ) of spruce wood impregnated with protosappanin B decreased markedly, the same as that of specimens impregnated with extractives before being purified. It is expected that protosappanin B can make a contribution to the decrease in tanδ due to impregnation with extractives.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00776458
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  • 10
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    Physico-chemical indicators of inter-specific variability in vibration damping of wood (2010)
    Springer
    Details
    Publication Date: 2010-01-01
    Print ISSN: 1286-4560
    Electronic ISSN: 1297-966X
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Springer
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