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1.
A spectrophotometric assay based on the color reaction between N,N-didecyl-N-methyl-poly(oxyethyl) ammonium propionate (DMPAP) and 4-[4-(dipropylamino) phenylazo]-benzenesulfonic acid (propyl orange)
was used to determine DMPAP concentrations as a wood preservative. The assay was carried out using a propyl orange solution
at pH 2.9. The visible absorption spectrum of propyl orange showed an absorption maximum at 510 nm, which decreased linearly
with increasing DMPAP concentration from 0 to 10 ppm. To apply this assay method to determine DMPAP retention in treated wood,
the influence of wood extractives on the assay was investigated. Extractives from Japanese cedar, hinoki cypress, and Japanese
larch were found to increase apparent DMPAP concentration. However, it was also found that measuring visible absorption at
477 nm prevented overestimation and gave precise values. This assay can be a viable alternative to the current methods for
the determination of DMPAP concentrations. 相似文献
2.
Shin-ichiro Tohmura Atsuko Ishikawa Kohta Miyamoto Akio Inoue 《Journal of Wood Science》2012,58(1):57-63
A mechanism of acetaldehyde emission from wood induced by the addition of ethanol was proposed. It is known that acetaldehyde
generation is due to the oxidation of ethanol via a metabolic process involving alcohol dehydrogenase (ADH) in living bodies.
However, it remains unclear whether the enzymatic alcohol oxidation is applicable to wood. We investigated possible factors
of wood parts, conditioning, storage sites, and heating and sterilization treatments on acetaldehyde emission using the syringe
method and HPLC analysis. We reconfirmed that acetaldehyde emission was observed only when ethanol was added to wood. Greater
acetaldehyde emissions were obtained in heartwood compared to sapwood in both Japanese cedar (Cryptomeria japonica D. Don) and Japanese cypress (Chamaecyparis obtusa Endl.) specimens. In addition, an acetaldehyde conversion rate of 1–2 mol% was determined in green cedar heartwood samples,
while, conversely, air-dried cedar heartwood samples showed 4–5 mol%. Ethylene oxide gas sterilization had the effect of decreasing
acetaldehyde emission on air-dried wood, but not on green wood. Autoclave sterilization could completely prevent acetaldehyde
emissions from both green and air-dried wood. These results suggested that an original ADH in wood and an attached ADH from
the outside via microorganisms onto wood were assumed to be the primary causes of acetaldehyde emissions from wood induced
by the addition of ethanol. 相似文献
3.
Ahmed Mohareb Peter Sirmah Lyne Desharnais Stéphane Dumarçay Mathieu Pétrissans Philippe Gérardin 《Annals of Forest Science》2010,67(5):504-504
4.
J. Nault 《Wood Science and Technology》1988,22(1):73-80
Summary Radial distribution of thujaplicins in western red cedar (Thuja plicata Donn) trees of varying ages was studied in order to assess relative decay resistance of their wood. Samples were extracted with ethanol: benzene (1: 2), and the extractives were analyzed for thujaplicin codtent by a new method utilizing capillary gas chromatography of their methylated derivatives. The combined concentration of thujic acid and methyl thujate was also determined for each sample. Distribution of extractives, thujaplicins and thujic acid, generally increased from pith to outside heartwood, then decreased in the sapwood. Maximum extractive and thujaplicin contents were also related to tree age. This suggests that products made from the wood of younger trees will be less resistant to decay than similar products made from the wood of old trees. 相似文献
5.
The quantities of some extractives in the heartwood of 25 plus tree clones of Japanese cedar (Cryptomeria japonica) from two different sites were investigated to clarify the differences in antitermite properties in relation to clones and
environmental factors. The measured compounds were cubebol, epicubebol, sandaracopimarinol, and ferruginol. The total amounts
of extractives were calculated from gas chromatogram peak areas. The heartwoods from Tano (Tano Forest Research Station, Miyazaki
University; 31° N, 131° E, 130 m asl) tended to contain more of the individual extractives and total extractives than those
from Komenono (Komenono Forest Research Station, Ehime University; 33° N, 132° E, 700 m asl). There was a significant difference
(calculated by analysis of variance) at the 1% level among clones at both sites in quantities of total and individual extractives.
This result suggests that the qualities and quantities of heartwood extractives are largely affected by genetic factors. Spearman’s
rank correlation with the average of the extractive quantities at the sites was investigated. The correlation coefficients
of total extractives, cubebol, epicubebol, sandaracopimarinol, and ferruginol were 0.61, 0.85, 0.76, 0.67, and 0.74, respectively.
This result means that the order of the amounts of these compounds among the cultivars could be maintained at different sites.
It is apparent that both environmental and genetic factors affected the quantities of these extractives in the heartwoods
of Japanese cedar. 相似文献
6.
Heartwood extractives (nonstructural wood components) are believed to be formed from a combination of compounds present in the adjacent sapwood and materials imported from the phloem. The roles of local compounds and imported material in heartwood formation could have important implications for the wood quality of species having naturally durable wood. Stable isotope composition (delta(13)C) was analyzed to assess radial variation in sapwood extractives, and to estimate the relative importance of adjacent sapwood extractives and imported photosynthate in the formation of heartwood extractives. Cellulose and extractives from the outer 39 annual rings of six Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees were isolated and their delta(13)C composition determined. Although the extractives and the cellulose showed different absolute delta(13)C values, the patterns of change over time (as represented by the annual rings) were similar in most cases. Within an annual ring, carbon isotope ratios of extractives were correlated with the cellulose isotope ratio (R2 = 0.33 in sapwood, R2 = 0.34 in heartwood for aqueous acetone-soluble extractives; R2 = 0.41 in sapwood for hot-water-soluble extractives). These data suggest that some sapwood extractives are formed when the wood ring forms, and remain in place until they are converted to heartwood extractives many years later. Sapwood extractives appear to be important sources of materials for the biosynthesis of heartwood extractives in Douglas-fir. 相似文献
7.
Several iron-rich wood samples were investigated using Mössbauer spectroscopy to obtain information on the chemical state of the iron species contained in them. The Mössbauer spectrum of Japanese cedar (Cryptomeria japonica D. Don) wood containing iron species that originated from rusted nails exhibited a symmetrical doublet from a high-spin Fe(III) species, which is expected to be γ-FeOOH (lepidocrocite). Mössbauer absorption attributable to high-spin Fe(III) was observed for ancient buried wood samples of both Japanese cedar and Japanese cypress (Chamaecyparis obtusa Endlicher). Moreover, Mössbauer measurement indicated that the ancient buried Japanese cedar also possessed high-spin Fe(II) species. 相似文献
8.
Ana Lourenço Isabel Baptista Jorge Gominho Helena Pereira 《Journal of Wood Science》2008,54(6):464-469
The pulping wood quality of Acacia melanoxylon was evaluated in relation to the presence of heartwood. The sapwood and heartwood from 20 trees from four sites in Portugal
were evaluated separately at 5% stem height level in terms of chemical composition and kraft pulping aptitude. Heartwood had
more extractives than sapwood ranging from 7.4% to 9.5% and from 4.0% to 4.2%, respectively, and with a heartwood-to-sapwood
ratio for extractives ranging from 1.9 to 2.3. The major component of heartwood extractives was made up of ethanol-soluble
compounds (70% of total extractives). Lignin content was similar in sapwood and heartwood (21.5% and 20.7%, respectively)
as well as the sugar composition. Site did not influence the chemical composition. Pulping heartwood differed from sapwood
in chemical and optical terms: lower values of pulp yield (53% vs 56% respectively), higher kappa number (11 vs. 7), and lower
brightness (28% vs 49%). Acacia melanoxylon wood showed an overall good pulping aptitude, but the presence of heartwood should be taken into account because it decreases
the raw-material quality for pulping. Heartwood content should therefore be considered as a quality variable when using A. melanoxylon wood in pulp industries 相似文献
9.
Yoshio Kijidani Noriko Sakai Keita Kimura Yoshitake Fujisawa Yuichiro Hiraoka Junji Matsumura Shinya Koga 《Journal of Wood Science》2012,58(6):471-478
Hinoki (Chamaecyparis obtusa) wood has been used as a structural material in Japan because of its superior mechanical properties, its excellent durability and the beautiful color of its heartwood. Variations of termite resistance and compositions of extractives among hinoki trees have been reported. However, genetic variation of termite resistance and the effect of heartwood color on termite resistance remain unknown. In this study, we report the characteristics of termite resistance and color indexes (L*, a* and b*) of heartwood of hinoki half-sib families in a progeny test stand. The survival days of termites and the mass loss of samples of hinoki heartwood differed significantly among hinoki families. Families with red-color heartwood had larger termite resistance than families with yellow-color heartwood. The termite resistances of individual samples from two families with yellow-color heartwood were as small as that of Pinus densiflora. Larger a* and smaller b* induced larger termite resistance of heartwood. The effect of DBH (diameter at breast height) of hinoki trees on termite resistance of hinoki families was small. 相似文献
10.
Wei Wang Yuichi Hanai Chisato Takenaka Rie Tomioka Kazuya Iizuka Hajime Ozawa 《Journal of Forest Research》2016,21(5):251-258
Absorption of radiocesium (137Cs and 134Cs) through bark, and its subsequent translocation into wood and needles, has been suggested as a potential source of tree contamination, but the process is not well understood. Field experiments were conducted to confirm whether Cs could enter a Japanese cedar tree through the bark and how Cs moves within a tree. Stable Cs (133Cs) was applied to the bark at 1.2-m height on 10- and 26-year-old Japanese cedars. The 133Cs concentrations were determined in the bark, sapwood, and heartwood (for 26-year-old cedar only) of stem disks from several heights, as well as in current-year needles from the canopy. The 133Cs concentrations were considerably higher in the sapwood and heartwood of stem disks from 1.2-m height in treated trees than in untreated trees, suggesting that 133Cs penetrated the bark to enter the wood. The average 133Cs concentrations were higher in the heartwood than the sapwood, indicating 133Cs accumulation in the heartwood. High 133Cs concentrations in the needles of treated trees implied acropetal movement of 133Cs to actively growing organs. Our results demonstrate that Cs can enter Japanese cedar trees through the bark and that Cs is transported radially to the heartwood and vertically to the apex. 相似文献
11.
Tamon Yamashita Nobuhiko Kasuya Sen Nishimura Hiroshi Takeda 《Forest Ecology and Management》2004,200(1-3):215-226
Japanese cypress (Chamaecyparis obtusa Endl.) and Japanese cedar (Cryptomeria japonica D. Don) are common species for plantation forestry in Japan. Cypress is conventionally planted on sites of low fertility whereas for cedar high fertility sites are used. Objectives of this study were to compare the productivities of cypress and cedar plantations grown on adjacent sites where common properties of soils, such as pH values and C and N contents, were similar, and to relate the N cycling at their site with productivities. The stem diameter of trees, aboveground litter production and fine root biomass were measured as indices of forest productivity. Parameters of N cycling included pools of total N and mineral N (ammonium + nitrate), annual N leaching, and potentially mineralizable N. The radial stem increment of the two tree species was similar. However, cedar site had higher total basal area and annual basal increment than cypress site reflecting higher tree density on the cedar site. Aboveground litter, fine root biomass, soil organic matter, and N turnover were higher on the cedar site than on the cypress site. However, litter production and fine root biomass per unit basal area was greater at the cypress site. Phenological pattern of stem growth and periodical litter production were similar for both species during the study period (1992–2000), but showed distinct annual variations caused by the fluctuation in the ambient temperature and precipitation. Mineral N content and the N mineralization potential were greater on the cedar site, indicating greater N availability and higher total tree productivity at the cedar site than those at the cypress site. When provided with more space in the canopy to expand more needles and in the soil to develop more fine roots to exploit sufficient resources, the individual cypress trees have the potential to grow faster. On fertile site and at lower tree density, thicker logs of cypress might be yielded. 相似文献
12.
The aim of this study is to characterise the properties of juvenile and mature heartwood of black locust (Robinia pseudoacacia L.). Content, composition and the subcellular distribution of heartwood extractives were studied in 14 old-growth trees from
forest sites in Germany and Hungary as well as in 16 younger trees of four clone types. Heartwood extractives (methanol and
acetone extraction) were analysed by HPLC-chromatography. UV microspectrophotometry was used to topochemically localise the
extractives in the cell walls. The natural durability of the juvenile and mature heartwood was analysed according to the European
standard EN 350-1. Growth as well as chemical analyses showed that, based on extractives content, the formation of juvenile
wood in black locust is restricted to the first 10–20 years of cambial growth. In mature heartwood, high contents of phenolic
compounds and flavonoids were present, localised in high concentrations in the cell walls and cell lumen of axial parenchyma
and vessels. In juvenile wood, the content of these extractives is significantly lower. Juvenile wood had a correspondingly
lower resistance to decay by Coniophora puteana (brown rot fungus) and Coriolus versicolor (white rot fungus) than mature heartwood. 相似文献
13.
G. Von Cerny 《Forest Pathology》1973,3(4):214-220
Inhibition of several ectoenzymes of Fomes annosus (Fr.) Cke. by wood and bark extracts from Picea abies (Karst.). Methanol soluble extractives of sapwood, heartwood and reaction zone from Norway spruce as well as acetone soluble extractives of spruce bark were tested at a concentration of 0.05 percent for inhibition of Fomes annosus enzymes cellulase, pectinase 相似文献
14.
Kazuya Iizuka Narumi Toya Jyunichi Ohshima Futoshi Ishiguri Naoko Miyamoto Mineaki Aizawa Tatsuhiro Ohkubo Chisato Takenaka Shinso Yokota 《Journal of Wood Science》2018,64(1):59-64
To utilize forest resources in areas affected by fallout from the Fukushima Daiichi Nuclear Power Plant accident, it is important to understand the mechanisms of 137Cs movement through the stem wood of contaminated trees. Understanding the mechanism of absorption and migration of 137Cs to stem wood is necessary for clues to the future prediction of the transition of 137Cs to xylem. In the present study, radial variations in 137Cs concentration were investigated in Japanese cedar (Cryptomeria japonica D. Don) trees collected 1 year and 10 months after the accident. Additionally, the relationship between 137Cs concentration and potassium (K) content was established. Trees with a higher moisture content and lower lightness value in heartwood tended to have a higher 137Cs concentration in the heartwood. In these trees, 137Cs concentration peaked at the heartwood–sapwood boundary and gradually decreased toward the pith. By contrast, K content within the heartwood remained nearly constant along the radial direction. The heartwood-to-sapwood ratio of 137Cs concentration was significantly positively correlated with that of K content. Based on these results, we suggest that 137Cs movement from sapwood to heartwood might be related to the K content ratio of heartwood and sapwood. 相似文献
15.
Yutaka Kataoka Makoto Kiguchi Takeshi Fujiwara Philip D. Evans 《Journal of Wood Science》2005,51(5):531-536
Low density wood is more rapidly eroded than denser wood when exposed to the weather, possibly because it is more susceptible
to photodegradation. Fourier transform infrared microscopy was used to examine: (1) the depth of photodegradation in earlywood
and latewood of sugi (Japanese cedar) and earlywood of hinoki (Japanese cypress) exposed for up to 1500 h to artificial sunlight
emitted by a xenon lamp (375 W/m2 within the 300 to 700 nm spectral range); and (2) the relationship between the density of wood tissues and depth of photodegradation.
The depth of photodegradation varied between species (sugi and hinoki) as well as within a growth ring (sugi earlywood and
latewood), and there was an inversely proportional relationship between depth of photodegradation and wood density. These
findings may explain why low density earlywood is more rapidly eroded than latewood during weathering, and more generally,
why there is an inverse relationship between the density of wood species and their rate of erosion during artificial and natural
weathering.
Part of this work was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, August 2004 相似文献
16.
Summary The dissolution and dispersion of components from Norway spruce (Picea abies) wood were examined in laboratory experiments to determine the factors influencing variations in dissolved and colloidal substances in mechanical pulp suspensions. Finely ground, fresh spruce wood was suspended in water at 90 °C and was agitated intensively for up to 12 h, after which the concentrations of dissolved and dispersed lipophilic extractives, lignans, carbohydrates and lignins were determined. Sapwood and heartwood were studied separately. Effects of pH and added electrolytes on the dissolution and dispersion of wood components were also investigated.Higher amounts of lipophilic extractives, and especially of triglycerides, were dispersed from sapwood than from heartwood. The release of lipophilic extractives continued for up to 3 h, after which the concentrations in the suspensions leveled off. At this stage the composition of the dissolved and dispersed lipophilic extractives equaled that of the wood. The amount of lipophilic extractives in the suspensions increased with increased pH, in the range of 4.5–6.7, but was lower in the presence of electrolytes. The dissolution of carbohydrates continued even beyond 3 h of agitation. The high water temperature induced hydrolytic reactions, thereby releasing especially arabinose. The release of arabinose through the hydrolytic cleavage from polysaccharides was more extensive at pH 4.5 than at pH 5.5 and 6.7. More polysaccharides containing galacturonic acid units (pectins) were dissolved at a higher pH. Much more polysaccharides containing glucose, most probably starch, were present in the sapwood suspensions. The dissolution of lignins also continued throughout the 12 h experiment. The measured UV-absorption, after extraction of lignans, was roughly the same for sapwood and heartwood suspensions. Slightly less lignins were released in the presence of electrolytes. Lignans were released only from heartwood. 相似文献
17.
研究长白鱼鳞云杉、臭冷杉的木材及其抽出物化学组成，并分析生材与气干材、心材与边材中各种化学组成变化的规律。同时检测出抽出物中弱酸性物质、中性物质和强酸性物质的含量及弱酸性物质中树脂酸和脂肪酸的组成含量。 相似文献
18.
Quantitative determination of cyproconazole by gas chromatography–mass spectrometry (GC/MS) analysis was investigated. The results suggest that cyproconazole determination is significantly affected by wood extracts. In the presence of methanol extracts of Japanese cedar (Cryptomeria japonica) heartwood, cyproconazole showed 50 % larger peak area than that without the extracts. This phenomenon whereby contaminants in the sample solution affect the intensity of the peak signal is known as the matrix effect. An investigation for eliminating the matrix effect revealed that adding sorbitol as an analyte protectant drastically increased the analyte peak intensity and successfully mitigated the matrix effect of the wood extracts. Adding hexaconazole as an internal standard was also useful in reducing the deviation of the data. The efficacy of a novel sample preparation method consisting of adding sorbitol and hexaconazole as analyte protectants and the internal standard, respectively, were applied to the GC/MS analysis of cyproconazole in the presence of wood extracts of the other nine species. It is revealed that cyproconazole can be precisely determined by GC/MS analysis in combination with the analyte protectant and the internal standard. 相似文献
19.
W. E. Hillis 《Wood Science and Technology》1971,5(4):272-289
Summary In the future, wood will be used largely for the manufacture of fibre products and particle board. The quality of wood used to meet increasing world demand will vary considerably. One feature of quality that can affect utilisation is the amount and type of wood extractives present. The distribution and variation in composition of extractives in the tree, as well as their effect on pulp manufacture, durability and surface films, are summarized. Methods to reduce the effects of some extractives in existing trees are described. Extractives can be reduced in plantation material by minimizing heartwood formation and by using silvicultural methods which result in small amounts of extractives being formed in this tissue. Current knowledge on heartwood formation is summarized.Paper presented to the 3rd Plenary Meeting of the International Academy of Wood Science held at the N. C. State University, Raleigh, March 11, 1971. 相似文献
20.
Akio Inoue 《Journal of Forest Research》2009,14(5):268-275
An allometric model of the maximum size–density relationship between mean stem surface area and stand density is proposed,
and is fitted to data for even-aged pure stands of Japanese cedar (Cryptomeria japonica D. Don) and Japanese cypress (Chamaecyparis obtusa Endl.). To derive the model, the biomass density was defined as the ratio of the mean stem surface area to the side area
of an imaginary column, of which radius and height were equal to the radius of the mean area occupied by a tree and mean tree
height, respectively. According to the model, the slope of the maximum size–density relationship on logarithmic coordinates
can be estimated from the allometric power relationships of mean tree height and biomass density to mean stem surface area.
The resulting slope was −1.089 for the cedar and −0.974 for the cypress. The estimated maximum size–density relationship corresponded
well with the combinations of mean stem surface area and stand density for the overcrowded stands of cedar and cypress. The
steeper slope for cedar was attributed to the allocation of more resources to height growth compared to cypress. The maximum
total stem surface area was approximated to be 1.483 ha/ha for cedar and 0.949 ha/ha for cypress stands. The difference in
the maximum total stem surface area between the two species was produced by the characteristics related to tree height and
stem biomass packing into space already occupied. 相似文献