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Regulation of applied-hormones on tension wood formation in Fraxinus mandshurica Rupr. var.japonica Maxim. seedlings gravitational response
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作者 JIANG Sha XU Ke REN Fan-ping ZHENG Shu-xin GU Song 《Journal of Life Sciences》 2008年第5期34-44,共11页
We investigated the role of GA3, uniconazole-P and IAA on tension wood formation, in particular the vessel features, in Fraxinu smandshurica seedlings. Ninety seedlings were used and treated with applications of GA3 a... We investigated the role of GA3, uniconazole-P and IAA on tension wood formation, in particular the vessel features, in Fraxinu smandshurica seedlings. Ninety seedlings were used and treated with applications of GA3 and/or IAA to the apical bud of the stem using a micropipette. Applications of GA3 or GA3 plus IAA with uniconazole-P strongly increased cell number of tension wood in comparison to that of no-uniconazole-P-applied, indicated that GA3 is more efficient than IAA on xylem cell production. Wood quality was also regulated by relative concentration ratio of GA3 to lAA, because of the vessel elements differentiation, density and size were controlled by GA3 and/or IAA on the different levels. These results suggested that the relative concentration ratio of GA3 to IAA and interactions of them are essential in regulating both wood quality and wood quantity, and tension wood formation in this species. 展开更多
关键词 Fraxinus mandshurica Rupr. var.japonica Maxim.Seedlings interaction PGR tension wood formation vesselfeatures
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Acoustical Properties of Acetylated Wood
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作者 Roger M. Rowell 《Journal of Chemistry and Chemical Engineering》 2013年第9期834-841,共8页
Many of the traditional woods used for musical instruments have been selected not only for their natural beauty but for the high content of waxes and resins that help increase water repellency of the wood but have lit... Many of the traditional woods used for musical instruments have been selected not only for their natural beauty but for the high content of waxes and resins that help increase water repellency of the wood but have little or no effect on stabilizing dimensions or vibrational properties. Moisture changes have a great negative effect on both the musical quality of wooden musical instruments and limit the length of time they can be played without loss of musical quality. It is possible to stabilize both the wood and the vibrational properties by chemically modifying the wood. One technology that can do this is the reaction of wood with acetic anhydride. Acetylation of wood slightly increases density, and slightly (about 5%) reduces both sound velocity and sound absorption when compared to unreactedwood. Acetylation does not change the acoustic converting efficiency. Acetylation reduces the amount of moisture in the cell wall decreasing the effect of moisture on the viscose properties of wood. This allows a wooded musical instrument to be played longer without having to let it dry out. This gives an instrument made from acetylated wood a greater range of moisture conditions it can be played in without losing tone quality. Acetylation also greatly stabilizes the physical dimensions of the wood. The major effect of acetylation of wood, therefore, is to stabilize acoustic properties. The technology can be applied to almost any wood though more easily to permeable types so non-traditional wood species can be used. A violin, a piano soundboard, a guitar, a recorder, a bagpipe chanter, and trumpet and trombone mouthpieces have been made using acetylated wood with very positive results. Several more wooden instruments made from acetylated wood are presently being made for further testing and early market development. 展开更多
关键词 Acoustic properties ACETYLATION VISCOELASTIC ANISOTROPIC hydroscopic VIOLIN piano soundboard.
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An Experimental Investigation of Fluidized Bed Gasification of Biomass Blended from Wood, Miscanthus, Straw and other Industrial Bioresidues
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作者 Ling He Kati Geffers Matthias Gohla 《Journal of Agricultural Science and Technology(B)》 2012年第10期1109-1118,共10页
In order to identify potential wood substitutes for the production of energy by gasification, binary blends (wood/miscanthus, miscanthus/straw and wood/straw) and ternary blends (wood, miscanthus and organic residu... In order to identify potential wood substitutes for the production of energy by gasification, binary blends (wood/miscanthus, miscanthus/straw and wood/straw) and ternary blends (wood, miscanthus and organic residue) were systematic tested in a laboratory bubbling fluidized bed gasification system. The results of experiments were compared with results of wood gasification. Of the binary blends, wood and miscanthus exhibited great potential as a wood substitute in fluidized bed gasification in terms of process stability and product gas quality. Adding 10 wt. % of organic residues to form ternary blends further improved the product gas quality. Gasification of fuels blended with straw tended to agglomerate in the fluidized bed because of straw's low ash melting temperature. This can be counteracted by adding Ca(OH)2 to fuels. Nonetheless, fuels blended with straw with higher percentages of Ca(OH)2 need further study to establish the optimal additive ratio. 展开更多
关键词 Fluidized bed gasification blended biomass WOOD STRAW MISCANTHUS industrial organic residues.
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What Is Important in Selecting Phlebiopsis gigantea Strain for Commercial Use?
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作者 Zbigniew Sierota Justyna Anna Nowakowska +3 位作者 Katarzyna Sikora Marta Wrzosek Anna Zolciak Monika Malecka 《Journal of Agricultural Science and Technology(B)》 2015年第1期55-64,共10页
Phlebiopsis gigantea strains registered in the European Union as biocontrol agents against root rot in forests (four from Great Britain and two from Finland) were compared using Ward's method with reference to: (... Phlebiopsis gigantea strains registered in the European Union as biocontrol agents against root rot in forests (four from Great Britain and two from Finland) were compared using Ward's method with reference to: (l) similarity of DNA-random amplified microsatellite (RAMS) ladders, (2) cellulase and peroxidase production and (3) acceleration of dry mass wood loss in Norway spruce The activity of the enzymes was tested in the initial phase of wood decay (30 d after inoculation) and indicated as the most active isolates: VFI0 and FCl5 for cellulase and FC16 and VFI0 for peroxidase production. The assessment of loss of wood six months after inoculation indicated isolate FC 15 as the most active. P. gigantea isolates similar in terms of enzyme activity indicated different patterns ofDNA microsatellite loci. At the same time, DNA-RAMS revealed similarities in isolates with different abilities to produce enzymes. However, some similarities and differences between isolates according to wood decay were found. No plain relationships between molecular characteristics and enzyme activity of the strains tested were observed. The results differentiated activity of tested isolates and suggested benefits of selecting P. gigantea strains for commercial use basing mainly on the assessment of wood loss activity. 展开更多
关键词 Phlebiopsis gigantea isolates DNA-RAMS enzyme activity Norway spruce wood loss Ward's Euclidean dendrograms.
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谈谈广西偏远土质山区脱贫的途径
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作者 蒋朝福 《疏导》 2000年第3期63-64,共2页
关键词 山区脱贫 偏远山区 小型水电站 乡村公路 植树造林 科技人员 用材木 广西 党和政府 教育落后
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Characterization the Reaction of Isocyanate and Cellulose by XPS
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作者 GAOZhenhua GUJiyou LIZhiguo 《Chinese Forestry Science and Technology》 2004年第2期41-48,共8页
The X-ray photoelectron spectroscopy (XPS) technique was used to study the reaction ofphenyl isocyanate and cellulose with different moisture contents (MC). The C1S XPS peak of cellulose isonly one symmetrical contrib... The X-ray photoelectron spectroscopy (XPS) technique was used to study the reaction ofphenyl isocyanate and cellulose with different moisture contents (MC). The C1S XPS peak of cellulose isonly one symmetrical contribution at 285.95 eV. While the C1S XPS peaks of N,N-dibenzylurea, thereaction resultant of phenyl isocyanate and water, have two contributions at 288.6±0.1 eV and 284.7±0.1 eV corresponding to the carbonyl group and phenyl ring group, respectively. Their area ratio isbetween 11.88 and 11.98 that is quite neat to the theoretical value of 12.0. With the moisture content (MC)of cellulose increased, the proportion of isocyanate reacted with water increased. When the MC reaches 9.78%, 92.98% of all consumed isocyanate will react with water. By spattering analysis, it reveals that thereaction resultants of benzyl isocyanate distribute mainly on the surface of cellulose. 展开更多
关键词 benzyl isocyanate CELLULOSE moisture content competitive reaction ESCA analysis
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