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生物柴油原料树种文冠果的叶片、枝干、果皮、种皮、种仁中化学成分丰富多样,除了含有细胞壁组分木质素、纤维素、半纤维素、果胶质以及储藏物质蛋白质、糖类、脂肪外,还含有甾体、萜类、香豆素、黄酮类、有机酸以及蒽醌等多类次生代谢产物,具有在食用、药用、饲用、化工、能源等多个领域的开发利用潜力.在对该树种化学成分和综合利用方面的研究进展进行总结分析的基础上,提出了目前存在的问题和需要进一步研发的建议. 相似文献
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杨树是我国重要的速生树种。以杨木为原料制备生物乙醇是解决当今能源问题的一项新的尝试。对杨木原料蒸汽爆破预处理后以及菌处理后的化学成分及化学性质进行了测定分析。通过对比其化学成分(纤维素、木素、半纤维素、抽出物、灰分及蛋白质)的变化,研究了以杨木为原料制备生物乙醇生产过程中化学成分变化机理,旨在为指导杨木制备木质纤维乙醇的生产,并为发酵后副产物的回收再利用提供理论依据。 相似文献
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木材易产生吸湿变形和腐朽等问题,影响其应用效果。热改性处理可有效提升木材的尺寸稳定性和耐久性,并具有无毒、环保的特点,是一种极具潜力的木材改性方法。文中综述了木材组分(纤维素、半纤维素、木质素、抽提物)在热改性过程中发生的化学变化,以及木材树种和部位、处理介质、处理温度和时间对木材热降解的影响。经不同热改性工艺处理后,木材的化学成分变化存在较大差异。探明热改性工艺、热改性材化学成分变化和性能之间的响应机制,将有助于开发或优化热改性技术,从而得到性能优异的热改性材,拓宽其应用领域。 相似文献
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杞柳的化学成分及其木质素微区分布的研究 总被引:1,自引:0,他引:1
采用传统的化学成分测试方法和激光扫描共聚焦显微镜技术(CLSM)研究了杞柳的化学成分以及木质素在各细胞及纤维细胞各微区的分布,分析了株高不同部位化学成分的变异规律。结果表明:杞柳的1%Na OH抽提物、热水抽提物、冷水抽提物、苯醇抽提物、综纤维素、α-纤维素、酸不溶木质素、酸溶木质素、多戊糖和灰分分别为32.11%、10.85%、7.11%、3.27%、70.46%、35.50%、20.18%、4.50%、15.51%、0.90%;在不同部位,除了α-纤维素和多戊糖含量差异不显著,其余各指标均差异显著;木质素在各细胞及纤维细胞各微区分布不均一,导管细胞壁木质素浓度高于木纤维和射线,纤维细胞角隅处木质素浓度高于次生壁和复合胞间层。 相似文献
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FT-IR imaging and pyrolysis-molecular beam mass spectrometry: new tools to investigate wood tissues 总被引:2,自引:0,他引:2
Nicole Labbé Timothy G. Rials Stephen S. Kelley Zong-Ming Cheng Joo-Young Kim Yi Li 《Wood Science and Technology》2005,39(1):61-76
Fourier transform infrared (FT-IR) microimaging spectroscopy and pyrolysis molecular beam mass spectrometry (py-MBMS) were used as rapid analysis tools to evaluate differences in the chemical composition of 1-year-old transgenic aspens. Multivariate analysis of the spectroscopic data sets was used to compare the cell wall composition of nontransformed control to transgenic aspen plants with GRP-iaaM gene and with GRP-iaaM/35S-ACCase gene. Principal component analysis (PCA) was applied to both the FT-IR and py-MBMS spectra, which revealed sample groupings due to differences in chemical composition. Evaluating the PCA loadings allows determination of the chemical features responsible for the groupings. The FT-IR microimaging data was also used to monitor changes in the chemical composition as a function of the distance from the pith to the bark using partial least squares (PLS) analysis. The analysis shows that the changes in the composition of the xylem that occur over one annual growth ring can be monitored with FT-IR microimaging. 相似文献
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闽北山地坡相对湿地松人工林木材化学成分的影响 总被引:1,自引:0,他引:1
应用坡相四个因子在两个水平下的正交试验设计方法,系统分析了19年生湿地松人工林木材化学成分的变化规律,结果表明:影响湿地松人工林木材化学成分的最重要坡相因子是坡形,其次是坡位,再者是坡向,小于45°的坡度的影响可忽略不计。湿地松人工林木材作为纸浆原料和人造板原料,阴坡好于阳坡,凸坡好于凹坡,上坡好于下坡。 相似文献
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The authors reviewed the previous research results about the color changes in heat treated wood,and deeply analyzed the effect of heat treatment method and parameters including temperature and time of heat treatment,species and chemical composition on the color changes in heat treated wood.The relationships between color changes and chemical composition,physical and mechanical properties were found.The optical stability of the color of heat treated wood was studied.Some suggestions were proposed for the future research. 相似文献
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高温热处理对木材颜色变化影响综述 总被引:3,自引:2,他引:1
通过总结热处理对木材颜色变化的研究结果,分析热处理方式、热处理工艺参数包括温度和时间、树种与化学成分对热处理材颜色变化的影响,颜色变化与化学成分以及物理力学性能的相互关系,以及热处理材颜色光稳定性能。对今后研究提出几点建议。 相似文献
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H. Pereira 《Wood Science and Technology》1988,22(3):211-218
Summary The chemical composition of cork from Quercus suber L. was determined for virgin cork and for reproduction cork. Average chemical composition of virgin cork is: ash 0.7%, total extractives 15.3%, suberin 38.6%, lignin 21.7% and polysaccharides 18.2%. The carbohydrate composition shows that glucose represents 50.6% of all monosaccharides, xylose 35.0%, arabinose 7.0% and galactose and mannose, respectively, 3.6% and 3.4%. Reproduction cork has a composition similar to virgin cork. For the cases studied, reproduction cork had however less extractives and a higher amount of suberin. Significant differences were found for the chemical composition of virgin cork in relation to location of extractives and polysaccharide content. The between-tree variability was large and a variation within the tree was also recorded.The author is grateful for the help of collaborators throughout the chemical analysis of the many samples: Joaquina Ferreira, A. Velez Marques, M. Lurdes Ferreira, Rosa Amorim and Célia Constâncio.The work was financially supported by the Instituto de Ciência e Tecnologia dos Materiais (ICTM), Lisbon, Portugal 相似文献