共查询到18条相似文献,搜索用时 828 毫秒
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简述了森林吸收二氧化碳的碳汇作用,着重列举了在木材加工过程中,如木材干燥、制材、木材防腐及人造板加工中废旧木材的回收利用等各个环节,如何提高木材利用率,减少森林的砍伐量,以实现木材加工过程的低碳经济。如果干燥量为10万米。的木材,原来降等损失是10%,改进木材干燥的设备和干燥工艺使降等损失减少5%,砍伐量将减少1.25万米。,那就可以多吸收2.29×10^4吨的二氧化碳,同时多放出2.02×10^4吨的氧气;制材工序若出材率提高12%,每年可以减少原木砍伐量700万m^3左右,可增加碳汇量1281万吨,多放出氧气可供1512万人所需的氧气。同样,提高我国木材防腐处理的比例、加大人造板加工中废旧木材的回收利用比例,都可以明显减少森林的砍伐量,对低碳经济做出贡献。 相似文献
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木材溶剂液化技术及其在制备高分子材料中的应用 总被引:3,自引:0,他引:3
木质材料经过热化学液化,可进一步制备酚醛树脂、聚氨酯等高分子材料.本文介绍了木材液化技术制备高分子材料的发展状况,包括液化方法、木材主成分的液化机理以及液化生成物的应用,指出在木材液化反应机理、液化产物的利用和最佳液化工艺的开发等方面尚有待进一步研究,并提出充分利用木材的生物降解性,开发木材液化物与其他材料复合的新型高分子材料具有广泛的前景. 相似文献
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玻纤增强发泡聚氨酯合成木材 总被引:2,自引:0,他引:2
我国木材资料短缺,优质木材资源尤为缺乏,为了节省自然资源,大力开发人工木材,是发展的一种趋势.聚氨酯泡沫塑料具有密度小、隔热性好和成型简便等优点,但纯聚氨酯泡沫塑料(硬质)与木材相比,其弯曲、冲击强度等指标都低,因而限制了它的使用.为了弥补这一缺陷,我们采用玻纤增强的方法,来提高它的强度.国内关于玻纤增强发泡聚氨酯合成木材的研究、开发尚未见报导,国外已有这方面的成熟技术.据资料介绍,80年代初,日本铁道综合技术研究所,研制成功玻纤增强发泡聚氨酯铁道枕木,并用此枕木作了 相似文献
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本文阐述了国内外木材胶粘剂的进展,广东省木材胶粘剂的生产,应用状况和存在问题,提出了广东省木材胶粘剂的发展对策。 相似文献
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AbstractBeech wood has a high frequency of defects such as red heartwood, reaction wood (tension wood). For the experimental measurements four logs without visible defects like red heartwood, which can noticeably affects the measurements' results were qualified. The drying medium temperature in the first phase of the process before the moisture content of the specimens fell below the FSP was maintained at 45?°C. Then, the temperature was gradually increased to the maximum value 65?°C. The results showed that different initial wood moisture content does not affect to final value of tension and normal wood. The colorimetric parameter L* was much higher for tension wood. After steaming, there were greater differences in the colorimetric parameters, respectively, a* and b*. After drying the difference of all colorimetric parameters between tension and normal wood was significantly less. The color changes were only noticed in the surface layers of specimens. Differences were small, and thus, the impact of the tension wood on the color changes was not confirmed. However, since the lightness of tension wood plays a key role for its visual detection, it may be adequate to only measure the lightness parameter (L*). 相似文献
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Woodceramics Prepared from Wood Powder/Phenolated Wood Composite 总被引:2,自引:0,他引:2
B.Y. Zhao T. Hirose T. Okabe D. Zhang T.X. Fan K.A. Hu 《Journal of Porous Materials》2002,9(3):195-201
In this paper, composites were made from wood powder and its phenolated product, and then were carbonized into woodceramics. The effects of the content of the phenolated wood in the composites on the forming ability, size, density, compressive strength, volume electrical resistivity, and specific surface area of the woodceramics were investigated. It is suggested that in the preparation of woodceramics, phenolic resin can possibly be substituted totally by phenolated wood that is the main constituent of liquefied wood. 相似文献
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Economic data were obtained from 15 industrial wood burners. The capital cost was correlated by: Cost = $7870 (kW)0.59. Operating cost varied between $ 0.64 and $ 2.65 per kWhr output, payback times between 3.5 and 11 years and internal rates of return between 6.3% and 28%. Using average values of economic parameters, these results were recalculated on a common basis as a function of wood and electricity costs. 相似文献
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三种自制木醋液理化性能比较及棉秆木醋液成分分析 总被引:1,自引:0,他引:1
将棉秆、苍耳秆和西红柿杆三种生物质在管式炉内热解,对获得的生物质油通过三步升温、常压蒸馏法分离出四个流程的馏分,其中第二个馏分(98-103℃)作为目标产物即精制木醋液,对此的物理性能进行了测定比较,采用(GC-MS)分析测定了棉秆精制木醋液的化学成分。经分析得:三种植物的精制木醋液得率范围为37%-41%近似相等,有机酸的含量为7.022%~7.973%,pH为2.98~4.01,有机酸含量均大于7%;棉秆精制木醋液含醋酸26.56%,丙酮37.82%及21.1%的烷烃类,其有机成分比较集中。 相似文献
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木粉对PVC木塑复合材料力学性能影响 总被引:8,自引:0,他引:8
采用电镜扫描观察了3种木粉的纤维细胞尺寸及其木粉微观形态。研究了木粉粒度、微观特性以及木粉添加量对了聚氯乙烯(PVC)木塑复合材料力学性能的影响。结果表明,木粉表面裸露的微细纤维增加和粒度减小,有助于提高木塑复合材料力学强度;加入少量木粉使木塑复合材料力学性能降低,但随着木粉添加量的增大,木塑复合材料的抗弯性能和拉伸强度上升;木塑复合材料的冲击强度随木粉含量增加而下降。 相似文献
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从与建筑涂料、木器涂料相关的产业——建筑、木器家具、木地板及建筑装饰装修行业的发展前景着手,阐述了中国涂料行业运行的特点,并从市场容量及市场竞争格局分析了中国建筑涂料及木器涂料市场状况,预测伴随着建筑、家具、装饰装修等相关产业的不断发展,建筑涂料及木器涂料行业仍将有着良好的发展前景。 相似文献
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Orthotropic drying stresses of tension and normal wood in poplar were evaluated. The degree of residual stresses was interpreted by prong and slice cutting tests. A strain gauge was employed to determine longitudinal drying stresses. Mixed tension/normal wood boards were also dried using three different schedules, T8 F4, T8 F5, and T9 F4 to find the best schedule. Results revealed more intense drying stress in the longitudinal and radial directions of tension wood. Despite a high susceptibility of the mixed tension/normal wood boards to drying defects, the quality of the boards dried by the schedule of T9 F4 was satisfactory. 相似文献