无锡市古树名木保护

本文讨论了无锡市区古树名木的种类、数量和树龄组成,结合立地条件、生长状况的调查就进一步保护进行了探讨。       

The effect of the interaction of tree slenderness and relative height with ring width on wood density in <Emphasis Type="Italic">Abies balsamea</Emphasis> and <Emphasis Type="Italic">Picea glauca</Emphasis>

Wood density affects the strength of lumber and paper products. Despite considerable research, however, the key factors influencing wood density are still not fully understood. The aim of this study was to analyze the effects of variables within and among trees on the density of current wood growth along the stem in order to further understanding and prediction of wood quality. Correlation analyses together with linear mixed effects and randomForest modelling were carried out using stem analysis and tree-level data from long-term balsam fir and white spruce stand density experiments in Eastern Canada. Wood density showed highly structured patterns of variation among trees. Mixed effects and randomForest models, which incorporated tree-level effects accounted for much of the wood density variation. The three most influential variables identified by randomForest analysis for both species were tree slenderness, relative height and ring width. Wood density increased with slenderness and relative height, and these variables affected relationships of wood density to ring width. Wood density is associated with interacting variables within and among trees including tree slenderness and relative height. Wood density is related to ring width, but this relationship is modulated by tree-level influences which likely reflect mechanical stability requirements.     

竹木复合积成方材生产工艺初探

以小径杉木及制材后的边皮经梳解获得的木束条和刨切薄竹加工过程中产生的废竹片为原料,选用酚醛树脂胶黏剂,探讨了竹木复合积成方材生产工艺并测试其物理力学性能.结果表明,生产工艺可行,竹木复合积成方材强度与竹木混杂比和密度密切相关,其产品材质较均匀,具有较好的物理力学性能,可广泛用于家具、地板和建筑结构材等领域.     

木质基包装材料在果蔬保鲜中的应用

由于木质基保鲜包装材料的结构特点,它可以调节果蔬运输、贮藏过程中的气氛,改善贮藏环境。利用木质剩余物可制得各种形态木纤维,并通过在木浆内添加、表面涂覆或者与其他保鲜材料复合等方法可以制得各种木质基包装保鲜材料。目前木质基保鲜包装材料研究较多的主要有中草药保鲜纸、SO2保鲜纸、抗菌纸和复合型保鲜纸等,而且都取得了一定的研究成果。木质基保鲜材料的研究,应该向着发展高效保鲜剂和专用保鲜材料等方向发展。     

人工经济林木材性质研究

对重要人工经济林树种核桃、枣木、银杏、板栗、樟树和橡胶等木材解剖、物理力学、化学性质进行研究。结果表明 :核桃、银杏、樟树生长速度较快、材质好 ,是培育经济和用材两用林的优良树种 ,枣木和板栗材质好、生长慢 ,可以选择经济林果用为主、材用为辅的培育方式 ;核桃、橡胶、樟树和银杏的密度和力学强度较大 ,板栗和枣树木材的密度和力学强度很大 ;樟树、银杏和橡胶木材的纤维素含量与杨木接近 ,木质素含量界于杨木和马尾松之间 ,且纤维形态特征符合造纸用材的要求 ,树干和加工剩余物可以用于造纸 ;人工经济林枣木基本密度、核桃木材纤维长度可以通过生长轮年龄来预测 ,且预测效果显著。     

木材及人造板物理力学性能无损检测技术研究的发展与展望

无损检测是指不改变被检测构件的最终使用性能,而又能获得所需检测资料的一种测试手段,许多方法都属于这一领域。文中论述了国内外木材及人造板物理力学性能无损检测技术研究的发展历史、研究现状与发展趋势,着重介绍了国外同行在此研究领域做出的贡献,以便为今后国内木材及人造板物理力学性能无损检测技术的研究提供借鉴。     

Influence of deformability of kraft pulp fiber surface estimated by force curve measurements on atomic force microscope (AFM) contact mode imaging

Attempts were made to obtain high-resolution images of an unbeaten bleached softwood kraft pulp fiber surface in water by applying contact mode atomic force microscopy. However, clear topographic images could not be obtained. In order to investigate the possibility of deformation of a pulp fiber surface during scanning, force curve measurements were applied to pulp fiber surfaces. It was found that a pulp fiber in water had a more deformable surface than an air-dried pulp fiber in air. Moreover, the spring constant of it was estimated to be close to that of a cantilever applied for imaging. Therefore, the images of a pulp fiber surface in water were thought to be significantly affected by deformation, which was considered to be an important cause of the unclear images. Parts of this article was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, Japan, March 2003, the 54th Annual Meeting of the Japan Wood Research Society, Hokkaido, Japan, August 2004, the 12th International Symposium on Wood and Pulping Chemistry, Madison, USA, June 2003, and the 13th International Symposium on Wood, Fiber and Pulping Chemistry, Oakland, New Zealand, May 2005     

Analysis of chemical structure of wood charcoal by X-ray photoelectron spectroscopy

Wood charcoal carbonized at various temperatures was analyzed by X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffractometry to investigate the changes of chemical structures during the carbonization process. From the infrared spectra, the carbon double bonds and aromatic rings were seen to form at a carbonization temperature of about 600°C. From the XPS spectra, the ratio of aromatic carbons increased in the temperature range 800–1000°C and over 1800°C. The condensation of aromatic rings proceeded as carbonization progressed. The drastic reduction of electrical resistivity of charcoals was observed in almost the same temperature range. It was found that the condensation of aromatic rings had some relation to the decline in electrical resistivity. Wood charcoal carbonized at 1800°C was partly graphitized, a finding supported by the results of X-ray diffraction and XPS. The functional groups containing oxygen diminished with the increase in carbonization temperature.This paper was presented at the 45th Annual Meeting of the Japan Wood Research Society in Tokyo, April 1995 and at the 47th Annual Meeting of the Japan Wood Research Society in Kochi, April 1997     

Hygroscopicity of wood impregnated with linseed oil

Summary The reduction in hygroscopicity as spruce wood is impregnated with linseed oil may be accounted for using a molecular exclusion model. On the basis of the model, each linseed oil molecule appears to displace 90 water molecules and occupy 6 hydrogen bonding sites in the wood.Dr. Allen R. Sharp, Associate Professor of Physics at the University of New Brunswick and Dr. Christen Skaar, Professor of Wood Physics at Virginia Polytechnic Institute and State University freely gave essential advice and encouragement during this work. Graphical depiction of the molecular displacement model (Fig. 1) was suggested by Dr. Skaar. Much of the experimental work was carried out by Mr. Wu-Rong Perng, Scientific Technician in Wood Science and Mrs. Monica Snow, Instructor in Wood Science at the University of New Brunswick     

Effect of aluminum compound addition on graphitization of wood charcoal by direct electric pulse heating method

The catalytic effect of aluminum on graphitization of wood charcoal was examined. Wood charcoal impregnated with aluminum triisopropoxide to various levels was subjected to direct electric pulse heating. Electric conductivity and heat conductivity of the products showed strong, systematic dependence on the amount of aluminum added. X-ray diffractometry indicated that these effects result from a larger degree of graphitization. Because the amount of aluminum in the final product was negligible, aluminum, before being lost by vaporization, apparently catalyzed graphitization at a lower temperature than is used for conventional treatments.Part of this report was presented at the 17th Annual Meeting of the Association of Wood Processing and Technology, November 1999; the 11th MRS-J Annual Meeting, Kawasaki, December 1999; and the 50th Annual Meeting of the Japan Wood Research Association, April 2000     

大力发展木材防腐，节约木材

本文分析了我国木材防腐的现状，并着重从建筑木材防腐，人工林木腐，木材，竹材的蓝变菌和霉菌防治，以及新型防腐剂的研究与发展等四个方面探讨了在新世纪初我国木材防腐的发展方向。     

Erratum to: Experimental analysis of the response of fresh wood stems subjected to localized impact loading

Wood Science and Technology -     

Data bank of rDNA-ITS sequences from building-rot fungi for their identification

Wood Science and Technology -     

木丝杆定向层积材试制与前景展望

提出木丝杆定向层积材概念,研究以木丝杆为单元制造重组木。采用两种不同规格木丝杆单元和不同铺装方法制作木丝杆定向层积材并进行性能测试,结果表明:增加木丝杆长度有助于提高板材抗弯弹性模量;随机定向铺装的板材抗弯强度优于砖墙式定向铺装。     

黄土丘陵沟壑区刺槐燃料型能源树种造林试验初报

利用当地的2个刺槐品种与引进的2个刺槐品种进行留茬试验,通过造林成活率、苗高、地径、萌生株数及生物量对比分析,筛选出速生、萌芽能力强且生长良好的刺槐能源树种,为当地大力发展刺槐能源林提供理论依据。     

32个杉木无性系木材密度和力学性质的变异*

３２个杉木无性系间，木材密度和抗弯弹性模量、抗弯强度、顺纹抗压强度均有较大差异，无性系内株间亦存在一定差异。木材密度与抗弯弹性模量、抗弯强度、顺纹抗压强度间的相关极显著，相关系数分别为０．３９５７、０．８３６８和０．９０２０；木材密度与生长速度呈负的遗传相关。     

Removal of mercury and other metals by carbonized wood powder from aqueous solutions of their salts

Sugi (Cryptomeria japonica D. Don) wood powder was carbonized at varying temperatures and used as a material to remove heavy metals from their aqueous solutions. Single solutions of mercuric chloride and mixed aqueous solutions containing lead nitrate, arsenic chloride, and cadmium chloride as well as mercuric chloride (1, 5, and 10 ppm) were prepared to determine the efficiency of removing heavy metals by these materials. Wood powder and carbonized wood at 200°, 600°, and 1000°C removed mercury within the concentration range 1–10ppm; mercury was preferentially removed even when mixed with other heavy metals. Wood powder carbonized at 1000°C achieved the best removal of heavy metals among the wood-based materials and even commercial activated carbon in both single and mixed solutions.This paper was presented at the 45th annual meeting of the Japan Wood Research Society in Tokyo, April 1995     

韩城花椒木腐病的危害调查与防治

通过对花椒木腐病的发生及危害进行定期观察总结,并对所得数据进行分析,得出韩城市花椒木腐病危害与树龄、树势、坡向、伤口和管理水平之间有着密切的关系,并提出相应的防治建议,为木腐病的防治提供借鉴。     

An analysis of Greek wood and wood product imports: Evidence from the linear quadratic aids

The consumption of wood and wood products in Greece is based greatly on imports necessitating every year a great proportion of public expenditures. The study of wood and wood product imports consequently, is important to the national economy and can be a useful guide for the forest farms, wood industries and wood firms. In this paper the Greek aggregate import demand for Unprocessed wood (such as logs) Processed wood (such as sawn wood), Veneer Crafts (such as veneer sheets) and Wood Manufactures during the period 1969–2001 is empirically analysed using the linear approximation of quadratic AIDS (QUAIDS) model. Imports of Unprocessed wood, Veneer Crafts and Wood Manufactures are found to be price-elastic, in contrast to Processed wood imports. Processed wood, Veneer Crafts and Wood Manufacture imports are found to be expenditure-elastic while Unprocessed wood is found to be an inferior good. Substitution possibilities are found to be significant between Veneer Crafts and all the remaining wood imports and between Processed wood and Unprocessed wood.     

新型木塑复合材料成型工艺的研究

木塑复合材料是以木材或各种木质纤维素纤维材料为基体 ,通过与塑料以不同复合途径形成的一种新型材料。文章介绍了平压法木塑复合材料成型工艺 ,研究了成型过程中板坯的流动性和粘结性 ,探讨了塑料与木质碎料的混合比对木塑复合材料力学性能的影响。结果表明将塑料先加入一定量的木粉或将木质材料与混炼后的塑料混合后压制成型 ,材料可以具有良好的力学性能