木材影响其胶合强度的诸因素分析

论述了木材与其胶合强度有关的因素,诸如木材的密度、纤维方向、含水率、收缩膨胀率、粘接面特性、抽提物和pH值等对木材胶合强度的影响。     

水性高分子异氰酸酯胶黏剂胶合制备三层实木复合地板初探

采用水性高分子异氰酸酯胶黏剂,以柞木、赛鞋木豆(乌金木)和橡胶木3种木材单板为表板制备杨木芯的三层实木复合地板.结果表明:赛鞋木豆(乌金木)和橡胶木的胶合性能良好,而柞木性能较差,分析认为与柞木木材表面性能以及胶合工艺等有关.     

木材肌理在家具造型设中的表现

木材的肌理特征作为一个基本的外观因素在木家具产品设计中发挥着极其重要的作用。本文概括了肌理及木材肌理的定义,阐述了木材肌理与纹理、花纹、质感、材色几个词语的概念,分析了木材的肌理特征在家具产品造型形态设计中的几方面影响,并提出了对木材肌理进行挖掘和运用的几个方法,从而为木材肌理在木家具产品中的充分表现提供了依据。     

我国木材材种识别技术的新进展

介绍了传统的板材识别方法,包括人工经验识别法、对分式检索表法和穿孔卡片检索表法.总结了基于计算机识别技术的各种木材识别方法:数据库查询检索法、木材图像识别法、利用神经元网络和木材表面颜色特征对木材进行分级的方法、基于语义数据模型的识别方法、基于最大相似原理的材种判别法和木材细胞模型系统的研究进展,重点论述了基于板材端面细胞实体检测图像的数字特征参数识别法.还总结了木材识别理念的更新和进展,指出基于板材端面细胞实体检测图像的数字特征参数识别法大幅度地加快了识别和比较计算的速度,减少了传统依赖图像像素特征识别比较的不确定性.     

Effects of wood fiber content and coupling agent content on tensile properties of wood fiber polyethylene composites

This study investigated the effects of coupling agent content, wood fiber content and wood fiber type on the mechanical properties of wood fiber-reinforced polymer composites (WPC). This study adopted a response surface strategy of a 20 run optimal design for these three factors. The WPC modulus of elasticity was mainly influenced by wood fiber type and wood fiber content, and tensile stress at break depended on wood fiber type, wood fiber content and coupling agent content, whereas strain at break was significantly affected by wood fiber content and coupling agent content, but not significantly influenced by wood fiber type.     

精制杂木木醋液成分分析及其抑菌活性研究

精制杂木木醋液,探讨木醋液成分和再处理后的抑菌活性。通过静置、活性炭吸附相结合法精制杂木木醋液。采用GC-MS(气相色谱-质谱联用仪)技术对精制木醋液进行成分分析。利用滤纸片法测定精制木醋液对大肠杆菌和金黄色葡萄球菌的有效抑菌时间。对精制木醋液进行调pH值、稀释、减压蒸馏、萃取等处理,探讨不同处理方法后木醋液抑制细菌活性的效果。研究结果表明:木醋液对于细菌的有效抑菌时间为24 h;木醋液中的酸性物质影响其抑菌能力;木醋液对细菌的最低抑菌浓度为V精制木醋液:V灭菌水=1:20;60 ℃减压蒸馏抑菌效果最优;萃取木醋液的萃取剂抑菌效果排序为:萃取层>精制木醋液>水层,乙酸乙酯是木醋液的最佳萃取剂。杂木精制木醋液成分主要有酸类、酚类、酮类和醇类等,具有抑菌活性,且再处理后的抑菌活性显著,是一种潜在的生物防腐剂。     

马尾松腐朽材对其硫酸盐法制浆性能的影响

分析马尾松正常材和贮存较久的腐材的化学成分、纤维形态,研究腐朽材对马尾松硫酸盐法制浆、H单段漂白特性以及未漂浆成纸性能的影响。研究结果表明:马尾松腐朽材的制浆造纸性能较差,生产中应该尽可能避免使用腐朽材。     

Influence of chemical modification of wood on the crystallisation of polypropylene

The mechanical properties of wood/polypropylene composites depend strongly on interfacial adhesion between components. However, the application of chemical modification to improve compatibility can influence the supermolecular structure of polypropylene matrix. The experimental material comprised two most common Polish timber species pine wood (Pinus silvestris L.) as a softwood species and beech wood (Fagus silvatica L.) as a hardwood species. The size of wood sawdust ranged from 0.5 to 1.0 mm. Three different types of wood/PP mixture were prepared: (1) PP – untreated wood, (2) PP – NaOH treated wood and (3) PP – esterified wood with maleic anhydride. In this work, the kinetic parameters of crystallization of PP by differential scanning calorimetry were investigated. It is interesting that crystallisation of PP depends on the kind of wood. The chemical treatment of wood caused changes of crystal conversion and half crystallisation time of polypropylene matrix.     

Effect of heat treatment on the wettability of white ash and soft maple by water

Heat treatment of wood has attracted a lot of attention both in Europe and recently in North America as an environmentally-friendly wood-protection method. The untreated wood is hydrophilic (high affinity for water). During the heat treatment, wood becomes more and more hydrophobic (low affinity for water) with increasing heat treatment temperature. As a result, it becomes more resistant to biological attacks. Furthermore, it becomes dimensionally more stable compared to untreated wood. Its hardness increases. As the wood becomes more hydrophobic, its wettability by water decreases. The effect of heat treatment is different for each species. Studying the wetting characteristics of heat treated wood gives a good indication of the heat treatment effects on certain wood properties which are related to its degree of hydrophobic character. The aim of this work was to study the characteristics of dynamic wetting process for two different heat-treated North American wood species white ash (Fraxinus americana) and soft maple (Acer rubrum). Contact angle measurements before and after heat treatment showed a significant increase in wood hydrophobicity. Advancing contact angles of a water drop were in all cases higher for heat-treated wood than for untreated wood.     

木材纹理图案的美学研究

从木材美学研究的现状出发,首先对木材三切面的宏观纹理进行美学分析,阐述木材的自然纹理满足了人们视觉和心理情感的美学需求,接着对木材微观构造进行形式美法则的探讨,深层次地剖析木材微观纹理的美学形式。最后对其微观构造纹理进行图形处理,产生美妙的契合形图案,丰富了现代图案设计的素材库,表达了木材美学研究的重要意义。     

实木顺纹压缩弯曲技术研究现状及发展趋势

实木顺纹压缩弯曲技术蕴含着多学科知识的交叉融合,具有一定的理论深度和突出的实际应用性,是当今备受关注的研究热点之一文章论述了国内实木顺纹压缩弯曲技术的研究现状与发展趋势,描述了国内研究学者在树种选择、木材软化与顺纹压缩、木材弯曲等方面的研究成果,提出高效利用木材资源、提升自动化程度、提高木材弯曲精度的发展趋势,为今后国内实木顺纹压缩弯曲技术的研究提供借鉴。     

柠条正常木与受拉木纤维细胞超微结构及木质素微区分布研究

采用透射电子显微镜（TEM）、扫描电子显微镜-X射线能谱仪（SEM-EDXA）及共聚焦激光扫描显微镜（CLSM）研究了柠条（Caragana korshinskii）正常木与受拉木纤维细胞的超微结构及木质素在细胞壁中的分布。结果表明,柠条正常木纤维细胞壁分为胞间层（ML）、初生壁（P）、次生壁外层（S1）、次生壁中层（S2）、次生壁内层（S3）;而受拉木与正常木不同,其细胞S3层被凝胶层（G层）取代。正常木与受拉木中导管和木射线细胞壁的木质素浓度均比纤维细胞壁的高。正常木纤维细胞各形态区的木质素浓度不同,细胞角隅区的木质素浓度最高,其次是复合胞间层（CML）,S2层最低。柠条受拉木纤维细胞壁中除G层未木质化外,与正常木细胞壁各层木质素分布相似。     

Effects of chemical modification on the mechanical properties of wood

Chemical modification has been recognized as an efficient strategy for dimensionally stabilizing wood and protecting it from environmental damage, such as deterioration due to weathering and fungal decay during the service period. Studies reported in the literature mainly concern the establishment of workable modification techniques, testing methodologies, and assessment of the durability of modified wood. The development of wood modification techniques has recently been reviewed; limited information is however given on the effects of chemical modification on the mechanical properties of wood that are of importance to it as an engineering material. This paper reviews the effects of wood modification, typically by heat treatments and impregnation with low molecular weight resins, reactive monomers, or hot melting paraffins on the mechanical properties of wood. The modifying variables associated with mechanical properties of wood such as wood species, treating temperature and time, catalyst, type of solvent, weight percent gain, and molecular structures of the modifying agent were analysed and the results interpreted. The reasons for changes in the mechanical properties of wood are discussed.     

制浆过程中木片浸渍机理及改善措施

从木片浸渍的基本原理、评价手段和影响木片浸渍效果的因素等方面对木片的浸渍进行了阐述,并重点讨论了加强木片浸渍的措施。     

Strength of wood versus rate of testing

Strength of wood is normally measured in ramp load experiments. Experience shows that strength increases with increasing rate of testing. This feature is considered theoretically in this paper. It is shown that the influence of testing rate is a phenomenon, which depends on the quality of the considered wood. Low quality wood shows lesser influence of testing rate. This observation agrees with the well-known statement made by Borg Madsen that weak wood subjected to a constant load, has a longer lifetime than strong wood. In general, the influence of testing rate on strength increases with increasing moisture content. This phenomenon applies irrespective of the considered wood quality such that the above-mentioned order of magnitude observations between low and high quality wood are kept.     

废旧实木类木材回收利用途径探讨

根据对河北省废旧木材回收利用的调查结果,对废旧实木类木材的利用途径和存在问题进行了探讨.目前河北省废旧实木类木材回收利用的产业链已经自发初步形成,废旧实木类木材主要是用来制作细木工板的芯条,或用来制造木质家具、实木制品、包装材料和建筑构件等.     

木材基布的开发与研制

介绍了木皮的种类,木皮复合基布木材基布的开发及研制过程,并在对非织造布木材基布的技术性能进行了测试的基础上提出的木材基布的使用方法。     

四川芦山地区阴沉木雕刻工艺品产业的发展

考察四川芦山地区阴沉木雕刻工艺品产业的形成与发展,探讨该地区有形木材资源与无形木雕工艺、木文化的融合,同时针对产业发展中存在的一些问题,提出了解决之道。面对不可再生阴沉木资源的逐渐匮乏,有限有序开采十分必要,同时要保护阴沉木的科学信息。面临越来越国际化的市场竞争,应增加产品的透明度,规范产品命名,在经营方式上让消费者切身参与其中,了解木雕艺术作品的制作流程,增强互动性体验性,同时在区域建设上合理配置资源,将休闲娱乐与木文化的传播融为一体。     

国际木工刨床设计新技术综述

本文综述了国际木工刨床先进技术的最新进展,提出了国际数控木工刨床的新动向、四面刨的新结构、刨刀和刀轴技术的新突破、连续化刨削的技术特点等。重点论述国外木工刨床新技术的发展目标,指出实现我国木工刨床的发展方向和新技术研究的总目标,为提出了我国木工刨床新技术的全面开发方案,制订了我国木工刨床新品种的开发战略提供了资料。为我国木工刨床新的改进方向和应该是我们应该注意的问题提供了借鉴。     

CT技术在木材工业中的应用

介绍了作者应用CT技术实现原木内部缺陷的无损检测、原木图象的三维重建和虚拟加工、以及木材内部密度和干燥过程中水分的分布等方面的初步研究成果,并对CT技术在木材科学研究中的一些问题和工业中的应用前景作了探讨.