木材干燥理论在木材加工技术中的应用分析

在木材加工技术中,木材干燥理论包括木材平衡含水率理论、木材传热理论、木材水分扩散理论以及木材干燥应力与应变理论。以上几大理论涉及到木材的干燥处理、加工、维护以及强度设计。木材干燥理论在木材加工中具有十分重大的意义。     

木材微生物变色与调控研究现状和展望

木材变色是一种木材材性的缺陷,木材调色是木材变色现象的逆利用。利用微生物调控木材材色环保无污染,具有较好的发展前景。综述了易变色的木材种类、易使木材变色的菌种、微生物控制木材变色和腐朽以及微生物诱导木材调色的研究现状,并对今后木材微生物变色与调控的发展提出建议。     

木材运输现场检查方法若干问题的探讨

论述木材运输现场检查中运输证件与所运输木材的检查方法,着重对木材树种的识别,木材等级与规格的评定,汽车运输木材、船运木材、排运木材的材积计算方法进行探讨,并提出了提高木材运输检查技术水平的途径。     

加强木材运输检查工作的新思路

随着市场对木材需求量的急剧增加,一些不法分子为牟取暴利开始盗伐木材或大肆收购非法来源的木材,这些木材以低价流入木材市场,严重扰乱了市场秩序,影响了林区的社会稳定。为此,木材检查站加强木材运输检查监督,是打击违法运输木材活动,维护正常流通秩序,保证木材市场健康发展不可或缺的手段。     

促进绿色未来的全球木材科学与技术研究进展——国际林联第25届世界大会木材议题综述

国际林业研究组织联盟（IUFRO）第25届世界大会于2019年在巴西召开。文中从木材生长、木材性质与质量、木材识别、木材加工利用和木文化5个方面分别论述了这次大会在木材科学与技术领域的国际最新研究热点与进展，以反映全球木材科学的研究现状，并梳理学科发展方向。木材形成、木材质量、木材高附加值利用、木材识别新技术等议题依然是木材科学与技术领域的未来研究热点。     

木材综合信息数据库查询系统的研究

木材综合信息数据库查询系统是在收集、整理我国木材科学领域多年来研究成果和实验数据的基础上，建立起来的大型木材科学综合信息数据查询应用软件包。系统收录有木材标本、木材译名、木材用途、及木材解剖识别、木材眼微构造、木材化学、木材物理力学、木材、木材热学、木材声学及木材渗透性等信息，建立了十二个专项子数据库。     

木塑复合材料产业发展速度快市场需求旺

随着经济的发展和人口的增加，全球对木材的需求量不断增长，主要木材供应国相继开始显著木材的采伐和出口，木材供需矛盾更为突出。因此在木材的利用上，一方面要尽量减少采伐量，寻找木材的替代品；另一方面要提高木材的利用率。木塑复合材料即为一种有效的木材替代品。     

开展木材美学研究拓宽木材解剖学的应用

该文以探索木材解剖学发展的历史与现状为出发点，比较系统地提出了“木材美学”的理念。为了木材美学的长远发展，该文对木材美学的研究内容进行了初步的系统规划，并从木材宏观美学和木材显微美学两个层面探索性地论述了木材美学的研究方法。该文认为，木材美学的研究应从理论和应用两个方面来开展。在理论方面，现阶段需重点研究木材美学元素和木材美学构成原理；在应用方面，首先需要从美学的角度深入研究木材的宏观与微观构造，并在此基础上广泛开展木材美学图案的创作设计和推广应用研究。该文认为，木材美学具有十分广阔的发展空间和非常诱人的应用前景，木材美学的开创与发展将为传统木材学拓展新的研究领域、带来新的发展空间，可望使木材解剖学焕发新的勃勃生机。     

木材保护领域7项标准通过专审

为加强对防腐木材质量的检验和监督,规范防腐木材市场,2008年9月,中国木材标准化技术委员会在北京进行了6项国家标准和1项行业标准的审定。《木材防腐剂》规定了水载型木材防腐剂的有效成分配比,适用于木材防腐剂的生产及使用。《防腐木材的使用分类和要求》根据木材及其制品在     

木材固碳量与含碳率研究进展

木材碳学是近年来兴起的一门科学, 其主要研究内容包括木材碳素的储存量、木材储能、人工林木材固碳增汇与优质木材培育技术及木质产品固碳延伸等方面。文中简述了木材碳学研究中木材固碳量与含碳率、木材固碳量的影响因素、木材固碳量与木材热值的关系以及木质材料固碳量和固碳延伸等方面的研究现状, 并对今后的研究方向进行了展望。     

毛竹材积主要构件因子关系研究及材积表编制

通过毛竹立竹材积构件因子及立竹胸径与立竹实际材积的关系研究,结果表明:立竹全高、胸高竹壁厚与立竹胸径呈显著的正相关,是立竹胸径的从属因子;竹秆相对高度竹壁厚与秆径呈一致性变化趋势,立竹径级与竹秆相对壁厚无相关;构建了立竹胸径与立竹实际材积的数学模型:V=0.007351-0.001875D+0.000291D2,编制出竹林林分结构易测因子立竹胸径的对应材积表。     

On mechanical behavior of traditional timber shear wall in Taiwan II: simplified calculation and experimental verification

In the previous report of this ongoing study, results of an extensive field survey were collated and a theoretical model was proposed to predict the mechanical behavior of timber shear walls of traditional design in Taiwan. The initial objective of the present report was to propose a simplified calculation method for estimating the initial stiffness and yield strength of traditional timber shear walls. Based on the results of the field survey, a total of 15 full-scale specimens were tested to verify the theoretical model and simplified calculation proposed previously. Good agreement was found from comparison of analytical and experimental results. The results of this study show that the friction behavior between board units and beams plays the major role in resisting the lateral force applied on the timber shear wall, followed by the resistance supplied by embedment. The resistance provided by bamboo nails is minor due to the small section. Another trend found was that for set dimensions of a timber shear wall, the board width can be increased to obtain higher stiffness and strength of the shear wall.     

针叶材在超细粉碎过程中细胞壁断裂的理论计算

将针叶材的超微结构破坏分为细胞壁间分离和细胞壁断裂两种形式。在制备其超细木粉过程中,涉及到针叶材细胞的破壁力计算时,提出以细胞壁中存在大量的原生细观缺陷作为已存在的裂纹,将单一细胞壁看作是带有裂纹体受拉应力的平板,利用弹塑性断裂力学中J积分与积分路径无关这一常数的性质,避开裂纹尖端的弹塑性区域进行理论计算,应用J积分与应力强度因子在平面应力下的关系,计算出针叶材细胞壁断裂韧性的大小,并将不同针叶树种的木材细胞断裂韧性数值与其相应的细胞壁抗拉强度实验结果相比较,得出以此理论计算木材细胞断裂韧性值较为合理,表明利用J积分计算木材细胞壁断裂韧性这一方法是可行的。     

Effective lateral resistance of timber–plywood–timber joints connected with nails

In this study, an experimental study was conducted on the nailed timber–plywood–timber joints extended from the standard wall–floor joints of wooden light frame constructions, where the bottom plates of shear walls are nailed to the floors consisting of joists and floor sheathings nailed to them. The principal conclusions are as follows: The allowable lateral resistance of the nailed timber–plywood–timber joints can roundly be estimated by neglecting the plywood panels if their densities are higher than those of the timber main-members and they are fastened effectively onto the timber main-members. The stiffness of the timber–plywood–timber joints is less than that of the control timber–timber joints, which is improved by increasing the number of nails used to fasten the plywood panels onto the timber main-members. The stiffness of the joints whose floor sheathings are glued onto the joists is equivalent to the control timber–timber joints. The timber–plywood–timber joints with appropriate specifications have greater energy capacity until the failure than that of the control timber–timber joints. This ensures their energy capacity, which is important in dynamic resistance, to be equivalent to the control timber–timber joints.     

群改杨无性系材性性状遗传分析

对22个群改杨无性系的材性和生长性状进行综合评定,分别采用六项指标（纤维长度、壁腔比、纤维长宽比、密度、树高、胸径）评分法和三项指标（纤维性状、木材密度、材积）评分法,探讨了无性系评定方法。     

Rasterelektronenmikroskopische Abbildungen von Hyphen des Birkenporlings (Piptoporus betulinus) im Holz von Betula pendula

Scanning electron micrographs of the hyphae of Piptoporus betulinus in timber of Betula pendula. Hyphae of Piptoporus betulinus (Bull, ex Fr.) Karst. were photographed in naturally infected timber of Betula pendula Roth by means of scanning electron microscopy. The hyphae had an average diameter of 3μm and a cell wall thickness between 0.4 and 0.7 μm. The dissolution of the cell wall by specific fungal enzymes can be extremely well studied using scanning electron microscopy.     

A new proposal to reinforce planked timber shear walls

Timber is one of the most common materials used in traditional buildings worldwide. Our previous research has suggested that timber shear walls play an important role in resisting external loadings, such as earthquakes. Thus, improving the structural performance of in-filled shear walls can also improve that of the entire structure. In the traditional Taiwanese timber shear wall system, the embedment strength of beams and friction between wooden planks and beams significantly affect the strength of the shear wall. This article proposes a new method of reinforcing traditional timber shear walls in Taiwan by inserting teak and padauk strips into the grooves between wooden planks and beams to increase the embedment strength of beams and the friction between wooden planks and the hardwood strips. A total of 18 full-scale specimens were tested under reversed cyclic loading. The results revealed that the strength and energy dissipation capacities of a wooden shear wall can be significantly increased by inserting teak and padauk strips into the grooves between planks and beams. Furthermore, the simplified calculation method proposed in this study can be used to calculate the strength of both reinforced and unreinforced wooden shear walls with satisfactory agreement.     

毛竹笋,材加工剩余物的饲用价值

对毛竹笋、材加工剩余物作为反刍动物饲料的营养价值进行研究表明，竹笋加工剩余物营养价值较高，可直接或经适当处理后用作饲料，竹材加工剩余物因蛋白质含量低，木质素含量高，直接作为饲料的营养价值不及作物秸秆。由于竹材加工剩余物中含有３／４的碳水化合物，故具有作为反刍动物饲料的潜在价值。对竹材加工剩余物进行氨化处理，可明显提高粗蛋白含量，并使质地变得松软，而竹材加工过程中的高温蒸煮、切削加工和烘干处理等，可破坏其细胞壁，使碎料膨松柔软，降低了粗纤维含量，作为食物纤维素定量的ＮＤＦ、ＡＤＦ和木质素值均有不同程度下降。     

Seismic performance of post and beam timber buildings I: model development and verification

This paper presents a structural model called “PB3D” to perform nonlinear time history analyses of post and beam timber buildings under seismic loads. The model treats the three-dimensional structure as an assembly of roof/floor diaphragms and wall subsystems. The roof/floor diaphragms are modeled by beam elements and diagonal brace elements in order to take into account the in-plane stiffness. The wall system consists of vertical beam elements, for wall posts, as well as nonlinear shear springs to consider the contribution of diagonal wall bracing members or sheathing panels. The hysteretic characteristics of the shear springs are represented by a simplified, mechanics-based model named a “pseudo-nail”. Standard finite element procedure is used to construct the system’s equation of motion, which is solved by Newmark’s integration. The model was verified against shake test results of a three-story post and beam building subjected to strong ground motions scaled to the 1995 Kobe earthquake. Model predictions agreed very well with the test results in terms of base shear forces and inter-story drift responses. This model provides a robust and efficient tool to study the seismic behavior of post and beam timber buildings.     

热带人工用材林研究综述*

在对速生丰产林、速生丰产用材林、工业人工林和人工用材林的概念进行辨析的基础上 ,总结了世界热带人工用材林发展的特点 ,综述了热带人工用材林在政策法规、种苗繁育、造林和经营技术、生产力和轮伐期、立地质量监测和评价、森林病虫害和生物多样性、木材材性和木材工业 7个方面的最新进展 ,最后提出了调整人工用材林发展政策 ;加强生产技术研究和产业带建设 ,提高公众参与程度 ;充分利用市场手段 ,鼓励多元投资主体 ,发展非公有制林业 3条建议以发展我国热带人工用材林产业。