木材断口分形的初步研究

木材是一种天然的多孔性生物高分子材料,结构复杂且变异性大,所以木材断裂表面定量分析的难度很高,对于木材内部裂纹产生、发展的研究一直没有大的突破.在木材断裂力学的研究中,国内外科学家运用传统的断裂试验方法研究居多,但普遍结论是规律不明显或找不到规律(费本华,1999).木材研究者们一直在寻找一种定量描述木材断裂表面形态的新指标,并希望在此基础上预测木材强度和了解木材断裂机制(Schmitt et al.,1996;Qin et al.,1999).     

汽车车厢底板用竹木复合板的研制

采用马尾松作芯板、竹片作表板、酚醛树脂作胶粘剂，制造汽车车厢底板用竹木复合板。在确定的涂胶量、热压温度、热压时间条件下，研究了不同的热压压力与竹木复合板性能的关系，得出了适宜的热压工艺条件。研究结果表明，竹木复合板的物理力学性能达到林业行业标准ＬＹ１０５５—９１规定的指标值，为充分、合理、经济、有效地利用竹木资源提供了依据     

Experiences of a Forest Owners’ Cooperative in using FSC forest certification as an environmental strategy

Yusuhara Forest Owners’ Cooperative (YFOC) in Kochi Prefecture in Japan received its forest management certification from the Forest Stewardship Council (FSC) in 2000. YFOC is recognised as the resource manager of its members’ forests, and they were the first organisation to gain such certification in Japan. With the continuous efforts of selling FSC certified wood in the domestic housing construction market, YFOC has substantially increased their timber sales in recent years. It is a noteworthy event in Japanese small-scale forestry, which has been struggling with declining economic performance for many years. This paper analyses the detail of forestry activities and changes which occurred in YFOC after certification by FSC. An interesting effect of increasing economic performance is found to have come from an unexpected direction. It is concluded that the FSC certification system is a possible tool to revitalise Japanese small-scale forestry as well as obtain favourable environmental outcomes.     

云南哀牢山自然保护区南华片区项目建设必要性分析

对哀牢山国家级自然保护区南华片区的生物多样性、经营现状和经营管理进行评价,对项目建设必要性分析结果:项目建设有利于该保护区的整体效应;有利于对珍稀植物物种和生态系统的保护;有利于对候鸟迁徙通道的保护;有利于社会经济的可持续发展;是加强科研和宣教工作的需要。最后阐述了项目建设的主要内容。     

菊叶薯蓣组织培养及快速繁殖

菊叶薯蓣组织培养以大田栽培苗地上部分幼嫩茎段作外植体。芽诱导培养基为MS+6-BA0.5～2.0mg·L-1+NAA0.1mg·L-1,继代增殖培养基为MS+6-BA1.0mg·L-1+NAA0.1 mg·L-1,生根培养基1/2MS+NAA0.5mg·L-1,每个过程均培养30d,每节段增殖2～3倍,生根率为85%以上。移栽基质为土壤∶珍珠岩(1∶3),遮光率为80%,保持较高湿度,每7d喷施1/2MS无机盐,1个月后成活率可达60%～80%。     

纤维增强定向成型材强化结构设计计算

纤维增强定向成型材是国内外人造板研究发展的一项创新,是一种可替代天然林木的复合材料.本文利用复合材料强度设计的方法,对其强化结构进行了设计计算,建立了纤维增强定向成型材强化结构模型.     

Chemical characterization of smoke from the production process of wood-plastic composites

The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust (Fraxinus mandschurica Rupr.) and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290°C during 8 min (the conditions were similar to those employed on an industrial scale). The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry (GC-MS). The analytical r...     

径向竹帘复合板的研究——制板工艺

通过对径向竹帘复合板的制板工艺、物理力学性能、经济效益的分析表明 :径向竹帘复合板具有物理力学性能高、板面质量好、竹材利用率高、胶粘剂用量少、热压周期短、产量高、能耗低等优点 ,是一种竹材资源全方位、高效加工利用的新途径。     

基于细胞数字特征的板材材种识别技术

木材识别是合理利用木材最基本的前提。为了解决人工鉴定失误率高的问题,本文提出基于细胞数学描述理论的板材识别方法,采用木材端面细胞的显微数字图像,利用板材材种的数学仿真技术、图像处理技术、数据库管理和系统辨识方法,提取细胞轮廓形态和尺寸等参数建立基准细胞和材种识别数字化参数库。减少传统的依赖图像像素特征识别比较方法的不确定性,创新材种识别的数字化理论体系,推动板材材种识别的实用化。     

对住宅建设的一点看法

本文着重从几个方面论述住宅建设今后的发展方向。使住宅总体规划合理,经济适用,住宅建设与环境协调,达到可持续发展原则的绿色住宅和生态住宅区。