竹木混合纤维制备工艺研究

竹木混合纤维的制备直接关系到竹木复合中密度纤维板生 产工艺路线的选择。此项研究在比较分析竹、木纤维形态差异的基础上,考察了竹木片混合 磨浆的可行性和影响纤维质量的主要工艺参数。结果表明：在适宜的工艺条件下,可以采用 竹木片混合磨浆工艺制备用于中密度纤维板生产的竹木混合纤维;在实验室条件下,竹木片 混合比和磨浆时间对纤维质量影响显著。     

浅谈近自然林业

从历史的角度提出了近自然林业的建设问题，阐明了近自然林业的理论基础及核心内容，并对未来的发展道路进行了展望。     

中国26种豆科木材导管附物纹孔的电镜观察和研究

本文对我国豆科植物的3亚科、19属、26种木材导管的附物纹孔进行了扫描电镜观察,除3属4种木材的导管无附物纹孔外,其余均有。附物纹孔的有无及其形态、分布特征是区分豆科各属、种的一个重要标志。此外,14种木材切片用5％次氯酸钠溶液处理后,大部分附物减小,以至消失。又对其中一种木材的超薄切片进行透射电镜研究表明,附物和次生壁的电子密度不同,说明两者的化学成分不同。还对附物的形成、生理功能、与瘤状物的关系进行了讨论。     

溶剂体系对聚乙二醇浸渍杨木尺寸稳定性的影响

为探究溶剂体系对聚乙二醇浸渍处理后杨木尺寸稳定性的影响,采用分子量1 000、2 000和4 000的聚乙二醇分别与丙酮、乙醇、水进行复配,然后浸渍杨木,考察了密度、增重率和体积膨胀率的变化。结果表明,丙酮作为溶剂时,浸渍后木材密度增幅最大,增重率显著高于乙醇与水的体系,常温30 d后尺寸变化最小。乙醇与水作为溶剂时,3种分子量的聚乙二醇浸渍木材密度和增重率相差不大,但乙醇溶剂在保持尺寸稳定性上明显优于水溶剂。丙酮作为溶剂时,易增加聚乙二醇在木材中的渗透性,提升增重率和木材密度,能有效控制体积膨胀率。说明聚乙二醇浸渍木材的性质与溶剂类型有关。     

村落风水林休闲游憩开发

在对村落风水林的休闲游憩价值分析的基础上,提出对风水林进行景观生态改造、配套乡村自然休闲设施以及组织林下空间休闲活动等村落风水林休闲游憩开发建议。     

Chemical characteristics of woods from several Chilean native forest species and their relationship with nanomechanical cell properties

The objective of this research was to study the chemical and nanomechanical characteristics of native woods grown in southern Chile region. The species analysed were Drimys winteri, Laureliopsis philippiana, Aextoxicon puctatum, Nothofagus alpina, Nothofagus dombeyi, Laurelia sempervirens, Austrocedrus chilensis and Fitzroya cupressoides. The samples were collected from the regions of Biobío (37° S, 73° W), Araucanía (37° S, 71° W) and Los Lagos (40° S, 73° W). Chemical analysis reported that glucan content of native woods was between 39% and 44% and lignin content between 28% and 35%. The nanomechanical properties analysed in the secondary cell wall (S2 layer) and middle lamella (ML) were elastic modulus (E), hardness (H) and ductility ratio (E/H). Values for E_S2 were between 12.0 and 15.4 GPa and for E_ML between 4.3 and 6.6 GPa. Hardness values were similar in ML and S2 (≈0.3 GPa). The compilation of results showed high correlations between E_S2 and carbohydrate content (r = 0.80), between E_S2 and hemicellulose content (r = 0.89), and between H_S2 and lignin content (r = 0.88).     

东北林区64种木材腐朽菌木材分解能力的研究

采用常规重量分析法，分别测定了64种木材腐朽菌对红松、青杨、白桦木块的木材分解能力，测定了受菌侵染46d后木材样品的重量损失百分率和木块的颜色变化。结果表明这些木腐菌的木材分解能力显著不同。采自长白山林区的厚黑层孔菌Nigrofomes castaneus(Imaz.)Teng是木材分解能力最强的褐腐菌、它分别引起白桦、青杨、红松木材样品的重量损失百分率为64．9％、52．2％和16．9％。白干酪菌（Tytomyces albidus)，灵芝（Ganoderma lucidum)、冬拟多孔菌（Polyporellus brumalis)、三色革裥菌（Lenzites tricolor)、棱孔菌（Favolus alveolaris)、朱红密孔菌（Pycnoporus cinnabarinus)、彩绒革盖菌（Coriolus versicolor)等是几种木材分解能力强和较强的白腐菌。     

Effects of extraneous substances,wood density and interlocked grain on fiber saturation point of hardwoods

Abstract

Samples of nine tropical hardwoods from Peru and sugar maple wood from Quebec were selected for moisture sorption and swelling tests at 25°C. These tests evaluated the fiber saturation point (FSP) by two methods: following adsorption over distilled water, and from the volumetric swelling intersection point. Cold-water and hot-water extractives, sequential cyclohexane, acetone and methanol extracts, ash content, wood density and interlocked grain were also determined on matched samples. The results indicated that adsorption tests over distilled water were not applicable for determining FSP in all wood species. Condensation of water vapor apparently occurred, even though temperature during adsorption was controlled to the nearest 0.01°C. The volumetric swelling intersection point method was judged more appropriate. FSP ranged from 15 to 25% for tropical hardwoods and was 30% for sugar maple wood. FSP was negatively correlated with wood density, acetone extracted fraction, interlocked grain and ash content. These parameters each exerted similar effects on variability in FSP.     

毛环竹笋用林生物量结构调查分析

通过对毛环竹林分、单株生物量及其结构特征调查分析,结果表明:毛环竹林分生物量在一定范围内随着密度的提高而增大,在密度为10800～12900株·hm-2时生物量最大,地上部分可达到50t·hm-2以上,地下部分可达到30t·hm-2以上。各器官生物量分配为:地上部分生物量秆>枝>叶,其比例大致是6∶3∶2或2∶1∶1;地上部分>地下部分,其比例变化幅度在1 183～1 784之间。毛环竹单株生物量与胸径、竹高呈正相关,在生产实践中可用模型W=aDbHc进行估测,其精度达95%以上。     

发展速生树种定向培育工业用材林的研究

对我省30a以下人工更新的大青杨、香杨、红松人工林的生长量进行实际调查，结果表明，27a生时胸径为7．5cm。对落叶松进行定向培育，在皆伐迹地二次人工造林，实行短轮伐作业，生长效果显著。最佳造林密度为3300株／hm^2。