表层压缩技术在杨木实木地板生产中的应用

为扩大意杨木材的应用领域、实现高附加值利用,对意杨木材进行表层压缩处理,再将其制成实木地板.对表层压缩意杨木材的性能,及地板成品漆膜性能的检测结果表明:表面压缩处理后,意杨木材表层密度增加;再经热处理后,表面硬度、弹性模量,弦向尺寸稳定性均有增加,但静曲强度略有降低 ;制成的杨木实木地板的漆膜硬度增加.     

Countermeasure Strategy for China’s Wood Enterprises to Meet Timber Legality Requirements

As the global forest issues and illegal logging have increasingly aroused the concerns of the international community,the US Lacey Act Amendment and the EU Timber Regulation poses requirements for the legality of timber.The paper described the background of timber legality issue,analyzed the specific requirements of the US and the EU for timber legality,and pointed out their negative impacts on China’s wood enterprises.Based on the analyses,the authors came up with the approaches that China’ s wood enterprises could adopt to meet legality requirements,and proposed the specific suggestions on how enterprises respond to the requirements for legality with an eye for the difficulties that they are confronting with.     

Studies on Measurement of Moisture Content by X-ray Scanning Method

In order to explore the feasibility of using X-ray to measure moisture content in the drying process and have a further study on the effect of precision of moisture content when scanning through different grain directions,X-ray scanning method and weighting method were used to measure average moisture content of Cunninghamia lanceolata during hot air drying.The results show that the moisture content values of two methods were very close to one another,the determination coefficients of both were highly correlated with a value over 0.99,and the absolute deviation was below 2%;when scanning along radial direction and longitudinal direction,the precisions of average moisture content were higher than that of the tangential direction,but the deviation can be negligible in the actual measurement;in the practical application,the effect of grain direction on precision of moisture content measurement could not be taken into account when using X-ray to measure the moisture distribution of wood.     

Comparison of Quality of Pulping and Paper-Making between Normal Wood and Tension Wood of Poplar Clone 107(Populus×euramericana‘Neva’) Tree

Both of straight and inclining poplar clone 107 tree were selected for studying materials in this paper.The optimal pulping conditions was established by orthogonal experimental design both for normal wood and tension wood,and the quality of pulping and paper-making between normal wood and tension wood was compared with each other. Finally,potential application for improving paper quality of tension wood through increasing beating revolutions was discussed.The result showed that the optimal cooking condition for normal wood was alkali concentration 15%,the highest temperature 164℃,time at highest temperature 75 min,and for tension wood it was alkali concentration 13%,the highest temperature 160℃,time at highest temperature 40 min.Path coefficient of effect of alkali concentration both on pulp yield and kappa value was significant at different levels.By comparison between average result of normal wood and tension wood in quality of pulping and paper-making,it was found that tension wood had higher pulping yield and lower kappa value than normal wood. Furthermore,for all mechanical properties of paper, normal wood hold higher value than tension wood, and even near two times than tension wood,such as burst index and tensile index.However,difference of tear index was quite narrow.Result of one way ANOVA showed that difference of burst index and tear index between normal wood and tension wood was significant at the 0.001 level,of tear index was significant at the 0.05 level.Based on observation of cross surface of paper,it was assumed that contribution of gelatinous layer to rigidity of single fiber had hampered collapse and compression of fiber during paper formation,which is essential for exerting combination between fibers in paper.So, mechanical properties of tension wood paper were decreased accordingly.However,owing to high cellulose content of gelatinous layer,tension wood was easier to pulping than normal wood.Mechanical properties of tension wood paper could be improved by increasing beating revolutions,     

Analysis on Volatiles Release Behavior of Poplar Wood Powder at Different Temperature by TD-GC/MS and Environmental Protection Evaluation

The volatiles release behavior of poplar powder has been studied by TD-GC/MS online technique at different temperatures.The results show that the proportion of main harmful components was higher than that of beneficial in the volatiles of poplar powder at 40℃ and 90℃,the harmful components was 1.7 times higher than beneficial components. The proportions of main beneficial and harmful components were equivalent at 60℃,while the main beneficial components was 5.42 times higher than that of harmful.Taking poplar wood powder as substrate to prepare wood powder-based composites by high-pressure no-gel molding compaction between the temperature of lignin softening point and wood materials carbonization(about 150-180℃) can present a satisfactory environmental friendliness.     

大花序桉研究现状与发展趋势

大花序桉是优良的实木锯材利用树种,具有重要的经济价值。本文着重论述大花序桉的引种栽培、苗木繁育、木材材性、生理等方面研究进展,提出了当前大花序桉研究和利用中存在的问题,进一步探讨了大花序桉研究的趋势和重点。     

清香木在园林绿化中的应用

清香木为阳性树种,萌发力强,生长缓慢,耐干旱瘠薄,根系发达,抗性较强,是石漠化地区进行绿化造林的先锋树种。嫩叶呈红色,光亮,叶形精致,树形优美,广泛用于园林绿化工程中。     

TDI对聚丙烯/木粉复合材料性能的影响——木粉粒径的影响

采用甲苯-2,4-二异氰酸酯(TDI)改性木粉并制备聚丙烯(PP)/木粉复合材料,研究了不同粒径的改性木粉对PP/木粉复合材料力学性能和加工性能的影响。结果表明,TDI可以改善木塑复合材料力学性能和加工流动性;木粉粒径为120目时,复合材料的综合性能较好,其断面结构较为光滑。     

松材线虫对江西林业和生态环境影响的评估及风险管理

以有害生物风险分析(Pest Risk Analysis,简称PRA)原理为依据,对松材线虫(Bursaphelenchus xylophilus)对江西林业生态环境的影响进行风险评估,认为松材线虫在江西符合检疫性有害生物的地理分布管理标准.江西具备松材线虫生存及蔓延扩散的寄主植物、传播媒介和环境条件.松材线虫随松类植物及产品的调运从境外传入江西后具有蔓延扩散并暴发成灾的潜在风险,对江西林业生产和生态环境及风景名胜区构成了严重威胁.为此,提出了降低松材线虫病风险的管理措施,供江西有关林业部门参考.     

桉树单板化学着色研究

以氯化铁、硫酸铁、硫酸铜、重铬酸钾、重铬酸钠和高锰酸钾等化学试剂为原料进行桉树单板化学着色的药剂配制,获得16种药剂配方。根据着色处理后试件的着色效果和着色渗透深度,筛选出1种适合桉树单板着色的药剂配方处理,代号PBC-1。以PBC-1为处理药剂,采用多因素正交设计分析常压条件下影响桉树单板着色的因素。结果表明:影响桉树单板着色的各因素主次顺序为:药液浓度>处理时间>药液温度>浴比;桉树单板化学着色最佳工艺参数为:药液浓度0.8%,浴比15∶1,药液温度70℃,处理时间10 h;采用所确定的药剂配方和处理工艺,处理后的桉树单板颜色均匀,呈棕褐色,类似柚木色,并且能够很好克服桉树单板表面因节疤所引起的色差问题。