拟赤杨育苗试验简报

黎川岩泉自然保护区有小片零星野生拟赤杨,为发展本地树种资源,我们进行了拟赤杨大田育苗试验。拟赤杨〔Alniphyllum fortunei(Hemsl.)Perk.〕又名“萝卜树”、“冬瓜木”,属野茉莉科。多生于海拔1500m以下山区阔叶林中,喜光喜湿润温暖气候,天然更新良好,形成次生林常与枫香、翅荚木、香槐等     

拟赤杨等4种阔叶木BCTMP制浆性能研究

对拟赤杨、火力楠、米槠、山乌桕等 4种阔叶树进行BCTMP制浆、打浆强度分析、漂白工艺研究、与硫酸盐木浆配抄强度比较及黑液分析 ,结果表明 ,拟赤杨、火力楠、米槠、山乌桕等 4种阔叶树具有较好的制浆适应性     

拟赤杨等4川阔叶木BCTMP制浆性能研究

对拟赤杨、火力楠、米槠、山乌桕等４种阔叶树进行ＢＣＴＭＰ制浆、打浆强度分析、漂白工艺研究、与硫酸盐水浆配抄强度比较及黑液分析，结果表明，拟赤杨、火力楠、米槠、山乌桕等４种阔叶树具有较好的制浆适应性。     

拟赤杨的栽培技术

拟赤杨是一种生长快，干形直，用途广的优良速生阔叶树种。通过对拟赤杨的采种、育苗、造林和天然林调查，了解和掌握了该树种的生态特征和生长规律，阐述了该树种的营林主要技术措施。。     

速生丰产林栽培技术之一拟赤杨栽培技术

拟赤杨别名赤杨叶，安息香科，是速生、丰产、优质的落叶阔叶树种，生长迅速，枯枝落叶量多。拟赤杨和杉木等混交具有良好的效果。在人工针叶林比例日益增大的情况下，推广拟赤杨造林具有重要的意义。拟赤杨为落叶乔木，高达２５m。树干通直，具纵条纹，不开裂，树皮暗灰色，其上多灰白色块斑。其木材是家具、造纸及制作火柴杆的优良用材。拟赤杨分布于长江以南的福建、江西、湖南、湖北、四川、云南、贵州等地，垂直分布可达海拔１０００m以上，常见于海拔１２００m以下的阔叶林中。要求温暖湿润的气候条件，喜生于温暖避风处和湿润肥沃、…     

制备竹麻粘胶短纤维的方法

目前,传统的粘胶纤维是以针叶木制造而成,由于该原料短缺和制浆技术的不断创新,一些阔叶木、棉短绒等也被用于粘胶浆粕的生产中,但以针叶木和阔叶木为原料会涉及到树木采伐,从而影响生态环境;短棉绒资     

马尾松人工林皆伐1年后新增天然阔叶幼树初报

福建永安市31a生马尾松人工林皆伐迹地封育1年后,新增天然阔叶幼树树种多达71种、株数密度高达64 547株/hm~2。其中天然阔叶乔木树种38种、重要值30.64%、株数密度12 200株/hm~2,常绿与落叶天然阔叶乔木树种分别为22种和16种,这是非常宝贵的天然阔叶乔木树种资源,是该区域人工林植被管理的重要基础。这些阔叶乔木树种中有不少珍贵的或高价值的用材树种,如红楠、木荷、青冈栎、米槠、红锥、刨花润楠、闽楠、檫树、泡桐、南酸枣和拟赤杨等。     

北江中上游生态公益林树种选择与综合评价分析

在广东乐昌龙山林场进行山乌桕等43个乡土阔叶树种山地造林对比试验,4年生结果显示,43个树种间的造林成活率、树高、胸径、冠幅生长量均存在极显著差异,表明北江流域山地造林成功的技术关键之一是树种选择.43种乡土阔叶树种的高生长与胸径(地径)生长均表现出极显著的正相关(P＜0.000 1).根据各树种的造林成活率与生长量的综合表现,山乌桕、黎蒴、冬桃杜英、枫香、山杜英、拟赤杨、网脉山龙眼、石栎、荷木、杨梅、拐枣在北江流域山地造林表现较优,可作为当地营造水土保持林、水源涵养林等生态公益林的首选树种.     

10种常绿阔叶树种理化性质的研究

常绿阔叶树种是森林的主要植物种类,具有含水率高的特点。选择石栎Lithocarpus glaper、拟赤杨Alniphyllum tortunei、冬青Ilex chinensis、樟树Cinnamomum philippinense、木荷Schima superba、罗浮栲Castanopsis fabri、山杜英Elaeocarpus decipiens、甜槠Castanopsis eyrei、苦槠Castanopsis sclerophylla、油茶Camellia oleifera 10种常绿阔叶树种,采集不同树种的树叶、树枝和树皮,烘干粉碎后在室内进行理化性质的测定分析,以不同树种器官的含水率、热值、燃点、木质素、粗纤维、粗灰分、粗脂肪7个指标作为评价因素,对10个树种的抗火性进行聚类分析,结果表明:抗火性强的是冬青;抗火性较强的有3种,由强到弱依次是油茶、山杜英、拟赤杨;抗火性一般的有2种,由强到弱依次是苦槠、石栎;抗火性较弱的有4种,由强到弱依次是木荷、樟树、甜槠、罗浮栲。研究结果能为防火树种的筛选提供理论依据。     

马尾松与几种阔叶树种混交的初步研究

通过对马尾松与几种阔叶树种混交6 a试验表明:马尾松与枫香、火力楠、拟赤杨、光皮桦、观光木、鹅掌楸、山杜英、凹叶厚朴混交后,促进了林木的生长,混交林树高、胸径生长量都大于马尾松纯林和阔叶树纯林。     

European hardwoods versus Eucalyptus globulus as a raw material for pulping

The importance of eucalypt as a raw material for pulping is steadily growing. Eucalyptus globulus was compared with European hardwood species using two alkaline pulping processes, kraft and alkaline sulfite, anthraquinone pulping (ASA), which is a recently developed modified alkaline sulfite process. All cooks were performed to similar kappa numbers. Poplar cooks resulted in the highest yields followed by eucalypt and birch which were on the same level. Yield of beech pulps was definitely lower. ASA pulps show a moderate higher yield due to the less alkaline pH-profile of the cooking liquor. This yield advantage was maintained and even enhanced after TCF-bleaching. The bleaching response of all pulps was excellent. The birch pulps had the highest tensile strength followed by the poplar and beech pulps. Surprisingly eucalypt pulps had the lowest tensile strength. But this was compensated by the very good tear index of eucalypt pulps. The runnability factor, as an index for the overall strength potential, was on the same level for all pulps. Due to the higher hemicellulose content of the ASA pulps their tensile strengths were higher, but tear strengths lower compared to the kraft pulps. The different morphology of the hardwoods investigated resulted in different volumes and light scattering coefficients of the corresponding pulps. Dedicated to Prof. Dr. Dr. h. c. mult.Walter Liese on the occasion of his 80th birthday.     

Mode I fracture and acoustic emission of softwood and hardwood

 The Mode I fracture behaviour of two softwoods (spruce and pine) and three hardwoods (alder, oak and ash) was studied in the RL crack propagation system using the splitting test in combination with monitoring acoustic emission (AE) activity. Test parameters measured included notch tensile strength, specific fracture energy, characteristic length and AE cumulative counts, AE amplitudes as well as parameters characterizing the frequency spectra of the emitted acoustic emission events. The notch tensile strength was found to correlate with density. The specific fracture energy and characteristic length showed the different crack propagation process between the softwoods and hardwoods. The softwoods fractured in a more ductile way and the hardwoods showed a more linear elastic behaviour. This finding was supported by the AE measurements showing much less cumulative counts for the hardwoods indicating that less microcracks were formed and that processes like fiber bridging were not so effective. Differences in the frequency domain of the AE signals between softwoods and hardwoods could not be detected. Received 13 January 1999     

6种热带、亚热带阔叶树种苗木生态化学计量特征

为了解不同珍贵树种在生长中对营养元素的需求及利用特点,以土沉香(Aquilaria sinensis)、樟树(Cinnamomum camphora)、降香黄檀(Dalbergia odorifera)、格木(Erythrophleum fordii)、闽楠(Phoebe bournei)及檀香(Santalum album)等6种国家珍贵树种为研究对象,探讨苗木体内碳、氮、磷元素的化学计量特征.结果表明,树种间碳氮磷含量及C∶N∶P计量特征均存在显著差异(P＜0.05).叶片C∶N比值(24.12 ～44.76)及C∶P比值(208.82～573.34)普遍高于全球平均水平(分别为22.5和232),但与亚热带鼎湖山树种含量平均水平相当(分别为25.5和561);而叶片N∶P比值(4.77～15.00)与全球平均水平相当(比值为12.7),但低于鼎湖山森林平均水平(比值为22),表明苗木在培育过程中很可能存在N、P元素供给不足的情况,今后应注意加强施肥以促进苗木的生长.     

林业“三剩物”的开发利用现状和前景概述

目前国内"三剩物"(采伐剩余物、造材剩余物和加工剩余物)以作为人造板和制浆造纸的原料、制备化学品以及作为直接和间接燃料的形式被利用.国际上林业剩余物能源的研究开发主要集中于气化(使有机物转化成可燃气体)、液化(利用生物发酵或酸水解技术制取乙醇和通过热解等技术转化成液化油)和固化(林业剩余物能源固化成型技术).未来林业"三剩物"的开发利用将集中在:作为木材的替代资源的开发利用;以木材"三剩物"和次小薪材为原料生产加工综合利用产品;林业"三剩物"高品质生物质能源产品的开发.     

Torsional-shear stress of wood at various temperatures

Summary The maximum torsional-shear stress of 5 softwoods and 4 hardwoods were tested in the radial and tangential planes. These tests were carried out in glycerin which was preheated to different temperatures between 22°C and 150°C, inclusively. The dense hardwoods possess 2.4 times higher shear stress than softwoods at 22°C. However, at elevated temperatures, the same degree of shear stress reduction (77 %) is obtained for hardwoods and softwoods in both radial and tangential failure. Thus, the reduction in shear stress is independent of physical and structural wood variables.     

Influence of accessory substances,wood density and interlocked grain on the compressive properties of hardwoods

Wood samples of nine tropical hardwoods from Peru and sugar maple wood from Quebec were selected to perform moisture sorption tests associated with parallel-to-grain and tangential compression tests using a multiple step procedure at 25°C. Cold-water and hot-water extractives, sequential cyclohexane (CYC), acetone (ACE) and methanol (MET) extracts, ash content (ASH), wood density and interlocked grain (IG) were evaluated on matched samples too. Wood density corrected for the accessory substances was by far the major factor positively affecting the compressive properties of tropical hardwoods. The total amount of accessory substances is required in order to establish better relationships between physico–mechanical properties and density of tropical hardwoods. For a given wood density, the ultimate stress in parallel-to-grain compression was higher in tropical hardwoods than in temperate hardwoods. However, the compliance coefficients for both types of woods were quite similar. Sequential extraction with organic solvents was the most suitable method for evaluating the effect of extractives on compressive properties of tropical hardwoods. The CYC and ACE fractions did not contribute to variation in these mechanical properties. The substances dissolved in MET affected positively the compliance coefficient s ₁₁ in parallel-to-grain compression and negatively the compliance coefficient s ₃₃ in tangential compression. The IG decreased the compliance coefficient s ₁₁ but also decreased the ultimate stress in parallel-to-grain compression. Finally, variations in compressive properties that were due to changes in equilibrium moisture content (EMC) were clearly influenced by wood density; denser woods were more sensitive to changes in EMC than lighter woods.     

世界木材制浆造纸工业技术发展趋势

林业是制浆造纸工业的基础，纸和纸板是高效益的林产品之一。随着科学技术的进步，制浆造纸工业已成为高技术工业。本文介绍了制浆造纸的原料问题和４种主要的制浆方法，并对制浆造纸工业技术的发展趋势进行了预测。     

A review of the utilisation of hardwoods for LVL

This review on the use of hardwoods for the production of LVL revealed that a large number of research studies have been carried out, particularly in North America and three Asian countries (Japan, Malaysia and China). However, the studies have been restricted to species of low to medium density, i.e. 290 to 693 kg/m³. Two major potential uses of hardwood LVL have been investigated in these studies: domestic and industrial structures, and various furniture components. The production of structural LVL in North America and Asia was based predominantly on low density hardwoods. A study currently carried out in Europe aims at using medium density hardwoods for structural LVL. The LVL used for furniture components was produced from medium density hardwoods. No work has been undertaken outside Australia on the use of high density species for LVL. In Australia, studies undertaken on the production of LVL and hardwood plywood from eucalypts revealed that there were significant problems in gluing the dense raw material which often had a high level of extractives. Peeling low quality, small diameter eucalypt logs also created problems when the traditional plywood processing techniques were used. Received 7 July 1997     

我国竹材加工工业的现状及发展

改革开放以来,我国在竹材工业性开发利用方面取得了很大成绩、竹材加工扩要产品有以下４类：（１）竹材人造板;（２）竹工艺品;（３）竹工艺品;（４）竹将造纸。本文着重介绍这四类产品的生产现状及开发前景。