机械应力式人造板质量在线无损检测技术的研发和应用

静弯曲弹性模量(MOE)是结构用板材(如大片刨花板、定向刨花板、结构胶合板、单板层积材等)最为重要的力学指标,而静弯曲强度(MOR)则是几乎所有人造板(如胶合板、刨花板、中密度纤维板等)的最为重要的力学指标.     

我国人造板的进出口形势和2011年的预测

随着人造板应用范围的不断扩大,国内外对人造板的需求量不断增加,使我国的各种人造板的流通量很大.由于近几年来,我国的胶合板、中密度纤维板不但产量不断增加,而且质量也在不断提高,所以进口量不断减少,但是,由于高质量的胶合板、中密度纤维板和刨花板还不能满足市场的需求,因此,我国每年仍然要进口一定数量高质量板以满足家具和装修的用材.     

全国人造板标准一览

一、现行的我国人造板标准1纤维板难燃中密度纤维板GB/T18958-2003中密度纤维板GB/T11718-1999薄型硬质纤维板LY/T1205-1997浮雕纤维板LY/T1204-1997硬质木纤维瓦楞板LY/T1203-1997硬质纤维板GB/T12626-1990地板基材用纤维板LY/T1611-20032刨花板刨花板GB/T4897.1~4897.7-2003石膏刨花板LY/T1598-2002定向刨花板LY/T1580-2000模压刨花制品(家具类)GB/T15105-1994船用贴面刨花板LY/T1057-19913胶合板胶合板GB/T9846.1~9846.8-2004集装箱底板用胶合板GB/T19536-2004竹编胶合板GB/T13123-2003汽车车厢底板用竹材胶合板LY/T…     

当今短周期贴面技术

一、概述 人造板改善表面质量和素板再加工最常用的方法是用薄膜贴面,贴面板在家具和地板产品等方面得到广泛应用.世界范围对家具贴面板材和强化地板的需求仍旧是大的,而且有广阔的发展前景.几乎所有机器生产的人造板,如:刨花板、中密度纤维板、高密度纤维板和THDF板均适于贴面.     

日本人造板供应量创6年新高

2006年日本人造板供应急剧扩大到1126万m^3，比2005年增加4％，创自2000年以来的新高。胶合板是日本主要的人造板产品，占整个人造板产量的72．3％；其次为刨花板，占15．2％；中密度纤维板占8．1％；阻燃板占3．6％。日本胶合板供应量的约60％、中密度纤维板的52％、刨花板约27％（其中一半是定向刨花板）和阻燃板约0.7％靠进口。     

我国人造板标准情况(续)

(截止 2 0 0 2年 12月 )二、即将发布实施的人造板标准·船用贴面刨花板·胶合板·刨花板·人造板板材尺寸测量长宽厚度的测定·石膏刨花板·人造板板材尺寸测量垂直度及不直度的测定·竹编胶合板·地板用纤维板·竹篾积成胶合板·不饱和聚酯树脂装饰胶合板·汽车车厢底板用竹材胶合板·集装箱底板用胶合板·旋切单板·装修、门、窗用绿之可板 (挤压木塑复合材 )·混凝土模板用酚醛胶膜纸贴面胶合板·人造板甲醛释放量检测用 1m3气候箱装置·阻燃中密度纤维板·人造板甲醛释放量检测用 4 0 L干燥器装置三、正在制、修订的人造板标准·硬质…     

基于YOLOv5的人造板板材种类识别

废弃人造板板材回收再利用之前进行横截面统一类型,对于提高板材的综合利用率具有重要作用。综合利用机器视觉和深度学习方法,选取刨花板、纤维板和胶合板3种人造板板材作为研究对象,通过扫描仪采集板材横截面纹理,并对大量的纹理数据进行训练,学习图像深层次特征,在图像识别和分类上取得良好的效果。采集刨花板、纤维板、胶合板、塑料板、金属板和泡沫板6种人造板板材横截面图像共900张,其中刨花板234张,纤维板232张,胶合板234张,塑料板、金属板和泡沫板共200张作为负样本;搭建基于YOLOv5的深度学习人造板板材种类识别框架。试验结果表明,基于YOLOv5的人造板板材种类识别框架可以有效识别人造板板材的类型,刨花板和胶合板的识别准确率为100%,纤维板的识别准确率为99.2%;该方法检测速度快、精度高,针对人造板板材数据集具有良好的鲁棒性和泛化能力,解决了传统方法检测效率低和人工干预的成本问题,达到资源循环利用的高度智能化水平,充分满足回收再生产的应用需求。     

欧洲人造板工业结构的变化和技术新进展

北欧人造板工业呈现出截然不同的发展趋势.芬兰的桦木胶合板工业仍处于稳定的状态.随着该地区唯一的中密度纤维板厂及若干纤维板和刨花板厂的关闭,人造板的生产能力集中到少数大厂.英国还处在发展刨花板阶段.比利时是欧洲第三大刨花板市场,正加紧发展高技术的刨花板饰面.西德以刨花板质量好、产量高而著称.自1988年它的两个中密度纤维板厂投产后就要改变它进口中密度纤维板的局面.奥地利、瑞士都仍在加强刨花板工业.意大利的刨花板工业自80年代中期以来一直处于困境,尽管如此.又有一条新的连续热压生     

加拿大人造板工业概况

加拿大是一个林业和木材加工工业都很发达的国家。该文简要介绍了有加拿大人造板工业（包括胶合板、定向结构板、刨花板和中密度纤维板）的概况，以及最新的人造板生产技术。     

碎料成型压模的若干问题

碎料成型压模的若干问题陆肖宝（南京林业大学南京２１００３７）随着人造板生产技术的不断发展，它的产品已不再局限于平面型的产品，一些曲面型的成型产品也早已面世。现在人造板的模压生产已广泛用于胶合板、刨花板、中密度纤维板及碎料成型塑料。产品有：扬谷板、椅背...     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.