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1.
采用1 m3气候箱法测试2种浸渍胶膜纸饰面人造板甲醛释放规律以及不同处理条件对板材甲醛释放浓度的影响。结果表明,热压工艺、基材结构可能是影响甲醛释放周期的关键因素,2种饰面人造板的平衡周期基本相同;封边处理可有效降低甲醛含量得释放;温度和相对湿度与板材甲醛释放量呈正相关,空气交换率与板材甲醛释放量呈负相关。  相似文献   

2.
通过对比试验,分析浸渍胶膜纸的不同浸胶量对饰面中密度纤维板耐冷热循环、耐磨、耐香烟灼烧、耐龟裂、耐污染腐蚀、耐水蒸气等表面性能的影响。结果表明,胶膜纸的浸胶量控制在120%~140%之间,饰面中纤板表面的各项性能指标均达到GB/T 15102-2006《浸渍胶膜纸饰面人造板》的要求。  相似文献   

3.
人造板甲醛释放量的对比测试   总被引:2,自引:0,他引:2  
吴萍  周萍  胡艳玲 《林产工业》2002,29(5):8-10
分别采用穿孔萃取法和干燥器法测试了刨花板、高密度纤维板、浸渍胶膜纸饰面刨花板和浸渍纸层压木地板的甲醛释放量。在测试中发现,用穿孔萃取法和干燥器法测甲醛释放量,两者所测得数据之间存在着一定的换算关系。  相似文献   

4.
以甲醛释放量为E_0级的细木工板为基材,杨木单板为缓冲层,甲醛释放量≤1.5mg/L的A级浸渍胶膜纸为饰面材,制作浸渍胶膜纸饰面细木工板(生态板),分析浸渍胶膜纸与生态板甲醛释放量的相关性。结果表明:生产试验条件制备的生态板,其含水率、表面胶合强度、浸渍剥离、耐冷热循环、耐光色牢度、表面耐龟裂等指标均符合Q/TBB 0022-2016《浸渍胶膜纸饰面胶合板》要求;只有浸渍胶膜纸甲醛释放量≤0.7mg/L时,制备生态板的甲醛释放量≤0.5mg/L,达到E_0级。  相似文献   

5.
1 概述 板式家具是以各种贴面的人造板作为板式部件,借助五金联接件、圆棒榫等结合方式组装而成的家具.板式部件是贴面人造板基材和封边材料组成的复合结构材料.常用的基材有中密度纤维板、刨花板、多层胶合板、细木工拼板和单板层积材等人造板;贴面材料主要有三大类:木质、纸质和塑料.木质贴面材料包括灭然薄木、人造薄术和单板等;纸质贴面材料有印刷装饰纸、合成树脂浸渍纸和装饰板;塑料贴面材料有聚氯乙烯(PVC)薄膜和聚丙烯薄膜.  相似文献   

6.
结合浸渍胶膜纸饰面细木工板(生态板的一种)的特点和装饰材料阻燃功能需求,以生产常用的MUF树脂和阻燃剂调配生态板专用阻燃胶黏剂,通过试验探究胶黏剂和专用阻燃剂的配比、阻燃胶的涂布量因素对浸渍胶膜纸饰面细木工板性能的影响。结果表明:采用两次涂胶工艺,浸渍胶膜纸饰面细木工板的浸渍剥离、表面胶合强度达到GB/T 34722—2017《浸渍胶膜纸饰面胶合板和细木工板》要求,甲醛释放量符合Q/YFL 0030—2018《木质板材及其制品中甲醛释放限量》要求,阻燃性能满足GB/T 8624—2012《建筑材料及制品燃烧性能分级》B1-C等级要求。  相似文献   

7.
甲醛是室内常见污染气体,主要源于板式家具和人造板装饰材料中,长期接触会对人体健康产生极大威胁。以人造板饰面用薄木、微薄木、三聚氰胺浸渍原纸为对象,通过浸渍掺杂纳米二氧化钛(Ti O2)的掺杂三聚氰胺树脂胶黏剂,探索3种浸渍处理材料对饰面人造板的甲醛控释能力。研究结果表明,纳米Ti O2的加入,能够不同程度的降低薄木、微薄木、浸渍纸3种材料饰面人造板的甲醛释放。随着纳米Ti O2添加量的增加,饰面人造板的甲醛释放量呈逐步下降的趋势。当纳米Ti O2添加量达到2%质量分数时,微薄木饰面人造板甲醛释放量最低,仅为未处理板材的32.9%。傅里叶变换红外光谱(FT-IR)与差示扫描量热法(DSC)分析结果表明,纳米Ti O2掺杂处理三聚氰胺树脂胶黏剂未生成新物质,不会影响热压过程中胶黏剂在饰面材料表面的固化,但对材料表面的润湿性有一定影响。  相似文献   

8.
综合信息     
全国人造板标准概况之二(截至2004年12月底) 1 已报批的我国人造板标准 ·不饱和聚酯树脂装饰胶合板 ·刨切单板 ·木材胶粘剂及其树脂检验方法 ·木材工业胶粘剂用脲醛、酚醛、三聚氰胺甲醛树脂 ·人造板甲醛释放量检测用1立方米气候箱装置 ·竹材地板 ·集成材地板 ·单板层积材 ·木塑复合材(挤出成型)2 已审查、待报批的我国人造板标准 ·饰面用浸渍胶膜纸 ·装饰单板贴面人造板 ·浸渍胶膜纸饰面人造板 ·人造板甲醛释放量检测用40L干燥器装置 ·船用贴面刨花板 ·硬质纤维板 ·细木工板 ·刨切车厢胶合板 ·软木…  相似文献   

9.
1 概述 强化木地板为俗称,其学名为浸渍纸层压木质地板.它是以浸渍热固性氨基树脂的耐磨纸和木纹纸及平衡纸分别铺装在刨花板、中密度纤维板、高密度纤维板等人造板基材表面及背面,经热压、分片和加工企口而成的地板.  相似文献   

10.
1 浸渍纸层压木质地板及其标准1.1 浸渍纸层压木质地板简介 浸渍纸层压木质地板(以下简称强化木地板)取材于速生树种、采伐剩余物等,经先进的高科技手段加工制作而成,是当代新科技的产物。强化木地板是以中密度纤维板、高密度纤维板或特殊形态的优质刨花板为基材,并用特种耐磨材料作为覆面材料制成的一种板材。其结构分为四层:表层为耐磨层,采用三氧化二铝或碳化硅覆盖在装饰纸上,耐磨层采用高科技手段,使其具有惊人的耐磨强度;第二层为装饰层,也就是电脑仿真制作的印刷纸,用现代高科技滚筒印花,可显示出各种名贵实木的纹…  相似文献   

11.

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.  相似文献   

12.

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.  相似文献   

13.

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.  相似文献   

14.

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.  相似文献   

15.
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。  相似文献   

16.

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.  相似文献   

17.
18.

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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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