浸渍胶膜纸浸胶量对饰面中纤板表面性能的影响

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。     

复合地板无醛饰面材料加工工艺研究

为实现复合地板的无醛饰面,采用水性丙烯酸树脂对花梨木、樟子松薄木和原纸进行浸渍,研究丙烯酸树脂浓度对黏度、浸胶量的影响及浸渍时间对丙烯酸树脂浸胶量的影响。结果表明:随着水性丙烯酸树脂浓度的降低,其黏度也随之降低,当树脂浓度降至84%,其黏度呈现明显下降的趋势,随后趋于相对稳定;结合水性丙烯酸树脂浓度对浸胶量和挥发物含量的影响,优选浸渍纸的树脂浓度为68%,浸渍花梨木、樟子松薄木的树脂浓度为80%;实验室优选薄木与原纸的浸渍时间均为1 min。     

废浸渍纸粉末用作胶合板脲醛树脂胶填料的研究

为降低脲醛树脂胶调胶成本,及有效利用三聚氰胺树脂浸渍纸废料,将浸渍纸边回收、粉碎,以替代工业面粉用作脲醛树脂胶填料,制备胶合板.结果表明:浸渍纸粉末用量为树脂质量的10％～15％时,试板的胶合强度最高；甲醛释放量随浸渍纸粉末比例的增加而降低.浸渍纸粉末作为胶合板用脲醛树脂胶的填料具有可行性.     

利用国产装饰原纸生产三聚氰胺浸渍胶膜纸的工艺研究

国产原纸湿强度低 ,p H值低且不均衡 ,纤维分布不均匀 ,灰分含量也低。采用以有机溶剂代替浸渍用树脂中的部分水、施加脱膜剂、加大浸渍纸的浸胶量等措施 ,解决了上述问题对生产的影响 ,生产出符合标准要求的三聚氰胺浸渍胶膜纸     

蔗糖改性浸渍薄木用MF树脂性能研究

为改善三聚氰胺甲醛(MF)树脂贮存稳定性短及胶层脆性大等问题,利用蔗糖对浸渍薄木用MF树脂进行改性,研究改性剂蔗糖添加量与反应介质pH值对浸渍用MF树脂性能的影响,并利用傅里叶变换红外光谱仪对改性后蔗糖-三聚氰胺甲醛(SMF)树脂进行结构表征。结果表明:改性剂蔗糖的加入可以增强MF树脂的拉伸韧性及贮存稳定性,可使浸渍后的薄木顺纹拉伸强度提升到38.6 MPa;当蔗糖添加量为20%(与三聚氰胺质量比)、反应介质pH=8.0时,树脂贮存稳定性可达17 d,且浸渍薄木饰面后的三层杨木地板表面各项理化性能,均满足GB/T 18102—2007《浸渍纸层压木质地板》标准要求。     

三聚氰胺浸渍薄木饰面水泥刨花板的研究

通过三聚氰胺浸渍薄木对水泥刨花板进行饰面,可提高水泥刨花板的表面质量。经过前期的单因素实验,以饰面质量为依据,得出适于水泥刨花板饰面用三聚氰胺浸渍薄木的主要指标:浸胶量为120%~150%,预固化度为40%~60%。通过正交分析试验,产品各种性能指标符合GB/T15101—2006《装饰单板贴面人造板》和GB/T 15102—2006《浸渍胶膜纸饰面人造板》标准,并得出浸渍薄木饰面水泥刨花板的最优工艺为:热压压力为1.2MPa,热压温度为150℃,热压时间为360s。     

三聚氰胺浸渍纸边角废料制造复合刨花板工艺研究

三聚氰胺浸渍纸是人造板行业用量最大的饰面材料之一。为拓展三聚氰胺浸渍纸边角废料的利用途径,以杂木刨花和回收的原态浸渍纸边角废料为原料制备复合刨花板。采用正交试验方案,探究了浸渍纸边角废料纸添加量、施胶量和热压参数等因素对板材物理力学性能的影响。结果表明:在三聚氰胺浸渍纸边角废料添加量为20%、脲醛树脂胶黏剂(UF)施胶量13%、热压温度190℃和热压时间9 min工艺条件下,制备的复合刨花板物理力学性能符合GB 4897—2015中P2型刨花板指标要求。     

低压短周期胶膜纸在MDF饰面生产中的应用与检验

1饰面用浸渍胶膜纸及其用途饰面用浸债胶膜纸（简称胶膜纸，标记SJ）是指出专用纸浸渍氨基树脂（主要是三聚氰胺树脂）或酚醛树脂，并干燥到一定固化程度的一种浸渍纸。用这种股股纸经热压可直接粘合成覆贴在人造板表面进行装饰加工，它不仅能遮盖住人造板表面的部分缺陷，美化外观，提高人造板的使用价值，同时还赋于人造板表面具有耐磨性、耐水蒸汽性、耐化学药品污染腐蚀性、耐于热性、耐香烟灼烧及尺寸稳定性、表由平滑光洁易清洗等优良性能，可扩大人造板的使用领域。经过这种装饰的人造板现已广泛应用于厨房家具、办公用品以及室内装…     

纳米复合浸渍处理对饰面人造板甲醛控释的影响

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。     

单层浸渍纸贴面葵花秆刨花板的研究

本文论述了葵花秆刨花板的生产工艺、产品性能，分析了单层浸渍纸贴面用基材板的性能，并与国家标准进行了比较，填补了几项指标要求。研究中对国产刨花板设备及其生产工艺进行了调整，生产出了符合单层浸渍纸贴面板性能要求的基材板，同时研制了改性三聚氰胺树脂胶、改性脲醛树脂胶，制定了单层浸渍纸贴面工艺，贴面板各项性能达到国家标准。     

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.