响应面法优化杨木单板的染色工艺

采用酸性染料对速生杨木单板染色,考察染液质量分数、染色时间和染色温度对单板色差值的影响.采用响应面法(RSM)建立二次回归模型,并对染色工艺进行优化.结果表明:在染液质量分数0.52%、染色时间4.2 h、染色温度72 ℃时,能够获得比较理想的染色效果,杨木单板的色差值为62.54 NBS.     

酸性蓝和活性蓝染色竹束工艺与性能比较

以竹束为研究对象,分别采用酸性蓝和活性蓝为染料.设定酸性蓝的染色时间和温度、染液质量分数和pH,以及活性蓝的染色时间和温度、染液质量分数和促染剂(元明粉)质量浓度为自变量,以上染率和色差Δb?、ΔE?为评价指标,研究2种染料的最佳染色工艺,对比2种染料的染色工艺与染色效果;并采用傅里叶变换红外光谱(FT?IR)分析2种...     

杨木单板染色工艺对颜色坚牢度的影响

以酸性大红GR、酸性黑ATT和酸性橙Ⅱ为染色试剂,选取染色温度、染液pH值、固色剂和均染剂的质量分数为工艺参数,进行意杨单板染色试验和颜色坚牢度测定。结果表明:在本试验条件下,温度为80℃、pH6.5时,颜色坚牢度最大;固色剂质量分数0.1%时可达到较好的固色效果;均染剂质量分数为1.0%时颜色坚牢度较好。     

染色工艺对桉木单板上染率的影响探究

为改善桉树单板材色,用酸性橙为染色试剂对漂白弦切桉木单板进行染色,选取NaCl质量分数、酸性助剂质量分数、染料质量分数、染色温度和染色时间为工艺参数,进行桉木单板染色试验和上染率测定。结果表明:在本试验条件下,染料最佳质量分数为0.01%、NaCl最佳质量分数为0.2%、酸性助剂最佳质量分数为0.1%、最佳时间为4h、最佳染色温度的为70℃,此时,桉木单板的上染率最好。     

预处理对尾巨桉单板染色性能的影响

采用乙醇处理、碱处理和热水处理三种方式对尾巨桉单板进行预处理,由正交试验确定最佳染色工艺并在最佳染色工艺条件下对预处理单板进行染色,然后对染色单板的着色性能、耐光色牢度及耐水色牢度进行测定。结果表明：正交试验确立的最佳染色工艺为染液温度70℃、染色处理时间45 m in和酸性蓝浓度0.2%,其中染液温度是影响染色效果的最主要因素;三种预处理方法能够提高尾巨桉单板的渗透性并对着色性能影响不大,同时会使染色处理材的耐光性小幅下降;三种预处理方式对染色材的耐水色牢度有较好的促进作用,其中热水处理最好,乙醇处理次之,而碱处理最差。     

活性艳蓝X-BR上染白枫单板的性能研究

研究了活性艳蓝X-BR上染白枫单板的影响因素和最佳染色工艺,采用7因素4水平正交染色试验,考察了染色温度、染液质量分数、促染剂用量、染色时间、固色剂用量、固色时间、体积比7个因素对上染率和表面色差的影响。采用直观分析和方差分析得出了影响上染率和表面色差的主要因素,并采用扫描电镜(SEM)观察染料分子在木材内的分布情况,以及X射线能谱分析(EDXA)染料分子的特征元素在木材中的含量。研究结果表明:染料质量分数和染色温度对上染率和表面色差影响较大。上染率最佳工艺方案为:温度60~65℃,质量分数0.5%,促染剂用量50 g/L,染色时间3.0 h,固色剂用量15 g/L,固色时间75 min,体积比1∶15。表面色差最佳工艺方案为:温度50~55℃,质量分数3%,促染剂用量40 g/L,染色时间3.0 h,固色剂用量15 g/L,固色时间75 min,体积比1∶40。SEM和EDXA结果表明染料分子团聚在木射线周围和分散在导管内,且染料分子的特征元素含量增加。     

I-214杨染色单板光变色规律的研究

以染料弱酸深蓝5R和活性艳红X-3B染色的I-214杨素材和漂白板为试材,选用氙光作照射光源,考察不同染料、不同工艺条件下染色单板在110 h光照过程中试材表面材色指数,即明度指数(L*),色度指数(a*与b*)和变色度(△E* ab)的变化.结果表明:染色单板在110 h氙光照射过程中变色明显,b*值提高显著;△E* ab在光照初期大,后期平缓直到不变;同一品种染料,高浓度染液中染色单板比低浓度染液的光照变色大,浸染时间长短对染色单板光照变色影响不明显,先漂白再染色的单板材色均匀,光照变色平缓;不同品种染料的染色单板光照变色规律有差异.     

荷木单板的漂白与染色工艺

试验研究了荷木单板漂白工艺及染色时间，染液浓度，染液温度等染色工艺参数对漂白单板染色效果的影响，结果表明：当染色时间在5h左右，染液浓度控制在0.5%-0.6%，染液温度保持在70-80℃时，单板内部染色的，染色效果好，具有良好的装饰效果。     

泡桐单板染色因素对上染率的影响

对泡桐单板染料上染率的影响因素进行研究,试验材料为0.5mm漂白泡桐刨切单板,染料为酸性大红,结果表明,NaCl对上染率作用显著,随NaCl浓度增加,上染率明显增加,但超过1%时反而下降,染色温度对上染率影响极显著,随温度的升高,上染率增加,90℃时达到最大值;随染色时间的延长,上染率逐步增加,直到染料在木材中的扩散和吸附达到平衡,0.5mm泡桐单板在90℃染色3h,可达到要求的染色效果;染料浓度不同,上染率也不同,1%浓度的上染率最大;随着染液材积比的增加,染料吸附量也增加,适宜的染液材积比是15：1;乙酸对泡桐单板上染率有促进作用,最佳浓度1.5%。     

马占相思边材染色渗透深度影响因素初探

通过多因素正交试验,对影响马占相思边材染色渗透深度的因素进行初步研究.结果表明,在常温、常压和染液质量浓度一致的条件下,影响马占相思边材染色渗透深度的主次因素分别为渗透剂用量、染色温度、染液pH值和染色时间;在本试验条件下,马占相思边材染色达到最大渗透深度的最佳方案为:渗透剂用量8%,染液温度90℃,染液pH值为4,染色时间180min.     

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.