木材染色处理工艺参数对颜色坚牢度的影响

根据可见光分光光度计的工作原理,设计了一种测定染色木材试验颜色坚牢度的方法,并利用这一方法讨论分析了木材染色处理工艺参数对颜色坚牢度的影响。试验以尾×巨桉（Eucalyptus　urophylla×grandis）为试材,以酸性染料为染色剂。试验结果表明在染液配方、染液材积比和染色时间控制不变的条件下,染液温度为颜色坚牢度的第一位影响因子,达到1％显著性水平。在25～80℃的范围内,颜色坚牢度随温度升高而增长,温度越高,增长越快。其次为固色剂浓度,达到5％显著性水平。在0～0.3％的范围内,颜色坚牢度随固色剂浓度增大而增长,低浓度时增长较快。再次为染液pH值,它对颜色坚牢度的影响较小,仅达到10％显著性水平。渗透剂JFC用量对颜色坚牢度的影响不显著,略显负的效应,此有待进一步证实和深入研究。     

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种染料与竹束的结合方式,利用扫描电镜(SEM)观察2种染色竹束的内部结构差异。结果表明:酸性蓝染色竹束的较佳工艺为染色温度90℃、染色时间10 h、染液质量分数0.3%、染液pH为5;活性蓝染色竹束较佳工艺为染色温度70℃、染色时间3 h、染液质量分数0.3%、元明粉质量浓度50 g/L。活性蓝达到最佳染色效果所需的温度和时间均小于酸性蓝,且上染率普遍高于酸性蓝;酸性蓝染色前后色差Δb~*大于活性蓝,这说明经过酸性蓝染色的竹束表观颜色比经活性蓝染色的竹束表观颜色纯正,染色较深。通过FT-IR和SEM分析对比发现,2种染料染色过程中均未产生新的官能团,活性蓝在竹束上的附着力高于酸性蓝。     

低碱活性红染料染色柞木单板的工艺研究

以纺织工业用新型低碱活性红染料为研究对象,采用常规浸渍方法对渗透性较低的柞木单板进行染色,考察染料质量分数、固色剂种类和固色剂用量对染料染色柞木单板上染率和颜色效果的影响。结果显示:染料质量分数、固色剂种类及用量显著影响低碱活性红染料染色柞木单板的上染率和颜色变化,且固色剂用量与染料质量分数协同作用于低碱活性红染料的染色性能;当染料质量分数为1%,固色剂碳酸钠添加量为5 g·L~(-1)时,可以获得理想的上染率和良好的颜色效果。研究结果为建立木材低碱活性染料染色工艺奠定基础。     

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。     

用活性染料对泡桐单板仿红木进行染色的影响因素

采用活性染料对预处理后的泡桐单板进行了仿红木染色研究.结果表明:活性染料对泡桐有较好的易染性,泡桐单板经染色后能达到红木商业用材的自然效果;活性染料染色时,由于上染和固色是分开进行的,固色前染料可以充分进行扩散移染,从而有效避免泡桐单板表芯色差现象;通过控制染色温度、时间以及促染剂和固色剂用量,可得到满意的染色效果.试验得出的染色工艺条件为:温度70~80℃,时间3 h,促染剂元明粉40 g/L,固色剂纯碱20 g/L.     

活性染料的杨木单板染色工艺

采用价格低、色谱全、来源广、渗透性和化学稳定性好的活性染料对杨木单板进行仿黑胡桃染色,通过控制染色温度、时间以及促染剂和固色剂用量,可得到很好的染色效果.试验得出较优染色工艺条件为:温度70～80℃,时间3h,促染剂元明粉40 g/L,固色剂纯碱20 g/L.     

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。     

毛白杨小径材断面浸注法染色因素对上染率的影响

采用断面浸注染色方法,碱性湖蓝BB为染色剂,在单因素试验的基础上,以染料质量分数、染色时间、渗透刑质量分数和pH值为试验因素,用正交试验法对木材上染率进行了测定和分析.结果表明:染料质量分数是第1作用因素,最佳质量分数为0.2%;渗透剂是第2作用因素,质量分数为0.03%时上染率最佳;染色时间是第3因素,最佳染色时间为6天;pH值是第4因素,染液的pH值应控制在4.2～5.2之间.     

人工林杉木的增强-染色复合改性工艺及性能

通过正交试验,考察染料、三聚氰胺改性脲醛树脂、Na_2CO_3质量分数和固化温度对增强-染色复合改性人工林杉木性能的影响。结果表明:树脂质量分数对改性材密度、抗胀率、抗弯强度和模量、抗压强度和色牢度影响显著;染料质量分数对颜色影响显著;Na_2CO_3质量分数对色牢度影响明显,固化温度对抗胀率影响明显。优化工艺为:树脂质量分数30%、染料质量分数1%、Na_2CO_3质量分数0.5%和固化温度100℃,改性材物理力学性能和染色效果良好。     

环保型染料染色技术在杨木单板染色中的应用

针对当前木材染色工业中酸性染料对木材的上染率较低,造成染色废水色度高、处理难度大的现状,选用固色率高、水解低和适合环保要求等优点的含双活性基团的M型活性染料三原色对杨木单板进行染色正交试验,作极差分析确定了速生人工林单板的活性染料染色的较优工艺条件:染色温度为70～80℃,染色时间3 h,元明粉40g.L-1,固色剂纯碱20 g.L-1,其中染色温度对活性染料杨木单板上染率的影响最大,其次是促染剂用量、染色时间和固色剂用量。在较优的工艺参数下对杨木单板进行染色试验,上染率分别为:活性红M—3BE 67.8%、活性黄M—3RE 68.6%、活性蓝M—2GE 58.9%,均大大高于酸性染料对木材的上染率(一般在30%以下)。这种染色方法降低了排放的染色废水中的染料,为速生人工林杨木的节能、环保染色提供了一条新的途径。     

Growth of Phlebiopsis gigantea in wood of seven conifer species

Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.     

Growth of Mixed Birch-Coniferous Stands in Relation to Pure Coniferous Stands at Similar Sites in South-eastern Norway

Mean age, mean and top heights and yield were studied in 20 mixed stands of birch ( Betula pubescens Ehrh. and B. pendula Roth) and Picea abies (L.) Karst. and nine mixed stands of birch and Pinus sylvestris L. in south-eastern Norway. Each mixed stand and the adjacent pure coniferous stand (control) were growing under the same site conditions and had not been commercially thinned. There were no significant differences in mean age at breast height or in top heights between birch and conifers in the mixed stands, while mean height was significantly higher for birch than for spruce. A growth index was calculated based on total volume and age at breast height. For the spruce sites the growth in young mixed stands (birch < 17 m) was superior to that of pure spruce, while the difference was insignificant in older stands. The growth index correlated positively with the ratio between generatively and vegetatively regenerated birch trees, and negatively with the age of the oldest species in the mixture and with site quality. For the pine sites there was no significant difference in the growth index between mixed birch-pine and pure pine stands. A mixture effect of birch on the volume yield of spruce or pine could not be demonstrated.     

Defoliation by the Needle-shortening Pine Gall Midge,Thecodiplosis brachyntera,on Pines in Central Sweden

An outbreak of the needle-shortening pine gall midge, Thecodiplosis brachyntera , occurred on Scots pine, Pinus sylvestris (L.) and lodgepole pine, P. contorta (Dougl.) in central Sweden during 1995-1998. The larval feeding of T. brachyntera kills current-year needles and heavy infestation causes severe defoliation. A pattern of fluctuating defoliation among years and sites was found on both pine species. Defoliation was evenly distributed in the crown of P. sylvestris during years of high as well as low infestation; apical whorls had as much defoliation as basal whorls. In P. contorta , however, there was a tendency for defoliation to be concentrated on branches in the most apical whorls. Growth ring increments on P. sylvestris with high levels of defoliation (71%) did not differ from trees with moderate levels (26%) of defoliation. Shoot lengths were significantly shorter, however, on heavily infested trees the year after defoliation.     

Boron in forest trees and forest ecosystems

This review critically examines the role of boron (B) in forests in view of recent findings on B nutrition and the continuing occurrence of B deficiency. Many perceptions about the role of B in plants and its uptake and mobility have been altered since the last review on B in forest trees in 1990. Now there is evidence for a fundamental role of B in the formation of the pectic structure in primary cell walls in plants, and further roles in membrane function are being explored. In plants, channel-mediated B uptake, active B uptake and B uptake by mycorrhizas have been shown, B transporters have been identified, and B retranslocation has been shown. We explore these findings and their consequences on forest trees and on ecosystems that they dominate. Particular emphasis is placed on B retranslocation and B in mycorrhizal symbiosis, given their importance in trees.     

Development of Pinus sylvestris Main Stems Following Three Different Precommercial Thinning Methods in a Mixed Stand

Reducing competition by point cleaning may be an attractive alternative to conventional precommercial thinning in forestry. In this study, survival and development of main stems of Scots pine (Pinus sylvestris L.) following point cleaning were examined in a mixed stand of mainly Scots pine and birch (Betula pendula Roth and Betula pubescens Ehrh.) in northern Sweden. Treatments studied were: no precommercial thinning, conventional precommercial thinning, point cleaning of all secondary stems, and point cleaning of only the secondary stems that were higher than the main stem, within a radius of 0.8 m from the main stem, respectively. A randomised complete block design with three replicates was used. Measurements taken 13 growing seasons after these treatments showed that conventional precommercial thinning was the best treatment for retaining Scots pines as main stems. However, conventional precommercial thinning resulted in the poorest timber quality of the remaining Scots pines in terms of stem taper, thickest branch diameter and relative live crown height. In conclusion, point cleaning has to be followed by a complementary cleaning operation if the objective is to retain Scots pines as main stems in such mixed stands.     

Survival and Growth of Picea abies Regeneration after Shelterwood Removal with Single- and Double-grip Harvester Systems

Three stands in Sweden were followed for 7 yrs to study the survival and growth of Norway spruce [Picea abies (L.) Karst.] regeneration after shelterwood removal with single- and double-grip harvester systems. The height of all seedlings within circular plots was recorded before and after final cutting. The tallest seedling and one randomly selected seedling on each circular plot were permanently marked and their annual height growth was measured each year during the period 1993-1999. No significant differences between single- and double-grip harvester systems were found with respect to their effects on regeneration density, survival or annual height growth. The annual height growth of the individual seedlings after shelterwood removal was significantly correlated with seedling height before shelterwood removal. Significant differences were found in annual height growth between seedlings with high and low vitality. Logging damage did not affect the annual height growth. Several practical conclusions were drawn. First, the choice of harvester system does not affect seedling height growth or survival after shelterwood removal. Secondly, the removal of a 200 m³ shelterwood with 200 stems ha^-1 does not seem to constitute a serious problem for seedling survival and growth. Finally, estimated vitality and seedling height both seem to be fairly good predictors of postrelease survival and growth.     

Tree planting for dryland salinity control in Australia

Dryland salinity is emerging as a major form of land and water degradation in southern Australia, particularly in Western Australia, South Australia and Victoria, and to a lesser extent in New South Wales, Tasmania and Queensland.Tree planting, in combination with other vegetation treatments, is regarded as a leading solution to dryland salinity. Research has now shown that planting trees can significantly lower groundwater tables, and thereby reverse the causal process of salinisation. Substantial progress has been made towards answering the basic questions of which species to grow, how to plant, where to plant, at what density and configuration to plant, and how much area to plant. The economic potential for commercial tree planting has given impetus to partial reforestation in higher rainfall (> 600 mm yr^–1) areas. Even so, serious constraints are apparent, relating primarily to cost, uncertainty and attitude. The future should bring increasing community input and control, technical refinement and gradual adoption, provided all aspects of the issue are well researched, relevant information is well communicated and programmes are well administered. Some specific requirements for future research are identified in this review.     

Effect of Cuttings on the Scenic Beauty of a Tree Stand

The opinions of 207 respondents on the visual effects of seven different cutting types were asked using a nine-point verbal scale ranging from ''worsens very much'' to ''improves very much''. Other estimates were obtained by letting the same respondents evaluate photographs of stands which had been treated with different cuttings. The direct questions gave results quite similar to the evaluations of photographs for all but young respondents, indicating that most respondents were able to imagine the effect of the treatment correctly. The results based on the evaluation of photographs indicated that the effect of regenerative cuttings is negative while the impact of thinnings is positive. After a few years of cutting the stand is already regarded as clearly more pleasant than immediately after the cutting. Natural regeneration with seed trees seems to be a way to avoid the very negative immediate impact of clear-felling, especially in the case of Scots pine. Women, young, urban people and those who do not own forest or have work related to forests tended to experience thinnings less positively and saw regenerative cuttings as more harmful than the other test groups did.     

Pinus contorta growth in northern Sweden as affected by soil scarification

The aim of this study was to quantify the effects of different soil scarification methods on tree growth. Soil scarification influenced stem volume and stem biomass yield of lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) in a 17-year-old field trial in boreal Sweden. Soil scarification (disc trenching, mounding and ploughing) resulted in an average stem volume yield of 3.1 and 34.2 m³ ha^–1 on the poor and intermediate sites, respectively, while corresponding values for no soil scarification were 0.9 and 16.7 m³ ha^–1. In comparison to no scarification, ploughing increased volume yields by 500% on the poor site and by 200% on the intermediate sites. The ranking according to stem volume yield was ploughing > disc trenching = mounding no soil scarification. Averaged over the two sites, the mean annual increment of stem biomass was 219% and 145% higher (in d.w., 0.26 kg and 0.34 kg per sample tree) after ploughing compared with no soil scarification, for the average and dominant sample trees, respectively. Although not significant, the increased growth rate after soil scarification decreased the average stem basic wood density of the sample trees with 1.6% and 5.3%, at the poor and intermediate sites, respectively. In conclusion, soil scarification significantly increased the 17-year stem volume yield compared with no scarification. The results also indicate that the difference in stem biomass yield between ploughing and the other methods, especially no soil scarification, will increase even more in the near future.