木材颜色调控方法

木材调色可以改善木材表面的装饰性能,使木材获得更高的价值.可通过物理或化学方式将染料或颜料与木材结合在一起;可以使用光或热改变木材的颜色;也可以使用微生物调控木材的颜色;还可以通过智能仿生的方法调控木材的颜色.本文总结了常见的术材颜色调控方法,新型的微生物染色方法和仿生智能的木材颜色调控方法,并分析了各方法的特点.新兴...     

木、竹、藤材的变色防治

对木材变色的机理、类型、成分和影响因素, 木材变色的预防和消除以及生物防治等研究的最新成果进行了概括总结, 综合论述了木材、竹材和藤材的变色防治研究现状, 得出以下几点结论:(1)低毒或无毒、高效、多功能的防变色剂的研制开发仍是木材工业变色防治研究的重要研究方向。(2)开展色变脱除, 恢复已变色材原有颜色和价值方面的研究很有必要。(3)以菌治菌的生物防治, 污染小, 成本低, 应加强其理论研究和实践应用。(4)通过热处理或光辐射等手段, 诱导木、竹、藤材变色, 进行调色处理, 将成为新的研究方向。(5)与木材相比, 竹材、藤材变色的研究落后, 尤其是藤材变色, 应得到进一步加强。     

杨木和樟子松单板的光变色规律

以杨木和樟子松单板为试材,利用氙光衰减仪进行光辐射试验,分析其光变色规律,并进行耐光性能评价.结果表明:木材受光辐射易发生变色,主要表现为明     

白桦木材的变色类型及变色前后化学成分分析

通过化学方法、材面色差分析法、扫描电镜观察和化学成分分析,研究了白桦木材的蓝变和黄变,探讨了变色的原因及主要类型。研究结果表明:白桦蓝变材的变色是由变色菌侵蚀木材引起的,变色深入木材内部。木材薄壁细胞腔内充满了大量的变色菌丝体,菌丝体本身的颜色及其分泌的色素是木材变色的原因。蓝变材部分半纤维素发生降解,其各项抽提物含量比正常材高;而黄变材是由于自然环境变化引起的创伤性木材变色,存在于木材局部区域,其部分导管和少量木纤维细胞被胶状物所填充,内含物增加,木材三大组分没有明显变化。     

白桦木材侵染菌侵染材的化学分析

白桦木材在自然和人工干燥过程中易受真菌类微生物的侵染产生色变,在一定程度上降低了白桦木材的加工利用价值。本文针对白桦木材侵染菌侵染试材的化学成分变化进行分析,以期为白桦木材生物变色防治提供参考。首先对白桦木材侵染菌进行分离、纯化与鉴定,确定侵染白桦试材的侵染菌的基本类型,然后进行白桦试材接菌,最后对白桦侵染菌侵染木材的化学成分进行测定。结果表明,与未侵染素材相比,侵染菌侵染试材中苯醇抽提物含量、1%NaOH抽出物含量、热水抽出物含量和多戊糖含量均较高,而纤维素及木素含量较低。这表明侵染菌在适宜的条件下会侵蚀白桦木材细胞壁组织,造成纤维素和木素等主要成分含量的降低,导致木材组分的破坏。同时,侵染菌的存在会造成白桦木材抽提物组分中的显色及助色物质的含量变化,以致木材产生不同程度的变色。     

木材诱发变色研究现状与趋势

介绍了木材诱发变色的变色机理, 从光变色和热变色2个方面分析了木材变色是内因在外因的诱导下发生的自身化学成份的变化, 探讨了材色的评价方法、诱发变色及变色的防护方法, 并指出木材诱发变色的研究方向。     

泡桐材变色类型的确定及变色真菌的鉴定

对泡桐材变色类型的研究表明,泡桐材变色存在着真菌变色。同时从新伐的泡桐木材中分离出两种真菌,经鉴定是链格孢菌和一种根霉菌,这两种真菌可引发泡桐木材变色。     

木材用透明涂料耐光性能的研究

以木材涂饰用水性双组分聚氨酯和丙烯酸清漆制备的游离膜为试材,利用氙光衰减仪进行辐射试验,研究游离膜的材色变化规律,并进行耐光性能评价.结果表明:聚氨酯和丙烯酸漆膜受光辐射均会发生变色,并且聚氨酯漆膜的光变色度更甚,主要表现在聚氨酯漆膜的色品指数显著增大,说明聚氨酯漆膜易发生黄化.     

木材变色机理研究进展

木材资源的多元化利用符合可持续发展国家战略方针。但木材在使用过程中会由于内部或外界因素产生变色,造成木材性能劣化,直接影响木材及其制品的质量。因此,研究木材变色机理以缓解木材缺陷具有现实意义。目前已有大量研究集中于木材随环境因子的变色规律,但仍存在环境条件考虑单一、化学结构变化规律不明确等问题。文中将变色木材的主体分为活立木和木材加工产品2类,分别对其变色的内因和外因进行总结;分析目前研究中存在的问题和未来研究方向,以期通过总结已知环境因子对木材变色的作用,服务于各因子协同作用下木材变色结果的研究,为减少木材变色缺陷和定向调控木材颜色提供研究思路,并为提高木材综合性能、拓展木材及其制品的应用范围提供参考。     

科尔沁沙地引种樟子松木材变色原因浅析

樟子松是我国三北地区主要造林树种,具有速生、树干通直、蓄积量大等特点。但其采伐后,木材经过一段时间的储存,芯部会出现"蓝变"。这种变化是评价木材质量的一个重要指标,影响木材加工后产品的质量。文章研究确定了樟子松木材变色属于微生物变色类型,分析了樟子松在自然条件的变色规律,为找到控制这种变色的办法提供了理论依据。     

Review on Wood Discoloration and its Control

Wood color is an important factor to determine wood impression. It is also the most vivid and active factor in furniture and interior decoration design. It is an important index to evaluate wood commercial value, and strongly influences wood sale competition power. Wood discoloration is the change of normal wood color. Plywood, veneer, furniture and decorative wood products have some limits on wood discoloration, and export products have also strict limit on it. Discoloring of biomass wood is…     

Induction of discolored wood in Scots pine (Pinus sylvestris)

Induction of discolored wood in Scots pine (Pinus sylvestris L.) trees by treatment with ethylene, carbon dioxide, nitrogen (hypoxia) or wounding from early April to late September was investigated. All treatments induced formation of discolored wood upward and downward from the drill hole. The amount of discolored wood formed above the drill hole depended on the treatment in the following order: ethylene > carbon dioxide = nitrogen > wounding; and below the drill hole in the order: ethylene > carbon dioxide = nitrogen = wounding. Based on chemical analyses (HPLC/UV, GS/MS, LC/MS and 1H-NMR), discolored wood induced by wounding or treatment with ethylene or carbon dioxide showed compositional similarities to natural heartwood, whereas discolored wood induced by nitrogen treatment showed fewer similarities to natural heartwood. The results suggest that ethylene is an important factor controlling heartwood formation, although wounding and internal concentrations of carbon dioxide may also play a role.     

BACTERIAL SWOLLEN STEM CANKER ON POPLAR:THE DISEASE AND ITS CAUSES

The bacterial swollen stem canker of poplar is prevalent in planted poplars ofnortheast China.Serious damage occurs in the form of necrosis,putridity,cankers,swollen stemsand discolored wood of trunks and branches of young and mature trees.Tests of allergic reaction,pathogenicity,culture characteristic,Gram stain and anaerobic culture revealed that the pathogen isErwinia sp.Its occurrence depends mainly on the predisposing factors of the disease among whichthe susceptibility of poplars is the most important one.The disease becomes widespread in associa-tion with low-lying and high-humidity terrain,frost injury,node wounds,insect damage,and prun-ing and other mechanical wounds.Harmful factors promote the disease.     

Damage to residual stands from thinning with short-span tower yarders: Re-examination of wounds after five years

The current status of wounds on residual trees was investigated and compared with the wound status from five years ago when the stands were thinned and logged. Wound status was defined according to the four levels of severity based on appearance. Several damaged trees were cut for inspection of the wounded areas. Most wounds of a lighter severity level had already healed by occlusion and were no longer evident. Wounds reflecting heavy damage but had healed, were smaller in the horizontal dimension, or width, than those not yet healed. Slight wounds, but with a current status reflecting persistent damage were smaller in the vertical dimension, or length. An inspection of wound sections revealed the development of discoloration in the wood. Only the slight wounds that healed early had no or small discolored areas. The width of discolored areas of wounds in which cambium was still exposed was greater than the original width of the wound. In conclusion, wound width rather than length significantly affects healing or occlusion of wounds.     

木材变色病对木材工业的影响

由于木材变色已给木材工业带来较大的经济损失，因此，有效地保护木材，提高它的利用率就变得更加重要。本文对由长喙壳和其他真菌引起的木材变色，变色机理，为害，对木材性质的影响，以及我国主要木材变色病的研究进行了概述。     

Induced discoloration of buerger maple during drying process

Buerger maple (Liquidambarformosana Hance) is a kind of wood that is easily discolored. This paper tries to obtain satisfactory color and a broad prospect in the utilization of buerger maple by induced discoloration. The authors analyze the mechanism of induced discoloration of buerger maple based on the analysis of visual physical parameter, the infrared spectrum (IRS) and the scanning electron microscope (SEM) under different drying conditions. The result shows that it is feasible to induce discoloration during the drying process. The wood color tends to be red and fuscous during inducing discoloration of buerger maple.The induced discoloration mechanism is: 1) the high temperature and humidity accelerates the oxidation reaction of polyphenol,leuco-fancy pigment and tannin, which changes the wood color to red; 2) the hydroxy (-OH) is oxidized and the carbonyl (-C=0),carboxyl (-COOH), ester and ketone groups form during the high temperature steaming, which results in wood piece discoloration.     

我国木材科学研究的现状与发展趋势

从木材科学研究的内容出发,分析了我国木材科学研究的现状,并对我国木材科学研究的发展趋势做了深入的探讨,指出今后我国木材科学研究将向着多学科、更先进的研究方向发展。     

美国木材与纤维复合材料研究现状

对美国木材工业及纤维复合材料方面的研究及发展现状进行了论述, 重点介绍木材工业、木结构材料、木基复合材料、纤维复合材料、木材化学利用和木材生物质能源等领域的研究现状和发展动态, 并针对我国木材利用现状提出开展木材资源系统基础及应用研究、加快环境友好型天然纤维复合材料研发和加强木材化学及能源利用研究的建议。     

木材真空干燥特点及国内研究现状

阐述了木材真空干燥的特点和国内研究现状,真空干燥可满足木材高品质、高效率、低成本的干燥目标,对推进行业节能减排工作、解决难干材和改性处理材干燥问题、提高干燥品质等均具有重要意义。对真空干燥木材的机理、研究进展、可能的研究方向进行评述,以期促进木材真空干燥科研工作和生产实践的共同发展。