Alternative wood treatment with blends of linseed oil,alcohols and pyrolysis oil

Linseed oil is a common wood treatment agent,which is often blended with naphthenic oil during its application.In this study,we developed new types of linseed oil blends,where the naphthenic oil was substituted with alcohols and pyrolysis oil.As miscibility tests revealed,linseed oil can be blended indefinitely with primary alcohols containing three carbon atoms or more.In addition,kinetic stability of three-component-mixtures was found,which comprised linseed oil,alcohol and pyrolysis oil.The developed blends were further tested for their viscosity and rate of solvent evaporation.At last,trial impregnations of wood were done to test this new treatment agent.The uptake of treatment oil and the effect on water repellency varied,and substituting white spirit with propanol and pyrolysis oil showed potential.The latter were miscible with 50%(wt)linseed oil at concentrations of 37.5%1-or 2-propanol and 12.5%pyrolysis oil.Compared with the reference case,treatment with this agent markedly decreased the water-uptake of the wood.Our study hence attributes great potential to the newly developed linseed oil blends,which may introduce additional product characteristics and generate value to byproducts via pyrolysis.

THE EFFECT OF HEAT TREATMENT ON DIFFERENT SPECIES WOOD COLOUR

In this paper, the heat tratment of wood samples of 8 tree species with different colour were made at different temperature and time. Using SC-1 Model colorimeter, the colorimetric parameter was measured at quantitative measuring for treatment fore-and-after wood sampIes color. The effect of heat treatment conditions on wood color was analyzed. The results indicated: the temperature and time of heat treatment affected on big extent for wood samples color, in which the heat temperature was more evident than others. The luminance index of wood color parameter was more sensitive to treatment condition, which it reduced with temperature and time increasing, this kind of variation tendency was the same as all wood samples, but the variations extent was more different among the different wood species. After heat treatment the wood color hue and saturation variation direction were different for different wood species.This phenomenon had the relation to the migration and volatilization of color extract in heating process, or the rapid oxidation of lignin and some chemical element in high temperature.

Monosaccharide Recovery from Peat and Peatified Wood by Ultrasonication Pretreatment and Hydrothermal Treatment

Peat and peatified wood are significant carbohydrate resources in tropical rainforests. The carbohydrates of cellulose and hemicellulose are important sources of monosaccharides for both vital activities and industrial applications, such as furan production of furfural and hydroxymethyl furfural. Hydrothermal treatment at 200°C and ultrasonic irradiation pretreatment were used to recover monosaccharides from the abovementioned resources. The monosaccharide recovery from peat was shown to be higher than that from peatified wood. The conversion to organic acids is considered to proceed rapidly because acids are always detected with monosaccharides. This conversion is outstripped by the organic acid-to-gas reaction for treatment times longer than 20 min. The monosaccharide recovery from peatified wood was improved by the ultrasonication pretreatment. It is considered that ultrasonic irradiation broke down lignin blockages, enabling water molecules to access the carbohydrates more easily in the subsequent hydrothermal treatment.

Structural Change of Wood Molecules and Chemorheological Behaviors during Chemical Treatment

It is very important to clarify the relationship of changes of molecular combinations in wood cell walls and the chemical rheological behavior during various chemical reagent treatments, for it would be helpful to develop new wood modification technologies and to enrich the theory of chemical rheology of wood. Based on previous investigations on the chemorheological properties of wood by chemical treatments and the applied methods in chemical rheology of wool fibers, this paper proposes the study of various additional reagents to wood saturated in water for long periods of time in order to investigate the chemical rheology of wood, which can provide information about the character of combinations between wood molecules and the structural changes of molecules and further put forward the idea of modifying wood in a decrystallized state.

Impacts of freezing and thermal treatments on dimensional and mechanical properties of wood flour-HDPE composite

Wood plastic composite （WPC） of wood flour （WF）, high density polyethylene （HDPE）, maleic anhydride-grafted polyethylene （MAPE） and lubricant was prepared by extrusion, and then exposed to different temperatures to evaluate the effects of freezing and thermal treatment on its dimensional and mechanical properties. At elevated temperatures, WPC expanded rapidly initially, and then contracted slowly until reaching an equilibrium state. Treatment at 52°C and relative humidity of 50% for 16 days improved the mechanical properties of WPC： flexure, tensile strength, and izod unnotched impact strength increased by 8%, 10% and 15%, respectively. Wide-angle X-ray diffraction （XRD） tests showed that the degree of crystalization of HDPE in WPC declined with increasing treatment temperature.

Wood灯检查在白癜风治疗期间不同复色模式观察研究中的应用

目的:通过观察Wood灯下白癜风患者治疗过程中皮损的复色模式,探究不同复色模式的相关影响因素,分析评估不同复色模式间的疗效差异。方法:收集选取2021年8月-2022年8月笔者医院就诊的90例(170块),采集患者基本信息及病情相关指标。治疗后,观察Wood灯下皮损复色模式,将复色模式与收集指标进行统计分析,筛选出差异有统计学意义的指标后,采用Logistic回归分析阳性指标与复色模式的相关性。并将Wood灯下观察的皮损面积作为疗效判定标准,分析对比不同复色模式间的疗效差异。结果:One-way ANOVA分析、χ^(2)检验显示白癜风疾病分期、皮损部位、治疗方式与皮损复色模式有关(P<0.05)。Logistic回归分析显示:治疗方式与复色模式存在相关性(P<0.05)。不同复色模式达到有效复色面积的时间比较,差异有统计学意义(H=8.04,P<0.05)。结论:通过观察Wood灯下白癜风患者治疗过程中皮损的复色模式发现,治疗方式可能是白癜风皮损复色模式的决定因素;不同复色模式之间的复色速度存在差异,可作为临床医师调整治疗方案的参考依据。

Effect of high temperature heat treatment on pH value of Masson Pine wood

Heat-treated wood has good dimensional stability,corrosion resistance and visual quality,but it is prone to mold,which limits its application.Based on the pH value of heat-treated wood,this study examines the factors affecting the pathogenesis causing heat-treated wood mold.Normally,the pH value of the heat-treated wood is between 4.38 and 5.10,which is suitable for the growth of mold.However,the pH of the heat-treated copper-containing material is between 6.63 and 7.12,which deviates the treated wood from the comfortable growth conditions for the mold,thereby reducing the occurrence of mold.

PCDD/F Dioxin Profile of Treated Pinus pinaster Wood

This work describes the treatment of Pinus pinaster wood with four different industrial wood preservatives (two anti-bluing or fungicide and two fungicide/pesticide) and the detection and quantification of the dioxin contamination profile in the wood shavings. The samples were collected from poultry liters during three contamination incidents of poultry meat. Two methods used were, both nonpressure: one by immersing the wood samples in the preservative solution and the other by impregnation of the preservative solution into the wood, with vacuum. It was concluded that there is no difference in terms of contamination profile, caused by the different industrial wood treatment preservative products in study. A clear correlation between the commercial products used in wood treatment and the contamination profile of wood shavings that have been used as bedding material in poultry production was detected.

Same Recovery Level of Compressed Chinese Fir Wood Can Be Obtained Through Different Heating Fixation Pathways

The recovery of compression set (RS) of wood after dry heating or steam treatment mainly depends on the temperature and time of treatment. For quantitative elucidation, a graph of intermediate RS was built with temperature (T) and time (t) as coordinates. In this graph (abbreviated as T-t planum), a series of curves of RS were created. This leads to a conclusion that same RS can be obtained by numerous different pathways. Further research on pathway equivalency based on T-t planum indicates that a low RS of 10% can be achieved definitely by different combinations of time and temperature. However, the fixation mechanism varies at different temperatures. On the equivalent pathways of higher recovery, the influence of temperature must be taken into consideration. The actual routes must be somewhat modified to achieve an expected result. This makes it possible for us to work out a best fixation pathway among all the possibilities, to eliminate the impact of heat on the mechanical properties of wood.

Effects of Periodic Temperature Changes on Stress Relaxation of Chemically Treated Wood

In order to clarify the relationship between the microstructural changes and the rheological behaviors of four chemically treated woods (delignified wood, hemicellulose-removed wood, DMSO swollen and decrystallization treated wood), the stress relaxation of wood with three different moisture contents was determined during periodic temperature changes. The experi- mental results show that after wood relaxation for 4 h at 25 °C, the stress decays sharply when the temperature increases and 2 h later the stress recovers again when the temperature drops back to the original point. The additional stress relaxation, produced after tem- perature begins to increase, is mainly caused by the thermal swelling, molecular thermal movement and the break of a part of residual hydrogen bonds. The number of hydrogen bonds and the size and amount of cavities in various treated woods greatly affect the magnitude of the additional relaxed stress and the recovery stress.

Stress Relaxation of Chemically Treated Wood during Processes of Temperature Elevation and Decline

In order to clarify the effect of drying on structural changes of DMSO swell treated and DEA-SO2-DMSO decrystallization treated Chinese fir （Cunninghamia lanceolate） wood, the stress relaxation of treated oven-dry specimens during the processes of temperature elevation and reduction and that of treated wet specimens at constant temperature were determined. A stress decrease process and a stress increase process were observed in all stress ratio curves of wood during the processes of decreasing temperature. Untreated wood, during the process of temperature reduction under higher initial temperature conditions and during the process of temperature elevation, has a larger stress decrease than treated woods. In a wet state this trend is reversed. It indicated that the drying set made treated woods have a smaller increase in fluidity of wood constituents with increasing temperature. Some bonding between decrystallization reagents and wood molecules may occur.

CHEMICAL AND PHYSICAL CHANGES OF STEAM TREATED WOOD CHIP

High dimensional stable particlcboards could be produced by usisng saturated steam treated wood chip at elevated pressures. Sample Particleboards were made from wood chip of Birch (Platyphylla). The component changes of steam treated wood chip were analysed by infrared. Infrared spectra demonstrated that the hemicelluloses in steam treated chip were less than those in untreated chip. This is one of the main reasons why steam treatment could improve particlcboard stability. The free radical concentration of steam treated chip surfaces was analysed by ESR spcctroscopy. The results showed that free radical concentration of treated chip surface was higher than that of untreated chip surface. The glueyncss of chip increased and particlcboard resin content decreased.

Properties of PEG/thermally modified wood flour/polypropylene (PP) composites

In order to improve the dimensional stability of wood-polymer composites, wood flour pre-treated by polyethylene glycol （PEG） at two different concentrations and then thermally treated at 140℃, was used as raw material to produce wood flour/poly- propylene （PP） composites at a wood content of 40%. The structure of modified wood flour was analyzed with a scanning electron microscope （SEM） and its effect on the physical and mechanical properties of wood flour/PP composites was evaluated. The SEM results indicated the ＂bulking＂ effect of PEG on wood flour, which resulted in reduced water uptake. The combination of PEG and heat treatment further improved the moisture resistance of the composites. However, PEG modification had a negative effect on the flexural modulus of rupture （MOR） and the modulus of elasticity （MOE）; whereas heat treatment partly compensated for this reduc- tion. For dynamic mechanical properties, PEG treatment decreased the storage modulus （E＇）. However, the heat treatment resulted in an increase orE＇ of the wood flour/PP composites, with the temperature of loss factor peaks shifting to a higher temperature.

不同木纤维对水泥基胶凝材料水化进程的影响研究

木纤维的加入可改善水泥基胶凝材料的抗拉强度,但只采用机械破碎及沸煮处理的木纤维对水泥基胶凝材料有缓凝、阻凝作用,阻碍了木纤维在水泥制品中的应用,为提升木质家具企业的木纤维利用率,从机械破碎的松木、杂木纤维的长径比着手,研究经碱法预处理的木纤维对水泥基胶凝材料水化进程的影响。结果表明:未预处理的杂木纤维只影响水泥早期水化热释放速率,对水泥水化热释放总量影响较小,未预处理的松木纤维具有明显的阻凝作用;采用Ca(OH)_(2)溶液浸泡可以有效降低木纤维对水泥水化的缓凝作用,与其他碱液浸泡相比,采用Ca(OH)_(2)浸泡可避免水泥胶凝体系引入其他物质。

杨木旧材高温作用后力学性能试验研究

依托新疆玉儿滚军垦旧址保护项目,采用火灾后未过火原木制作杨木旧材的标准无疵小试样,考虑温度、恒温时间两种因素高温处理试样并进行抗拉、抗压力学性能试验,探究木材顺纹和横纹方向上的主要力学性能演化规律。在试验基础上,建立了顺纹杨木旧材抗压本构模型。试验结果表明:高温处理后,顺纹木材抗压强度整体下降幅度为15%~30%,横纹木材抗压强度整体下降幅度为20%~50%;顺纹木材和横纹木材的抗拉强度均显著下降,为25%~62%。建立的本构模型曲线与试验结果相比,误差在10%以内,可适用于相应木材力学性能分析。

金玫应用木土同调法治疗胸痹心痛经验

金玫教授认为胸痹心痛病常与肝胆、脾胃功能失衡相关,肝胆在五行中属木,脾胃属土,其提出胸痹心痛病木土同调的中医辨证论治方法,肝气乘脾,心气不足证,治以培土泄木,补益心气;肝胃有热,心阴不足证,治以清肝和胃,滋阴清心;脾胃湿热,胆火扰心证,治以清热利胆,健脾燥湿;脾虚肝郁,气虚血瘀证,治以实土御木,益气活血;肝胃气滞,瘀血内停证,治以疏肝理气,活血化瘀;心肝血虚,脾气不足证,治以养肝健脾,补血活血;心虚胆怯,脾阳不足证,治以安神定志,温补脾阳。

UiO-66-NH_(2)/wood的设计构筑及高效去除水中微量重金属离子性能

矿山开采、金属冶炼、新型金属材料的发展以及城市供水系统老化所造成的重金属(铅、镉、汞、砷、铬、铜及锌等)污染问题已日趋严重.传统的水处理方法很难有效地去除低浓度的重金属污染物.本文以天然木材为载体,采用溶剂热合成法,在木材三维孔道中原位合成UiO-66-NH_(2)金属有机框架材料(MOFs)纳米颗粒,制备了UiO-66-NH_(2)/wood复合膜材料.该复合膜材料对去除水中微量重金属离子(Hg^(2+),Cu^(2+))表现出优异的性能.当处理速率为1.1×10^(2)L·m^(-2)·h^(-1)时,该复合膜材料去除水中微量重金属离子的效率仍可达到90%以上,且处理后水中重金属离子含量低于国家饮用水标准.这可归因于木材本身独特的三维孔道结构,在提高水通量的同时,还可以增加水溶液中重金属离子与MOFs颗粒的接触机会,以及孔道内均匀分布的UiO-66-NH_(2)MOFs颗粒中的—NH_(2)可以与重金属离子通过配位作用相结合.该UiO-66-NH_(2)/wood复合膜材料还具有良好的重复利用性,在连续6次循环使用后其去除效率无明显变化,有望进行实际应用.

国医大师王晞星从“木土并治”角度论治功能性消化不良经验

功能性消化不良(FD)是一种常见的无器质性改变的功能性胃肠疾病,主要表现为餐后饱胀不适、早饱感、上腹痛或有烧灼感等,易反复发作。根据其临床表现,FD与中医“胃痞”“痞满”等相似。FD病位在胃,与肝脾密切相关,情志及心理障碍因素与本病的发生也关系密切。王晞星教授从“木土并治”角度出发,认为治疗FD应当“以肝为本、顾护脾胃”,治以疏肝健脾、和胃降逆,以复中焦气机。笔者通过临床跟师随诊,发现从“木土关系”角度论治FD临床疗效显著。

热处理对木材多尺度结构及力学性能影响的研究现状

热处理是一种改善木材尺寸稳定性的重要方法,同时会引起木材多尺度结构变化,进而影响热处理材的微宏观力学性能。本文从纳米、微米、毫米三个尺度总结了热处理对木材结构单元及力学性能的影响。在纳米尺度,热处理过程中木材半纤维素大量降解导致其作为界面偶联剂的基质特性被破坏;纤维素的羟基与半纤维素降解产生的有机酸发生酯化反应,其分子间氢键以及与半纤维素连接的氢键大量断裂,引起分子链断裂,削弱了半纤维素与纤维素之间的结合强度;多糖解聚引起木质素相对含量变化,木质素自缩聚反应以及与多糖降解产物发生的交联反应是热处理后细胞壁基质力学性能发生变化的重要因素。在微米尺度,热处理木材细胞壁胞间层出现裂缝,各细胞间产生分离,微纤丝的定向排列规律性下降、倾角增大,沿微纤丝长度方向断裂,进而引起细胞壁力学强度明显下降。在毫米尺度,早晚材的横切面上由方形、圆形变成椭圆形,其中早材开裂较多;径切面上管胞和导管的胞壁变形开裂,随着热处理程度增加,胞壁出现垂直轴向断裂、纹孔破坏、木射线开裂等现象,射线薄壁细胞被大量破坏,进而引起木材的载荷承载能力下降。本文可以为深入研究热处理对木材各尺度结构及力学性能的影响机制提供参考。

氯化锌浸渍处理对樟子松热处理材尺寸稳定性和处理能耗的影响

【目的】本研究旨在探究弱酸性氯化锌溶液浸渍对热处理材的尺寸稳定性以及处理能耗的影响。【方法】采用质量分数5%的氯化锌溶液浸渍樟子松试样,并进行不同温度的热处理,通过试样吸湿后的尺寸和质量变化分析,评价浸渍–热处理樟子松试样的尺寸稳定性和吸湿性,并结合红外光谱分析、X射线衍射分析以及能耗计算,阐明浸渍–热处理对试样尺寸稳定性的影响机制和能量消耗情况。【结果】氯化锌浸渍–热处理组的性能提升效果比热处理组更明显;随着热处理温度的升高,木材的吸湿性降低,尺寸稳定性提高,热处理组和浸渍–热处理组的体积湿胀率分别从3.5%、3.4%下降到2.6%、2.1%;两种处理方式下的处理材红外吸收光谱图中均没有产生新的官能团特征峰,但羟基数量均随着温度升高而明显降低;处理材的相对结晶度呈上升趋势,热处理组和浸渍–热处理组分别由36.05%、38.77%提升到48.51%、53.04%;浸渍–热处理组试材在160℃达到的处理效果比仅进行180℃热处理达到的处理效果更好,同时因为前者的处理温度更低,所以能够减少处理过程中的能耗,在所研究的温度范围内最高可减少10%的能耗。【结论】相比樟子松热处理改性,氯化锌浸渍–热处理联合改性可以通过更低的热处理温度使樟子松达到相同的尺寸稳定性,有助于热处理工序的节能减排,对于力学性能方面的影响则需要进一步深入研究。