思茅松人工幼林“3414”施肥试验

2007年8月,在景谷县具有代表性、长势相当的思茅松人工幼林中,采用"3414"试验设计,对氮、磷、钾3种肥料的不同配比组合进行了施肥试验。结果表明:立地条件对思茅松人工幼林的生长影响较大,思茅松人工幼林施肥应区别不同立地条件采用不同的施肥配比组合,地位指数级为12的立地条件较佳组合为50 g氮肥+150 g磷肥+80 g钾肥,地位指数级为14的较佳组合为100 g氮肥+75 g磷肥+80 g钾肥,地位指数级18的较佳组合为100 g氮肥+150 g磷肥+80 g钾肥。     

PF预聚物合成工艺对杨木理化性能的影响

采用3种摩尔配比工艺条件下的低分子量酚醛树脂浸渍杨木,对处理后产品的理化性能指标进行比较,结果表明:处理液浸渍过的杨木素材抗弯强度明显提升,幅度在30.3%～33.7%之间;处理液浸渍过的杨木体积膨胀率明显下降;经过处理杨木的氧指数达到30。     

水培条件下氮磷钾配比施肥对木荷幼苗生长的影响

为探究木荷幼苗生长对不同氮磷钾配比营养液的响应情况,为木荷壮苗培育合理施肥提供科学的理论依据,选择1月龄木荷幼苗作为试验材料,以Hoagland营养液为母液,进行氮磷钾3因素6水平缺素试验,在水培条件下研究不同氮磷钾配比对木荷幼苗生长的影响。结果表明:不同的氮磷钾营养液配比中,木荷幼苗的各项指标变化趋势基本一致,氮磷钾肥对木荷幼苗生长的影响表现为PKN,处理15表现最佳,处理12幼苗长势最差;木荷幼苗的株高、生物量、SOD、POD、CAT、SP均表现出随着施肥水平的提高先升高后降低的变化趋势,Pro和MDA在高水平施肥时显著增加。研究显示,以Hoagland液为水培营养液母液,氮磷钾水平分别为母液中氮磷钾元素浓度的1、1和0.5倍时,木荷幼苗生长最佳。     

橡木贴面实木复合地板凹凸表面热压工艺研究

三聚氰胺浸渍橡木薄单板贴面实木复合地板是参考三聚氰胺浸渍纸贴面生产工艺生产出的表面凹凸实木复合地板。使用三聚氰胺胶黏剂、固化剂、渗透剂、脱膜剂（配比为500：1：1：1）混合液浸渍橡木薄单板,然后在真空度为0.08 MPa时保压浸渍5 min,在大气条件下放置30 min,取出后再放入90℃鼓风干燥箱中干燥10 min。浸渍完成的橡木薄单板与基材经热压成型为表面凹凸的实木复合地板。考虑热压温度、热压压力、热压时间对其凹凸表面成型的影响,每个因素取4个水平,制定因素水平表,选择正交表进行试验。对试验结果进行浸渍剥离及表面纹理深度的测量分析,得到最优的热压工艺条件为温度150℃、压力1.2 MPa、时间70 s。三聚氰胺浸渍的橡木贴面复合地板表面纹理、色泽、手感都更加接近自然。     

一品红无土栽培试验

用5种基质和6种不同的营养液,对一品红生长的影响进行了对比试验,结果表明：以蛭石和珍珠岩组成的基质A,搭配Y2和Y3营养液配方的处理效果较佳。     

N、P、K营养元素不同配比对马占相思苗期生长的影响

采用N、P、K 3营养元素 5个水平配比试验 ,分析不同配比对马占相思苗期生长的影响 ;通过正交试验 ,确定马占相思苗木对各营养元素的实际需求水平。结果表明 ,P素对马占相思苗期生长影响最大 ,其次为K素 ,而N素的影响相对较小。不同水平的N、P、K配比对试验苗有不同的影响 ,其中 ,N∶P∶K最佳配比为 :190∶2 5∶16 0 (mg·L- 1)。     

一品红无土栽培试验

选用5种基质和6种不同的营养液，比较其对一品红生长的影响。试验结果表明：以蛭石和珍珠岩组成的基质A搭配Y2和Y3营养液配方的处理效果较佳。     

阿维菌素乳油注干防治松材线虫病的效果

采用浸渍法测定阿维菌素乳油1 000,2 000,3 000,5 000,7 000倍液对松材线虫的毒杀效果,结果表明,阿维菌素乳油对松材线虫有较强的杀灭活性,药剂各配比液处理24 h后线虫死亡率达92%,其中,配比度低于5 000倍液的毒杀死亡率超过97%,与7 000倍液的毒杀死亡率之间差异极显著;阿维菌素乳油在林间注干防治松材线虫试验结果表明,防治效果十分显著,马尾松和湿地松注药1次,在1 a时间内未发现病害枯死木,有效地抑制了松材线虫病的发生。     

杨木微纳纤丝改良秸秆纤维板性能的研究

通过不同浓度微纳纤丝/MF混合液对秸秆纤维板进行不同浸注时间处理后,分析可知:微纳纤丝的浓度越大,对提高秸秆纤维板的静曲强度和弹性模量效果越好;而增加浸渍时间虽然有利于提高秸秆纤维板的平均密度,但同时会提高其密度梯度。较佳的工艺参数分别是秸秆纤维板密度:0.8g/cm~3;微纳纤丝浓度:1.0%;浸渍时间:8h。     

竹重组材浸渍纸饰面工艺

通过正交试验,考察了树脂含量、残留挥发分、热压压力和热压时间等工艺因素对浸渍纸饰面竹重组材的表面胶合强度和耐磨性能的影响,探讨了浸渍纸饰面生产的较佳工艺参数。试验结果表明：树脂含量和残留挥发分对浸渍纸饰面竹重组材的表面胶合强度和耐磨性能影响显著。在试验条件下,适宜的饰面工艺为树脂含量200％,残留挥发分7％,热压压力2.9 MPa,热压时间40 s。     

Relationship between wood porosity,wood density and methyl methacrylate impregnation rate

Abstract

Mercury intrusion porosimetry (MIP) was used to evaluate the impregnation mechanisms of wood by methyl methacrylate (MMA) through examining the changes in porosity, pore volume, pore size distribution and bulk density of solid wood before and after MMA impregnation. Porosities of MMA-impregnated (hardened) wood samples were lower than those of solid wood samples for six studied species, five hardwoods and one softwood. Densities of hardened wood were enhanced from 45 to 130% depending on the species. The pore volume available for mercury intrusion was shifted from pore d>0.1 µm for solid wood to pore d≤0.1 µm for hardened wood. A pore diameter of 0.1 µm was used as the transition point for MMA impregnation and the increased mercury penetration below this point was attributed to the MMA polymer pore structure. Porosity as an intrinsic property of wood appears to be the main determinant of impregnation rate and polymer retention, especially for porosity with pore diameter >0.1 µm. The results indicate that the MIP technique is an effective tool with which to study the impregnation process.     

Copper complexes grafted to functionalized silica gel as wood preservatives against the brown rot fungus <Emphasis Type="Italic">Coniophora puteana</Emphasis>

Wood modification with siloxanes bearing amino groups with copper-linking function was carried out by a sol–gel process. Tetraethoxysilane (TEOS) and 3-aminopropyltriethoxysilane (APTES) were the main components. Two different procedures were followed: a two-step process (impregnation with the TEOS/APTES mixture followed by dipping into a copper sulphate solution) and a one-step process (impregnation with a homogeneous sol mixture of TEOS, APTES and copper (II) chloride). The obtained materials were characterized by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis. The determination of copper content before and after leaching was performed by atomic absorption spectroscopy. The efficacy against the brown rot fungus Coniophora puteana was tested by an accelerated procedure. SEM analyses showed that silicon penetrated into wood, while copper is effectively drawn into wood only in the one-step treatment. Copper fixation to the silica gel proved to be adequately strong. Both sol–gel treatments gave good protection against Coniophora puteana.     

Impregnation and mechanical properties of three softwoods treated with a new fire retardant chemical

Three softwoods, Sugi (Cryptomeria japonica), Korean Pine (Pinus koraiensis) and Hinoki (Chamaecyparis obtusa), were vacuum–pressure impregnated with a fire retardant chemical consisting of ammonium phosphate polymer (APP), guanyl urea phosphate (GUP), phosphonic acid and a minor amount of additives. The variation in impregnation between and within wood species was investigated. A significant relationship and similar trends were found between fire retardant chemical (FR) uptake and specific gravity (SG), as well as void volume filled (VVF) and SG. Moreover, the effects of fire retardant treatment on mechanical properties, including modulus of rupture (MOR), static modulus of elasticity (MOE) and dynamic modulus of elasticity (DMOE), were evaluated. The results indicated that the trend of impregnation and regression function varied between species and positions within the same species. However, the relationship of SG and chemical uptake and that of VVF and chemical uptake could be represented by a positive linear regression, and the trends were similar between wood species. Both of SG and VVF increased with increasing FR uptake. After fire retardant treatment, the MOR and static MOE were reduced compared with before treatment. Conversely, the DMOE increased after treatment.     

冷等离子体和2D树脂基防护剂对毛竹材的防护效果

采用滑动弧冷等离子体对竹条和圆竹筒进行处理,并将处理后的样品进行复合型防护药剂加压浸渍处理。采用质量增加率、平衡含水率、湿胀率以及竹条和竹筒的抗压强度等指标来考察防护药剂处理后对竹材性能的影响,并观察竹条和圆竹筒防护处理后的发霉情况。实验结果表明,竹条和圆竹筒表面在加压条件下对二羟甲基二羟乙基乙烯脲(2D树脂)+戊唑醇与丙环唑(PT)+碘代丙炔基氨基甲酸丁酯(IPBC)复合型树脂防护剂的渗透性和附着性得以提升,表现为竹条和圆竹筒经滑动弧冷等离子体和防护药剂加压浸渍处理后质量增加率提高,而平衡含水率和湿胀率下降。对竹条和圆竹筒的质量增加率、平衡含水率、湿胀率和抗压强度产生积极影响的顺序为:冷等离子体处理+加压浸渍防护药剂>加压浸渍防护药剂>未经任何处理的竹条和圆竹筒。此外,竹节的多少也对竹材的质量增加率、平衡含水率和湿胀率产生影响,影响顺序为:无节>单节>双节。处理后,竹条和圆竹筒具有优异的防霉特性,存放半年后,圆竹筒仍能保持原来的物理特征,竹条和圆竹筒表面和端部均无发霉、腐朽和开裂现象。     

不同干燥方法对杉木人工林木材浸注性的影响

采用高频真空干燥、常规窑干和高温干燥3种方法对杉木人工林木材的心、边板材进行干燥处理,用毛细管上升法评价干燥后试样的浸注性能,用半薄切片法测定干燥试样具缘纹孔的闭塞率,最后用扫描电子显微镜观察干燥试样微观构造的变化,比较分析3种干燥方法对杉木人工林木材浸注性的影响机理.结果表明:对于杉木边材,经高频真空干燥后试样的浸注性显著高于常规干燥和高温干燥后试样的浸注性,后2种干燥方法对试样浸注性影响的差异并不显著;对于杉木心材,高频真空干燥与高温干燥后试样的浸注性存在显著差异,而高频真空干燥与常规干燥之间、高温干燥与常规干燥之间对试样浸注性的影响差异均不显著;3种干燥方法处理后,杉木边材的浸注性均显著高于心材的浸注性;具缘纹孔的闭塞率较低以及部分具缘纹孔周缘破裂是高频真空干燥后木材浸注性提高的主要原因.     

Effect of nanofillers on flame retardancy, chemical resistance, antibacterial properties and biodegradation of wood/styrene acrylonitrile co-polymer composites

Wood polymer nanocomposites (WPNCs) based on simul wood (Bombex ceiba, L.) were prepared by impregnation of styrene acrylonitrile copolymer, γ-methacryloyloxy trimethyl silane-modified TiO₂, SiO₂ nanoparticles and nanoclay intercalating mixture through vacuum impregnation. The impact of nanofillers on the physical properties, flame retardancy, water resistance, anti-swelling efficiency and biodegradability of the resultant WPNCs was investigated. Remarkable enhancement in wood properties such as flame retardancy, water resistance and anti-swelling efficiency was achieved with the treatment. The results showed that all the properties were maximum for wood samples treated with SAN/TiO₂ (0.5 %)/SiO₂ (0.5 %)/nanoclay (0.5 %). The presence of TiO₂ nanoparticles in WPNC exhibited antibacterial activity. The resistance to biodegradation was observed by incorporation of nanofillers into wood.     

真空浸渍法制备纳米Ag/TiO_2木基复合材料的工艺优化

近年来,纳米Ag/TiO_2防霉剂因具有化学性质稳定、催化活性高、成本低、环境友好等特点而受到广泛关注。但纳米Ag/TiO_2极易团聚,其使用范围和效果受到了限制。笔者采用真空浸渍法,得出纳米Ag/TiO_2防霉剂浸渍木材的理想工艺和防霉性能。通过直观分析和方差分析探究真空度、真空时间、防霉剂浓度三因素对樟子松载药量和抗流失率的影响。采用模糊数学综合评判法对载药量和抗流失率进行综合评判。研究发现,防霉效果较浸渍前提高14.5倍,防治效果达到96.67%。     

High-yield pulping of aspen wood: Relation between pulp properties and fibre characteristics by multiple linear regression

Summary High-yield pulps have been obtained by means of steam explosion pulping. This process was carried out as follows: 1) chips soak impregnation (60 °C, 24 h, L/C = 6) in solutions containing 8% Na₂SO₃ and a variable concentration of either Na₂CO₃ or NaHCO₃, ranging from 0 to 2%; 2) cooking at high temperature (190–200 °C) for short time (2-1 min); 3) rapid pressure release. This work shows that mechanical properties were substantially improved when adding a second chemical to the Na₂SO₃ impregnation solution. Moreover, refining energy requirement was significantly reduced. However, the higher chemical charge used made the optical properties drop. In this paper, mathematical models have been proposed in order to accurately predict specific refining energy and paper properties from sulfonate content and pulp yield. In addition, the relative importance of these two parameters has been studied.Thanks are due to the Natural Science and Engineering Council of Canada (NSERC) and Fonds pour la Formation de chercheurs et l'aide à la recherche of Quebec (FCAR) for their financial support.     

增强-阻燃处理改善柳杉木材的性能研究

采用不同质量分数的低分子量三聚氰胺-脲醛树脂(MUF),及其与硼酸、硼砂复配的改性液,分别对柳杉木材进行浸渍处理。结果表明:树脂溶液和复配改性液均对木材具有良好的渗透性,且木材增重率随改性液质量分数的增大而增加,两种改性液均能有效提高柳杉的物理、力学和阻燃性能。     

炭化竹板环氧树脂浸渍量的研究

采用常规浸渍的方法,炭化竹板的环氧树脂浸渍量低。本研究针对这一问题,采用加压浸渍的方法来提高炭化竹板的环氧树脂浸渍量。试验证明,通过加压的方式可明显提高炭化竹板的环氧树脂浸渍量。这为进一步研究炭化竹板与木材复合打下基础。