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1.
对马尾松及花旗松木材试样进行了气相硼法木材防腐处理的研究。考察了马尾松木材试样的含水率、防腐处理温度、处理压力及进料温度等因素对防腐处理后试样中硼酸含量的影响。得到了气相硼法防腐处理的优选工艺条件:木材试样的含水率10%,防腐处理温度75℃,防腐处理真空度97.325kPa,进料温度32℃。防腐处理1h,马尾松试样中硼酸的含量为6.13%。对花旗松心材气相硼法防腐处理实验结果表明:对难渗透的木材渗透效果也很好。电子显微镜观察的结果表明:经气相防腐处理和液体浸泡防腐处理试样的细胞壁上均沉积了硼酸固体物质,但硼酸沉积量前者的远远大于后者的。对防腐处理前后试样的机械性能及尺寸变化测试结果表明,木材试样的冲击强度与抗弯弹性模量下降很小,而抗弯强度反而提高了4.6%;木材尺寸变化很小。 相似文献
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新西兰辐射松的干燥和防腐处理李瑞芝(山东省林业厅)新西兰人工造林总面积为130万公顷,其中90%是辐射松。为提高辐射松木材的利用价值,经过长期的探索,形成了一套完整、科学的辐射松木材干燥和防腐处理方法。这些方法,对处理其它木材,尤其杨树木材,具有较高... 相似文献
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木材材色处理是木材改性的重要内容。木材改性的目的是通过各种物理、化学处理,使木材的缺点得到不同程度的改进,使优点能进一步加强,更适合于应用。将能改进木材材质和性能的各种处理方法统称为木材改性。广义的木材改性还包含在营林技术方面,加强森林抚育,提高林木材质等。在林产工业范围内的木材改性大致可包括以下九方面内容:1)材色处理;2)尺寸稳定处理;3)可塑化(软化)处理;4)增强处理;5)塑合木(WPC);6)防腐、防虫处理;7)阻燃处理;8)防风化处理;9)木材塑料化等。现就目前应用较广泛又急待解决的材色、阻燃… 相似文献
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国外木材防腐现状、发展趋势及我国的对策 总被引:1,自引:0,他引:1
世界各国普遍重视木材防腐工作。70年代以来, 发展中国家的木材防腐发展迅速。当今世界木材防腐的发展趋势为: 防腐品种趋向多样化, 保护剂向高效、低毒或无毒的方向发展, 处理技术不断提高。我国的木材防腐数量小、品种少、差距大。作者提出了发展我国木材防腐的对策。 相似文献
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国外木材防腐技术和研究现状 总被引:15,自引:0,他引:15
从木材防腐剂、防腐处理工艺、改性处理及环境特性等几个方面对国外的木材防腐技术及研究现状进行较为系统、全面的介绍,并在此基础上指出木材防腐研究的几个主要方向.木材防腐剂的发展趋势是近期以水载防腐剂为主导,以开发综合性能优良的不含金属的有机防腐剂作为未来的发展方向;木材防腐处理工艺的重点在于增强防腐剂在木材中的渗透性,加速防腐剂与木材之间的固着反应以及开发新型的防腐处理工艺以适应新的防腐剂的需要.改性处理方面主要介绍木材的热处理和化学改性处理在防腐方面的应用现状.木材防腐处理的环境特性则着重介绍LCA技术(生命循环分析技术)以及防腐处理材的废弃处理问题.另外,还简要介绍木材防腐研究机构和协会、木材防腐标准等方面的情况.本文旨在使国内的木材研究者对当前木材防腐技术和研究有一个总体的认识,并在此基础上结合国内的实际情况,发展适于处理中国国内树种及适合市场需求的木材防腐技术,为更科学、更高效地利用国内木材资源提供新途径. 相似文献
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木材在生产应用过程中易受真菌侵害导致木材性能劣化,极大地限制了木制品在户外推广应用。近年来,为了增强木材防腐技术开发的理论基础,木材腐朽机理得到普遍关注与研究。文中从以下3个方面梳理、归纳、总结木材腐朽机理研究现状:1)木材腐朽过程中结构成分与性能的变化规律;2)木材酶降解理论;3)木材非酶降解理论。在此基础上,阐明现有木材腐朽机理研究中存在的问题及今后重点研究方向,以期为绿色环保型木材防腐技术的研发提供理论指导,为2030年我国实现“碳达峰”提供战略技术支撑。 相似文献
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短周期桉树与相思人工林木材处理性及浸注性研究 总被引:1,自引:0,他引:1
通过测定4-9年生的桉树和马占相思木材密度,并用5%CCB防腐剂以常温常压浸泡法,热冷槽法及劳菜空细胞加压进行防腐处理,再测定处理材的防腐吸收量及渗透深度来评估木材的处理性及浸注性,结果表明,1.速生人工林的赤桉,尾叶桉,马占相思木材属较难处理性木材;2.CCB防腐剂对桉树和马占相思木材有浸注性较好,硼渗透较深且均匀,铜较浅.3.可用热冷槽法和加压法对木材进行防腐处理,这有利于药剂的渗透及提高工效 相似文献
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日本;三井物产林业公司开发的木材干燥/REO防腐处理装置,已开始商品化生产。并在日本市场销售。该装置的最大特点是,避开以往先对木材进行干燥,然后再做防腐处理的繁琐工序,与以往做防腐处理相比,至少可以节约50%的防腐处理成本。另一特点是使用6000L废机油一次可对6m^3木材同时进行干燥和REO防腐处理,废机油为热源。加热过程中湿木材的水分变成蒸汽, 相似文献
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The leaching of chromated copper arsenate (CCA) components from unfixed wood immersed in water is modeled in three dimensions
using an analytical model of simultaneous diffusion and reaction. Parameters for the model were determined by laboratory leaching
experiments with small uncoated wood samples, departing from previous approaches where diffusion coefficients are measured
in one dimension at a time. The diffusion coefficients and reaction rate constants of Cr6+, total Cr, Cu, and As in unfixed CCA-treated red pine (Pinus resinosa Ait.) and southern pine (Pinus sp.) were estimated, assuming first-order reaction rate equations and independent Fickian diffusion for all components. Estimated
reaction rate constants and diffusion coefficients were not significantly affected by sample dimensions except for very severe
longitudinal leaching from short samples. The predictive ability of the model using diffusion coefficients determined from
immersion of small lab samples was evaluated by leaching experiments in a spray booth of southern pine lumber at 21 and 60°C,
and red pine pole sections at 21°C. The predictive ability of the model was mixed, but in all cases represents a significant
improvement over small-block leaching models which do not account for the diffusive nature of the leaching process. 相似文献
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Furfuryl alcohol has a sufficiently small molecular size, which allows impregnation into wood and can be polymerized in the cell walls. Polymerization can be accomplished using a catalyst, heat or penetrating radiation. This research illustrates a natural wood polymer composite (NWPC) that was obtained under the catalytic effect of borates. Furfuryl alcohol (FA) and borates were mixed at different ratios before treatment. When borates alone are used, they were totally leached from wood after cyclic leaching periods. However, this was not encountered with the mixture of furfuryl alcohol and borates. Furfuryl alcohol considerably improved antiswelling efficiency by about 85% for both Japanese cedar ( Cryptomeria japonica) and Scots pine ( Pinus sylvestris L.) wood specimens. Results of the leaching tests of borate indicated that boric acid readily lost its boron content in the early cycles of the leaching periods and the highest leaching rate of boron was observed at the first leaching cycle (512 ppm). When furfuryl alcohol mixed with borates, boron was released to the leaching water at slower amounts, suggesting the possibility of longer protection of treated wood in service. 相似文献
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Tetsuya Sano Satoru Miura Hitomi Furusawa Shinji Kaneko Takahiro Yoshida Takashi Nomura Seiji Ohara 《Journal of Wood Science》2013,59(4):307-320
To evaluate the characteristics of wood ash as fertilizer, composition of inorganic elements and the leaching behavior were studied. The leaching behavior was evaluated by three leaching methods using different solvents (water, hydrochloric acid, and acetic acid: Japanese leaching test Nos. 18 and 19 and modified toxicity characteristic leaching procedure prescribed by the US Environmental Protection Agency). The ash composition varied according to raw materials for fuel and ash collection systems. Concentration of Na, Al, Si, and V became higher in bark ashes while that of K became higher in wood ashes. Pb, Cd, Se, and Zn were more volatile and enriched in fly ashes. Of the nutrient elements, K showed high water solubility and its phytoavailability also appeared high, although the amount of water-soluble K was low in bark ash. Ca and Mg had intermediate solubility while P was less soluble in both water and acetic acid. The amount of hazardous substances having leached was low for most, but not all the ashes, in terms of Pb, Cr and As. Nevertheless, the phytoavailability of these hazardous substances after their application to the forest appeared low, due to their amphoteric leaching behavior and the acidity of Japanese forest soils. 相似文献
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文章研究了SGB硼防腐剂处理的马尾松试材经环保型水溶性涂料(WAQ)、天然植物油涂料(TRQ)及木材用户外涂料(KJQ)分别处理后的硼流失性能。结果表明硼防腐处理材经涂料再次处理后试件的抗流失性能均有改善,其中效果最好的是TRQ涂料,它与SGB共同处理的试件比单用SGB防腐剂处理的试件硼的抗流失率平均提高了36.5个百分点。 相似文献
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泡桐木材流体渗透性与扩散性的研究 总被引:11,自引:1,他引:11
本文论述了泡桐木材流体渗透性,扩散性,吸着水与自由水的吸着与吸收动力学特性,密度和干缩性以及电镜观察结果;阐明了泡桐木材具有流体可渗透及可扩散路径,有着输导流体的天然机制,水、热处理难易一般;泡桐材本身并不具有隔潮耐湿性,但由于它密度低,胀缩小,变形和开裂的可能性亦小,用它干燥后制成的箱盒容器的密封性、隔潮耐湿性较好。 相似文献
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In Japan, ammoniacal copper quaternary wood preservatives type-1 (ACQ-1), which contains copper and benzalkonium chloride
as its active ingredients, is among the most widely used wood preservatives in the pressure treatment of wood. Benzalkonium
chloride (BAC) in commercial ACQ-1 products mainly comprises C12 and C14 homologues. In the present study, the leaching characteristics
of these BAC homologues were investigated using the heartwood and sapwood portions of Japanese cedar, Japanese larch, and
Sakhalin fir treated with ACQ-1 and 1% monoethanolamine (MEA) solution containing equimolar amounts of homologues. Distilled
water (DW) and artificial seawater (SW) were used as leaching media. Consequently, it was observed that the leaching rate
of the C12 homologue tended to be higher than that of the C14 homologue in DW. The leaching of C12 homologues was accelerated
by using SW, resulting in a significantly higher leaching rate than the C14 homologue using SW. It was thought that the difference
in the hydrophobicities based on alkyl chain lengths resulted in these phenomena. However, when the heartwood portion of Japanese
larch was treated with the homologues in MEA, the leaching rate of the C14 homologue was significantly higher than that of
the C12 homologue. 相似文献
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This study was designed to reveal impregnation ability and to enhance leaching resistance of boron from borate-treated wood. Vapor boron treatment was applied in compressed and uncompressed states at high temperatures such as 180 and 200°C for 6, 8 and 15 min. Following ten-cycle leaching periods, amounts of boron leached from vapor boron treated wood was measured by ion chromatography. According to the results, boric acid can be vaporized under heat and can be impregnated into wood. Success of the technique can be increased by increasing vapor pressure in a closed chamber. Leachability results proved the boron vaporization along with water vapor at various ratios depends on the process variables. These results have importance on dry wood treatment under heat by boron vapor with a little water presence which does not necessitate a further drying process. 相似文献
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Maria Jonsson 《Journal of Wood Science》2012,58(3):251-258
Sprinkling wood with water is a common method for protecting wood during storage, yet the polluted runoff generated by the log yard is a major drawback. To study bark’s ability to leach pollutants from logs, the Picea abies, Pinus sylvestris, and Betula pubescens wood species were submerged with and without bark for 6?weeks. The water was analysed during the study for total organic carbon, phosphorus, nitrogen, colour, pH, and distillable phenols. The results showed that the leaching from carefully debarked wood is lower than that of both gently debarked wood and intact wood. Storing carefully debarked logs is a viable method for reducing pollutants in log yard runoff. 相似文献
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Toshiro Harada Hiroshi Matsunaga Yutaka Kataoka Makoto Kiguchi Junji Matsumura 《Journal of Wood Science》2009,55(5):359-366
The weatherability and combustibility of fireretardant-impregnated wood during accelerated weathering for up to 2000 h were
evaluated. The ability of coating to retain fire-retardant chemicals against leaching was also examined using four coating
systems (water-borne or solvent-borne, pigmented or clear, film-forming or penetrating). Furthermore, the distribution of
fire retardants in the specimens was observed by scanning electron microscopy in combination with energy dispersive analysis
of Xrays (SEM-EDX). The fire performance of the specimens during weathering depended on the chemical retention, and was maintained
at a quasi-noncombustible material level if the chemical retention was above 150 kg/m3. The maximum duration of accelerated weathering to keep this retention was 250 h for the uncoated specimens, but increased
to over 1000 h for pigmented coatings. SEM-EDX revealed that the fire retardants were accumulated in the cell lumina throughout
the wood tissues. However, in the uncoated samples, the leaching of fire retardants occurred for surfaces exposed to light
and water, and was observed down to a depth of ∼150 μm after 500 h. The leaching depth extended throughout the specimen after
1000 h. In contrast, the fire retardants still remained in samples finished with a solvent-borne pigmented penetrating coating
even after 1000 h due to their relatively high chemical retention. 相似文献
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酚类阻燃剂处理杉木热解过程的热动力学研究 总被引:8,自引:0,他引:8
抗流失阻燃剂是当前阻燃剂研究开发的一个重要方向。采用TG DTA热分析技术研究了酚类阻燃剂处理杉木热解过程各阶段的木炭产量和热动力学参数。结果表明 ,酚类阻燃剂阻燃处理杉木的产炭量因苯环上取代基不同而不同 ,其阻燃作用的大小顺序为 :氨基 >溴 >硝基。同时具有氮元素和溴元素的二溴硝基苯酚和二溴氨基苯酚的产炭量都大于相应的单取代苯酚衍生物。浸泡实验后 ,磷酸氢二铵的产炭损失率是二溴硝基苯酚的 5倍。阻燃处理后产炭量的增大总是对应于炭化阶段热解反应峰温降低、反应速率常数增大 ,但产炭量的增大程度与这些热动力学参数的改变是负相关的。因此 ,氮和溴的苯酚衍生物不仅对木材具有很强的阻燃作用 ,而且具有很强的抗浸泡能力 ,氮元素的阻燃作用与其在阻燃剂中的氧化态关系极大 ,氮和溴在木材阻燃中存在协同增效作用 ,阻燃处理对木材的吸湿性也有影响。 相似文献