排序方式: 共有23条查询结果,搜索用时 15 毫秒
1.
Makoto Kiguchi Yutaka Kataoka Hiroshi Matsunaga Koichi Yamamoto Philip D. Evans 《Journal of Wood Science》2007,53(3):234-238
The market for wood-fiber plastic composites (WPCs) is expanding rapidly in many countries including Japan, where WPCs are
mainly used for exterior products. In such applications, WPCs undergo undesirable color change, chalking, and shrinkage and
swelling, and accordingly there is a need to better understand the mechanisms responsible for the weathering of WPC and develop
methods of improving their weathering resistance. In this study, weatherability of WPC was assessed by natural and accelerated
weathering trials. Discoloration (whitening) of WPC during exposure was caused by degradation of both wood and plastic. Darker
color pigments as additives improved the color stability of WPC; however, chalking on the surfaces still occurred. The color
stability of WPC was improved by application of exterior coatings. Preweathering of WPC (before coatings were applied) increased
the absorption of coatings by the WPC and had a positive effect on the color stability and prevented chalking of the composites.
Parts of this study were presented at the IUFRO XXII World Congress Meeting, Brisbane, August 2005 and the IAWPS 2005, Yokohama,
November 2005 相似文献
2.
云南铁杉干燥过程中变色的控制 总被引:6,自引:0,他引:6
云南铁杉在干燥过程中的变色问题是困扰许多木业企业的一个技术难题。笔者通过近几年的研究和实践 ,从其木材组分入手 ,分析了在干燥过程中云南铁杉变色的原因 ,制定了减轻变色程度的干燥工艺措施 ,使铁杉干燥过程中的变色率降至 10 %以内 ,其质量达到国标规定相应的技术指标 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):179-191
The effects of felling season, log storage and kiln drying on stemwood discoloration of sixty mature silver birches ( Betula pendula ) were studied and provided with CIEL*a*b* colour coordinates. The colour differences were expressed as j E* including split up of j L*, j a* and j b*. The results showed that fresh wood colour depends on the felling season: light and pale colours were recorded for samples taken from autumn- and winter-felled trees, whereas the colour of fresh wood was considerably darker if the felling took place in the spring or summer. After storage, notable changes in colour were observed. After drying, all samples showed low lightness, moderate redness and relatively high yellowness under the drying conditions used in the study regardless of the felling season or duration of storage. The main colour component responsible for the discoloration was lightness, while chroma values redness and yellowness played a minor role. 相似文献
5.
泡桐材变色类型的确定及变色真菌的鉴定 总被引:10,自引:0,他引:10
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。 相似文献
6.
Tadashi Oikawa Toshiya Matsui Yasunori Matsuda Teruko Takayama Hitoshi Niinuma Yasuyo Nishida Kazuo Hoshi Mitsuyoshi Yatagai 《Journal of Wood Science》2006,52(2):140-146
Volatile organic compounds (VOCs) from wood and their effects on artifacts are of intense interest to museum staff who must
strictly manage the preservation environment. In this study, the causal substances of deterioration were inferred by comparison
with laser Raman (LR) spectra of deterioration products. The artifact samples were deteriorated using VOCs from woods (WV
test), and using specific substances that occur in wood VOCs (SV test). The deteriorated samples were analyzed by LR spectroscopy
and the results of the WV and SV tests were compared.
Hinokitiol and acetic acid were found to be two of the main causal substances of deterioration in western red cedar. Deterioration
of iron and copper by spruce did not appear to be caused by acetic acid, as is generally assumed, but by some other unknown
compound(s). Sensitivity to wood-based VOC components depended on the type of artifact. In western red cedar, mitsudasou (litharge) was very sensitive to acetic acid, while other artifacts were sensitive to hinokitiol. The LR method used in this
study is very useful for the inference of causal substances of deterioration based on the detection of small amounts of deteriorated
products such as those generated by deterioration due to wood VOCs.
Part of this article was presented at the 25th Annual Meeting of the Japan Society for the Conservation of Cultural Property,
Kyoto, June 2003 相似文献
7.
节子的变色现象严重影响木材质量,了解节子变色规律及其影响因素是确定合理修枝的重要依据.以黑龙江省孟家岗林场地区49年生的水曲柳(Fraxinus mandshurica)人工林为研究对象,采用节子剖析技术分析自然整枝条件时水曲柳节子愈合时间与变色长度的变化规律.结果表明:水曲柳节子平均愈合时间约为6.7 a,约91.1... 相似文献
8.
酸碱对防止泡桐木材变色的影响 总被引:2,自引:0,他引:2
对酸碱度影响泡桐木材色泽进行了研究,并对弱碱溶液防止泡桐木材变色的作用做了试验与分析。结果表明:酸碱度影响泡桐木材颜色变化,在偏酸条件下泡桐木材的白度易于向劣化方向发展,总色差升高;偏碱条件下泡桐木材白度提高,总色差下降,色泽指标明显趋好。0.25%的弱碱溶液改善泡桐木材的渗透性,能溶出木材内部部分内溶物,可浸提的内溶物中多含有变色前驱物质,促进了防止泡桐木材的变色作用,而又不会污染泡桐木材材面。防变色剂具有一定的防变色作用,但只用防变色剂预防泡桐木材变色容易出现返色现象,综合使用弱碱溶液与防变色剂防治效果比单独使用防变色剂效果好,经0.25%的弱碱溶液同防变色剂处理可使泡桐木材防变色效果内外趋于一致。 相似文献
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新型五色草花坛从景天科植物中选出,在自然低温条件下和干旱季节中试验,比老五色草抗寒抗旱,更具有应用价值。用于花坛造型显现出红、绿、黄、粉和紫粉五种色颜动态变化,不同于老五色草的静态拼色,而且,整体越冬完好。母株冬储和繁殖均在露地进行,改变了老五色草在加温温室内越冬和需要在保护地繁殖的传统方式,花坛模纹时间提前1个月,观赏期延长60d,一年建植多年享用。新型五色草可取代现行的老五色草,在寒冷地区广泛应用。 相似文献