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51.
竹炭吸湿性的初步研究 总被引:8,自引:0,他引:8
选用箱式电阻炉和土窑烧制的竹炭,在不同温度和湿度条件下进行竹炭吸湿性变化的试验.结果表明:(1)500℃、600℃、800℃和土窑(二)的竹炭其吸湿性与温湿度有较显著关系;而700℃竹炭和土窑(一)竹炭的吸湿性与温湿度之间没有显著关系.在一定温湿度范围内,湿度对竹炭吸湿性的影响比温度显著.(2)不同炭化温度之间的竹炭其吸湿性不同.800℃的竹炭其吸湿性最大,其值为11.5%,500℃的竹炭最小,其值为8.6%;600℃的竹炭8.8%;700℃的竹炭为11.3%.(3)不同土窑的竹炭其吸湿性有显著差异.土窑(一)和土窑(二)的竹炭吸湿值分别为9.8%和6.4%. 相似文献
52.
This study evaluated the protection effectiveness of alcohol-borne reagents for the green color of ma bamboo (Dendrocalamus latiflorus Munro) and moso bamboo (Phyllostachys pubescens Mazel). The results show that the types and concentrations of alcohol-borne reagents, the kinds of solvent, and the conditions
of treatment greatly affected the green color of these two bamboo species. Without alkali pretreatment, an excellent green
color protection (a* = −14.5) was obtained when the ma bamboo culms were treated with 0.5% methanol-borne copper chloride (CuCl2) at 60°C for 30 min. Similar results were also obtained when ma bamboo culms were treated with 0.5% methanol-borne copper
nitrate [Cu(NO3)2] at 60°C for 2 h (a* = −13.5). For moso bamboo, an attractive green color in the bamboo culms was achieved by treating the specimens with 1%
methanol-borne copper acetate [Cu(CH3COO)2] at 60°C for 30 min. The a* value of treated specimens was −13.3. In addition, results demonstrated that ultrasonic treatment was more effective on
green color protection than conventional water bath treatment. When moso bamboo was treated with 1% copper acetate at 60°C
in an ultrasonic bath for only 15 min, a remarkable green color with an a* value of −13.6 was obtained on the bamboo epidermis. 相似文献
53.
湖州安吉县每年大量的竹制品出境,笔者针对当前竹制品检疫工作中产品水分含量、抽样方法、检疫项目这三个关键点,简要分析了存在的问题以及探讨解决的方法. 相似文献
54.
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56.
1987年冬和1988年冬二次从浙江引种六个笋用竹种1.56万株,成活率达90%以上,发笋率达80%以上,新竹的秆基粗度已达到母竹的粗度,引种是成功的。本文分析了各引种环节的技术效果。 相似文献
57.
“嘉兴市优良笋用林开发”课题组 《竹子研究汇刊》1991,9(2):68-74
嘉兴市共有十五种栽培竹种,其中以毛竹、早竹、嘉兴雷竹、花哺鸡竹、乌哺鸡竹、红竹等6种为主,竹林面积占总面积的95%以上。从1987年到1990年通过调整结构,改善生长条件,完善采收技术等措施,建立了一个31.12亩丰产样板竹林。平均亩产、最高亩产分别为548.7 kg和1121 kg,亩均产较改造前和对照平均增加5倍。样板林经济效益显著,投入与产出之比达1:9.88。 相似文献
58.
浅析竹类植物的城市生态环境效应 总被引:11,自引:0,他引:11
竹子具有显著的生态效应,在生态建设中发挥着巨大的作用。在总结有关竹类植物生态效应研究成果的基础上,针对现代城市环境特点,着重分析竹类植物对城市环境的生态作用,指出在城市生态环境建设中应重视竹类植物的运用及其生态功能的持续有效发挥。 相似文献
59.
As a new use of bamboo, bamboo cubes may be useful as a shot-blast material for surface treatments. However, a suitable processing
technique for bamboo cubes has not been established. In this study, to obtain basic knowledge regarding the processing technology
for bamboo cubes, we installed shearing blades (upper and lower blades) in a universal testing machine to test cross-sectional
shearing of bamboo. The shearing force generated in this shearing was composed of a vertical component (F
v), a forward component (F
f), and a side component (F
s). This shearing force (F
v, F
f, and F
s) and the machining accuracy were investigated under various processing conditions. The shearing force became larger as the
thickness of bamboo increased. In particular, F
v showed a tendency to increase rapidly. Changes in the shear angle of the upper blade had a remarkable influence on F
v. This result suggests that the shearing force could be greatly decreased by adjusting the shear angle. The shearing force
within bamboo of 3mm in thickness was almost unaffected by the blade angle, and the change of shearing force with increasing
clearance was almost indiscernible. It was clearly demonstrated that a large number of bamboo cubes could be made when the
shear angle was large and cross-sectional shearing was performed from the bark side. However, a consequence of a large shear
angle is that burr area increases.
Part of this article was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003 相似文献
60.