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91.
微米木纤维形成MFB的初探 总被引:15,自引:0,他引:15
提出了一种新板种MFB的制备方法。MFB由特殊的构成单元组成,该构成单元系根据细胞破碎理论采用微切削工艺制得,其厚度达到微米级水平。根据其方法在实验室制得的MFB样品的弹性模量达5171MPa,握钉力达1933N。MFB具有很多优点:具有木本色、美感、保温、绿色消费、寿命高、没有节子一类缺陷、防止变形等,所以可得到广泛的应用,其发展前景良好。笔者认为,MFB板种的提出是对人造板的发展做出了贡献。 相似文献
92.
防霉中密度纤维板的研制 总被引:1,自引:0,他引:1
在湿度较大的地区和潮湿的场所,中密度纤维板(下称中纤板)因长期受潮而产生霉变,使其性能受损,更为严重的是污染了居住环境。因此,研究如何防止中纤板霉变,使其具有防霉性能应作为一项重要的课题。笔者通过对防霉剂选择、优化热压工艺参数、防霉效果测试等方面进行了试验研究,确定了适当的防霉剂及其添加量,得出了压制防霉中纤板的优化热压工艺。 相似文献
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对竹基纤维复合材料进行两种条件(80℃处理8h和50℃处理24 h)的热固化处理后,观测其表观形貌,并进行拉伸、压缩、水平剪切性能以及疲劳性能检测.结果表明:经过热固化处理后,竹基纤维复合材料表面有不连续的微小裂纹产生,其拉伸、压缩、水平剪切性能略有提高,疲劳性能则无显著变化. 相似文献
95.
为了考察碱/炭比、炭化温度以及活化温度对活性炭纤维孔结构的影响,以木粉为原料经液化、纺丝、固化、炭化及KOH活化工艺过程制备了木材苯酚液化物活性炭纤维;采用正交实验方法优化了活性炭纤维制备工艺。结果表明:诸因素中的显著性依次为活化温度〉炭化温度〉碱/炭比;优化组活性炭纤维的比表面积为1546m^2/g;400℃炭化温度下制备的活性炭纤维具有较高的中孔比率。 相似文献
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To obtain a better understanding of variability in wood properties along the stem in triploid hybrids of Populus tomentosa L., basic wood density (BWD) and fiber traits were measured at four sample heights for each tree sampled from three clonal trials. The BWD showed a similar trend at each site in that density was initially decreased then increased with increasing height position. For fiber traits, the fiber length (FL) decreased linearly with the height of the trunk, whereas fiber width and coarseness changed relatively slightly with increasing height position. In addition, the vertical wood properties distribution patterns were different from clones so that some clones showed more markedly change in height positions than others. The joint analysis indicated significant height position effect for BWD and fiber traits, in accordance with site and clonal effect. Significant site × height interaction was found on wood properties, whereas the significant clone × height interaction was only obtained at fiber width. Moreover, variation in the relationships between FL and BWD or other fiber traits showed no consistent pattern with increasing height position. 相似文献
99.
Research on the mechanical amplification function of natural organisms presents a bio-inspired approach for the future design of strain sensors to be embedded in engineering bodies. By the observation under FTEM, the micromorphology of chafer cuticle is found as follows:insect cuticle is a typical example of a natural composite plate with cross-fiber laminates reinforced,on the surface of which a series of trichopores with diameter of 50~70 μm are distributed in the space of 40~50 μm. This microstructure is characterized as a composite plate with holes with cross-fiber laminates reinforced. The stress amplification factor that helps to improve sensilla’s sensitivity is achieved as 2.424 by finite element method and weighted average method. Furthermore continuous helicoidal fibers around the channel under trichopore are found,which resist stress concentration from every orientation and protect the gland and body wall. 相似文献
100.
Ha Duy Truong Chong Ho Wang Tran Trung Kien 《Communications in Soil Science and Plant Analysis》2017,48(14):1701-1709
This research was conducted to investigate the effects of different medium compositions on physicochemical properties and the growth of two tomato varieties. Five treatments were applied, combining medium composition with rice husk ash (RHS) and coconut fiber (CF) with the following proportions: 1/3 Peat moss + 1/3 rice husk ash + 1/3 coconut fiber (T1); 1/3 Vermicompost + 1/3 rice husk ash + 1/3 coconut fiber (T2); 1/3 Cattle manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T3); 1/3 Chicken manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T4); 1/3 Hog manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T5). The results demonstrated that between pH, electrical conductivity (EC) value, and nutrient content in the media, there was a significant difference that led to different concentrations of total macro- and micronutrients in the shoots of both varieties. In addition, the root weight, shoot weight, and root volume were affected by medium composition for two varieties in seedling stage. A mixture of cattle manures composted with RHS and CF under the rate (1:1:1 by volume), respectively, gave the highest value of germination rate, plant height, leaf number, and plant biomass. Medium composition significantly influenced the germination rate and elongation of seedlings, specifically for each tomato variety. Therefore, cattle manure compost as a medium supplement improves seedling quality and growth of the two tomato varieties. 相似文献