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1.
竹/玻璃钢复合建筑材料是一种新型三维复合材料.本文对其进行了结构设计的研究,并通过大量试验对其力学性能进行了分析,结果证明竹/玻璃钢复合建筑材料确实是一种重量轻、性能好、工艺简单、价格便宜的材料,具有广阔的应用前景.  相似文献   
2.
竹纤维素的结构表征   总被引:5,自引:1,他引:5  
对纺织用竹纤维、黏胶用竹浆粕、造纸用竹浆粕、高级竹浆粕进行物化性能分析,并对其结构进行表征。显微镜观察显示,竹纤维纵向表面有竹节,相比纺织用竹纤维光滑的表面,竹浆粕呈现明显的微纤结构;由X-衍射(WAXD)分析结果可知,纺织用竹纤维结晶属于典型的纤维素Ⅰ,内部具有完善的微纤结构,结晶度和晶粒尺寸均明显高于三种竹浆粕,主要原因是分子间具有更强的氢键作用。  相似文献   
3.
竹材丙酮法木质素高效分离技术研究   总被引:6,自引:1,他引:6  
在一定的温度、压力条件下,利用丙酮提取竹材中的木质素,丙酮通过蒸馏回收后,可以反复利用;而通过蒸馏,得到的高纯度的木质素是重要的化工原料,整个过程形成一个封闭循环系统,基本上无三废排放;研究结果表明:当丙酮浓度为80%,液固比为10∶1,在最高反应温度160℃下保温3h,降解木质素的效果最佳;为解决制浆造纸行业废水对环境的污染问题提出了一条新的途径。  相似文献   
4.
采用离子交联法,以高纯竹叶碳苷黄酮制剂(碳苷总质量分数﹥90%,记为H-BLF)和芫根阴离子多糖(TP)为原料,通过ε-聚赖氨酸(ε-PL)的阳离子桥键合而成竹叶碳苷黄酮纳米混悬液(H-BLFnd),进一步在混悬液中添加8%(w/v)的γ-环糊精、经真空冷冻干燥得到纳米冻干粉(H-BLFnp),采用粒径分析、TEM、UV、FTIR、TG和DSC对其外观、性能、结构进行表征。结果表明: H-BLFnp外观为白色粉状,表面光洁平整,色泽均匀,平均粒径为(679±10.2)nm,分散系数为(0.349±0.004),包埋率为(92.39±0.34)%。  相似文献   
5.
Composites of unplasticized poly(vinyl chloride) (PVC) blended with bamboo flour and pine flour, respectively, were prepared in a batch mixer followed by compression molding. The effects of wood flour fillers on the morphology, static mechanical properties, and thermal properties of the composites were investigated. Compared with neat PVC resin, the introduction of both bamboo flour and pine flour significantly improved the stiffness of the composites, while decreasing the tensile strength to some extent. Tensile tests showed that pine flour–filled composites exhibited better mechanical properties than those filled with bamboo flour with the same particle size at the same loading level. Scanning electron microscopic examination revealed good dispersion and alignment tendency of short pine fiber within the composites at a lower loading level. Moreover, experimental results indicated that both bamboo flour and pine flour additions showed no obviously adverse effect on the thermal stabilities of these composites. Based on the comprehensive properties, these composites meet the need of woodlike material for use as wood structures. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1804–1811, 2004  相似文献   
6.
采用80S丝光羊毛纤维和3D毛型竹浆纤维混纺纱,混纺比例竹浆/丝光羊毛分别为30/70、50/50、70/30,进行针织物开发及舒适性探究。通过对混纺纱的强力、伸长率、耐磨性及毛羽进行测试,得出:实验结果均满足上机织造标准。以纬平针组织为例,织造出三种混纺比针织物,并对其透气性、透湿性和热导率进行了测试分析,实验结果表明:织物透气性、热导率随丝光羊毛含量的增加而降低,透湿量随之增加。  相似文献   
7.
A new type of bamboo biochar (BC) loaded TiO2-SnO2 particle electrode was prepared and characterized by SEM, FT-IR, BET and XRD for efficient treatment of the coking wastewater in a three-dimensional electrochemical reaction system(3DERs). The results showed that bamboo biochar had a dense microporous space structure, and a significant amount of Ti-Sn oxides existed on the surface and in the interior of the BC. The removal rates of COD and DOC in coking wastewater reached to 73.96% and 66.72% respectively, and UV254 reduced from 6.65 cm-1 to 3.00 cm-1 by the electrolysis treatment of 150 min at the current density of 30 mA/cm2. The three-dimensional fluorescence spectra indicated that the most of the soluble organic compounds and soluble microbial by-products were degraded and transformed. The addition of Ti and Sn enhanced the efficacy of the electrooxidation, electro-adsorption and electrocatalytic behavior of the BC particle electrodes, which improved the treatment effect on coking wastewater in the 3DERs. In addition, this study provides the possibility of basic research for the engineering practice of electrochemical oxidation treatment of coking wastewater.  相似文献   
8.
9.
英国学者李约瑟在深入研究中国科技史后认为,东亚文明乃是"竹子文明,中国人民的血液里流着竹子的文化"。我国不仅竹资源丰富,更是在竹资源的开发与利用上历史最为悠久的国家。我国南方有着大面积的竹产地,竹子及竹制品对当地的社会经济、民俗文化都有很大的影响。如何对"竹"这一传统材料进行创新性的开发和利用,最大限度的实现竹自身的价值,使制竹产业焕发出新的活力,成为当前研究的主要问题。  相似文献   
10.
Thermal and moisture characteristics of the bamboo structure wall were tested in natural climate and three representative variation processes of heat and moisture: heating from solar radiation in summer at normal temperature and humidity, heating from solar radiation in summer at normal temperature and high humidity after rain, humidifying from brash in summer at high temperature and normal humidity. The results show that, in summer, the largest temperature difference between external and internal surface of the 28 mm-thick bamboo plywood wall is 11.73 °C (at 15:40) and the largest strain difference is 136 μm/m (at 18:50), both in ambient and indoor conditioned environment. In heating process, lengthways of the wall surface are in contracting strain while transverse ways are in expanding strain at initial stage and in contracting strain during later period. When the high temperature wall is humidified by rain, the surface temperature drops, moisture content increases and the expanding strain is presented on the surface during the whole process. Temperature and moisture content are two important factors which affect thermal and moisture stress (TMS) of the bamboo structure wall. The TMS is not only related to temperature and moisture content, but also greatly affected by temperature gradient, moisture content gradient and rates of changing.  相似文献   
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