首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到14条相似文献,搜索用时 562 毫秒
1.
利用3个22年生马尾松初级种子园自由授粉家系1.3 m、5.3 m和10.0 m 3个高度圆盘,研究3个家系纵向木材化学组分的变化规律。结果表明:综纤维、酸不溶木素、冷水抽提物、热水抽提物、苯醇抽提物、1%NaOH抽提物、灰分和水分等8个化学组分含量指标在树干纵向高度间差异显著。纤维素、综纤维、酸不溶木素、热水抽提物、苯醇抽提物、1%NaOH抽提物、灰分和水分等8个化学组分含量均随着树干高度的增加不断下降。混合取样数据接近整株化学组分的平均水平,因而宜采用混合样分析马尾松化学组分变化。不同家系木材化学组分的纵向均匀性以169号最好,159次之,162最差。  相似文献   

2.
杞柳的化学成分及其木质素微区分布的研究   总被引:1,自引:0,他引:1  
采用传统的化学成分测试方法和激光扫描共聚焦显微镜技术(CLSM)研究了杞柳的化学成分以及木质素在各细胞及纤维细胞各微区的分布,分析了株高不同部位化学成分的变异规律。结果表明:杞柳的1%Na OH抽提物、热水抽提物、冷水抽提物、苯醇抽提物、综纤维素、α-纤维素、酸不溶木质素、酸溶木质素、多戊糖和灰分分别为32.11%、10.85%、7.11%、3.27%、70.46%、35.50%、20.18%、4.50%、15.51%、0.90%;在不同部位,除了α-纤维素和多戊糖含量差异不显著,其余各指标均差异显著;木质素在各细胞及纤维细胞各微区分布不均一,导管细胞壁木质素浓度高于木纤维和射线,纤维细胞角隅处木质素浓度高于次生壁和复合胞间层。  相似文献   

3.
以6个22年生马尾松初级种子园半同胞家系为研究对象,比较优良家系、最差家系和对照的生长、单位面积材干物质产量及材性差异。结果表明,不同家系的单株材积、木材密度和木材干物质产量间差异显著;纤维素、综纤维、酸不溶木素、戊聚糖、冷水抽提物、热水抽提物、1%NaOH抽提物、苯醇抽提物、灰分和水分等10个化学组分的含量间差异不显著;单位面积木材干物质产量是马尾松材性改良的首选指标,木材化学组分可作为参考指标。  相似文献   

4.
黄藤藤材的化学组成特性   总被引:2,自引:0,他引:2  
黄藤的藤芯和藤皮组分有明显不同.与藤皮相比,藤芯的各种抽提物含量、聚戊糖含量、酸度、酸碱缓冲容量更大,综纤维素含量、木素含量、灰分含量和pH值等更小,阿拉伯糖和木糖等五碳糖的含量更低,而甘露糖、半乳糖和葡萄糖等六碳糖的含量更高,糖类组分的绝对含量更低.这说明藤芯含有更多的吸湿性基团、半纤维素和酸性物质等,含有更少的纤维素、木质素和灰分等.自藤茎基部向上,抽提物含量减少,酸度减小,聚戊糖含量增多,综纤维素含量、木素含量和灰分含量呈增多趋势但变化不大.与一般木、竹、藤材相比,黄藤藤材含抽提物较多,纤维素较少,酸度较大,酸碱冲容量较大;半纤维素以聚木糖为主.这些化学组成特征对黄藤藤材在制浆造纸等方面的应用是不利的.  相似文献   

5.
紫茎泽兰茎秆中的10种物质含量测定   总被引:2,自引:0,他引:2  
运用非木质造纸原料成分分析法对紫茎泽兰茎秆中的10种物质含量进行了测定。结果表明,其茎秆中水分含量为10.00%~11.60%,灰分含量为3.54%,冷水抽提物含量为28.25%,热水抽提物含量为32.40%,苯醇抽提物含量为12.50%,1%氢氧化钠抽提物含量为52.40%,酸不溶木素的含量为17.84%,聚戊糖的含量为13.14%,综纤维素含量为51.81%,纤维素含量为26.45%。与松树、玉米等木本和草本植物相比,紫茎泽兰与之有着类似的物质组成特征。  相似文献   

6.
火炬松纸浆材化学成分及其在树干高度上的变异规律   总被引:1,自引:1,他引:1  
对18年生人工林火炬松纸浆材的化学成分含量进行了系统地测试,分析和讨论了火炬松化学成分含量在树干高度方向上的变异规律.结果表明:1、火炬松纸浆材的灰分、冷水、热水、苯醇和1%N aOH抽提物含量,纤维素、戊聚糖和木质素含量平均值分别为0.33%、1.59%、3.21%、2.32%和13.66%、47.98%、15.10%、29.66%;2、沿树干高度方向,火炬松木材灰分含量和纤维素含量变化不明显;热水和苯醇抽提物含量逐渐减小;冷水抽提物和木质素含量表现出先增加后减小或者逐渐减小的趋势;1%N aOH抽提物含量则表现出先减小后增加的趋势;戊聚糖含量表现出逐渐增加或减小的趋势.方差分析表明,火炬松木材各化学成分含量在沿树干高度方向的变化不显著.  相似文献   

7.
采用我国木材化学成分分析国家标准,对人工林米老排木材化学成分进行了测定和研究分析.结果表明:人工林米老排木材冷水抽提物含量和热水抽提物含量分别为2.67%和3.12%,1%NaOH抽提物含量为17.08%,纤维素含量为47.49%,综纤维素含量为80.42%,木素含量为28.80%,pH值为5.44;木材冷水抽提物和综纤维素含量在树干的不同高度上略有差异,但方差分析检验,差异不显著,热水抽提物、1%NaOH抽提物、纤维素和木素含量在树干的不同高度上差异显著,达到1%显著性水平;由树基往上,热水抽提物含量略呈两端高、中间低的趋势,冷水抽提物、1%NaOH抽提物和木素的含量逐渐降低,综纤维素含量和木材pH值逐渐升高;纤维素含量在树干上的分布规律为中间高、两端低,而且从树干中部往上的降低幅度较大.  相似文献   

8.
研究我国黑木相思木材化学性质的株内变异规律,为其加工利用提供基础数据。对广东韶关产28 a黑木相思木材进行化学组成测定,其综纤维素(α纤维素、半纤维素)、酸不溶木质素和抽出物(冷水、热水、1%氢氧化钠、苯醇)的含量在株内纵向上的变异规律不明显;相较于边材,心材的综纤维素含量略低,酸不溶木质素含量略高,抽出物含量更高,pH值更低。实际加工利用中需考虑其心材和边材比例对原料化学组成的影响。  相似文献   

9.
选取不同树干高度的栓皮栎和麻栎木材,分别测定树皮、边材和心材的苯醇抽出物、综纤维素(α-纤纤维素和半纤维素)、木质素(酸不溶和酸溶木质素)、灰分、pH值和缓冲容量,为软木及栎木人造板的生产加工利用提供科学依据。栓皮栎软木生产工艺应关注树皮苯醇抽出物含量、灰分、pH值及缓冲容量;用于人造板加工,则需考虑树种及心边材纤维素、木质素和pH值。  相似文献   

10.
微波处理对木材化学组分含量影响的研究有助于了解木材微波处理机理。以樟子松为原料,使用隧道式微波设备处理木材,在试验条件下,木材中心最高温度可达183℃;微波功率密度和初含水率及二者的交互作用,对樟子松木材中三大素成分含量变化具有显著影响。处理后木质素相对含量增加,纤维素和半纤维素含量降幅小于5%;冷水抽提物、苯醇抽提物和1%NaOH抽提物含量降低;处理材pH值升高,但仍处于酸性范围;灰分含量保持不变。  相似文献   

11.
The objective of this study is to determine the properties of G. amplexifolia. In this paper; the chemical composition, including holocellulose, acid-insoluble lignin, 1% NaOH solubility, benzene-ethanol extractives and ash content, was considered for the variability with respect to positions along bamboo culm height (bottom, middle and top), parts along radial direction (inner part and outer part)and ages (1-year and 2- year). The test results were also compared to those of moso that is commonly planted and used in China. This study indicated that both the holocellulosecontent and the lignin content in inner part were lower than ; in outer part, but for extractives and ash content, the reverse was true. Bamboo age also had effect on chemical composition; both the holocellulose content and the ash content in the culm of 1- year were higher than those of 2-year; while the lignin content and the extractive content m the culm of 1- year were higher than those of 2-year. High holocellulose content, low lignin contentand extractive content were advantages of G. amplexifolia.  相似文献   

12.
Epidermal peeling (EPT) and steam-heating (SHT) treatments are two widely processing methods in bamboo industry. Moso bamboo (Phyllostachys pubescens Mazel) and makino bamboo (Phyllostachys makinoi Hayata) are important economical bamboo species in Taiwan and China. The subject of this study was to access the changes of chemical and mechanical properties in moso and makino bamboo culms, which were collected from Taiwan and China after EPT and SHT. As regard to chemical properties, the amounts of extractives and ash were increased both in moso and makino bamboos after EPT and SHT. In contrast, the contains of holocellulose and α-cellulose were decreased after EPT and SHT for two bamboos. Moso bamboo collected from China contained the lowest cellulose content but the highest amount of hemicellulose by SHT. The lignin contents of all samples were no significant different after SHT, and it might due to the structure of lignin did not destroy at 120 °C. For the mechanical properties, the density of all makino and moso bamboo samples was reduced after SHT; moreover, the decreasing trend of density was similar to the reducing of holocellulose, α-cellulose, hemicellulose, and equilibrium moisture content (EMC). All bamboo samples without EPT presented the highest modulus of elasticity (MOE) and modulus of rupture (MOR) whether SHT or not. Both MOE and MOR of all bamboo samples were decreased after SHT. The integrity of the bamboo skin is important for the dimensional stability of the bamboo, and the water absorption ability would be increased after EPT; however, SHT decreased the water absorption of bamboo.  相似文献   

13.
Use of butanol-water mixtures for making wheat straw pulp   总被引:1,自引:0,他引:1  
Summary A central composite design was used to investigate the influence of the cooking conditions (time, temperature and butanol concentration) for wheat straw with butanol-water mixtures on the properties of the pulp obtained (yield and holocellulose, α-cellulose, lignin and ethanol-benzene extractives contents) and the pH of the resulting waste water. A second-order polynomial model consisting of three independent process variables was found to accurately describe the organosolv pulping of wheat straw. The equations derived predict the yield, the holocellulose, α-cellulose, lignin and ethanol-benzene extractives contents of the pulp, and the pH of the waste water with multiple-R, R2, adjusted-R2 and Snedecor' F values of 0.99, 0.99, 0.99 and 310.33; 0.98, 0.97, 0.95 and 56.63; 0.91, 0.84, 0.74 and 9.14; 0.99, 0.98, 0.96 and 70.52; 0.97, 0.94, 0.92 and 40.42; and 0.98, 0.95, 0.93 and 49.33, respectively. The process variables must be set at low values in order to ensure a high yield and pH. On the other hand, if a high holocellulose content and low lignin and ethanol-benzene extractives contents are to be obtained, then the process variables must be set at high values. Finally, obtaining pulp with a high α-cellulose content entails using a long cooking time and a high temperature, as well as a low butanol concentration. Received 1 July 1996  相似文献   

14.
巨龙竹是至目前为止所发现最粗的竹子,单株竹材生物量居同类竹材之首。对3-5年生薄壁型巨龙竹秆材不同部位的主要化学成分进行了测定,包括灰分、木素、综纤维素、多戊糖、冷水抽出物、热水抽出物、1%Na OH抽出物、乙醚抽出物、苯-醇抽出物。结果表明:薄壁型巨龙竹的木素、综纤维素、多戊糖的含量与常用纸浆造纸原料木材接近,灰分含量介于木材和草类原料之间;除冷水抽出物外,薄壁型巨龙竹其它抽出物含量在秆高方向上均表现出递增的分布规律。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号