改性脲醛树脂胶玉米秸秆皮碎料板的制备工艺     

张红杰  张显权  卢杰 《东北林业大学学报》2012,40(6):99-101

研究了玉米秸秆的结构及组成、玉米秸秆中皮、瓤、叶各部分所占的比例及皮与瓤的化学组成,分析探讨了合理的玉米秸秆的皮、瓤、叶分离工艺,对分离后玉米秸秆皮原料的加工处理工艺进行了探索。为确定改性脲醛树脂胶玉米秸秆皮板的制板工艺,通过正交试验对比分析了4个因素(热压时间、热压温度、密度和施胶量)对碎料板性能指标的影响,确定较佳的玉米秸秆皮板生产工艺为:热压温度155℃、热压时间4 min(板厚度10mm)、施胶量12%、密度为0.7 g/m3。  相似文献   

一种适合杨树树皮的蛋白质提取方法     

赵相涛  吕全  赵嘉平  马跃  陈亮  刘会香  张星耀 《山东农业科学》2012,44(7):121-123

双向电泳技术是进行蛋白质组分分离和功能鉴定的重要步骤。提取和制备高质量的蛋白质是进行双向电泳的首要前提。杨树树皮组织中含有大量的干扰物质,影响了蛋白质的提取和双向电泳的分离效果。为建立一种适合杨树树皮蛋白质的双向电泳程序,本实验以107杨为材料,采用改良的三氯乙酸-丙酮沉淀法提取杨树树皮蛋白质,经双向电泳和考马斯亮蓝染色检测,得到了理想的双向电泳图谱,为杨树与病原互作的蛋白质组学研究奠定了基础。  相似文献   

山白兰树皮率、心材率及木材密度研究     

苏勇  符韵林  廖克波  韦鹏练  徐同波  冯永敏  邓洪金 《西北林学院学报》2012,(2):249-252

采用排水法、体积法及质量法测定了山白兰树的密度、树皮率、生材体积和树皮率。结果表明:山白兰生材密度从髓心向外呈先减少,随后略增加的趋势,随着树高的增加,生材密度减小,生材密度的平均值为0.864g.cm-3;基本密度自髓心向外呈增大趋势,随着树高增加,基本密度减小,基本密度的平均值为0.462g.cm-3;生材含水率从髓心向外呈减小的趋势,随着树高的增加,生材含水率先增加后减小,生材含水率的平均值为89.0%;树皮体积百分率及质量百分率均随着树高的增加而增加,树皮体积百分率及质量百分率平均值分别为16.2%、20.4%;心材率随着树高的增加而减少,心材百分率平均值为16.3%。  相似文献   

白桦树皮提取物的降血脂作用研究     

左红香  郑光浩 《吉林林学院学报》2012,(1):65-67

目的研究白桦树皮提取物（BH）的降血脂作用．方法分正常组、模型组、BH给药组：高（300mg／kg）、中（200mg／kg）、低（100mg／kg）剂量和阳性对照组：脂必妥（300mg／kg）．预防给药7d,末次给药2h后,腹腔注射75％蛋黄乳液制作小鼠高脂血症模型,造模12h后测定不同剂量的BH对小鼠血脂水平的影响．结果白桦树皮提取物能够显著降低小鼠血清中TC,TG,LDL-C浓度,显著升高HDL-C．结论白桦树皮提取物具有明显的降血脂作用．  相似文献   

The complex symbiotic relationships of bark beetles with microorganisms: a potential practical approach for biological control in forestry     

Popa V  Déziel E  Lavallée R  Bauce E  Guertin C 《Pest management science》2012,68(7):963-975

Bark beetles, especially Dendroctonus species, are considered to be serious pests of the coniferous forests in North America. Bark beetle forest pests undergo population eruptions, causing region wide economic losses. In order to save forests, finding new and innovative environmentally friendly approaches in wood-boring insect pest management is more important than ever. Several biological control methods have been attempted over time to limit the damage and spreading of bark beetle epidemics. The use of entomopathogenic microorganisms against bark beetle populations is an attractive alternative tool for many biological control programmes in forestry. However, the effectiveness of these biological control agents is strongly affected by environmental factors, as well as by the susceptibility of the insect host. Bark beetle susceptibility to entomopathogens varies greatly between species. According to recent literature, bark beetles are engaged in symbiotic relationships with fungi and bacteria. These types of relationship are very complex and apparently involved in bark beetle defensive mechanisms against pathogens. The latest scientific discoveries in multipartite symbiosis have unravelled unexpected opportunities in bark beetle pest management, which are discussed in this article.  相似文献   

小蠹虫肠道中纤维素降解菌的分离及其产酶性质     

康柳  熊智  杜健伟  刘绍雄  朱丽丽 《西南林业大学学报》2012,(2):7-10

从小蠹虫幼虫肠道中筛选分离出降解纤维素的菌株5株,通过杜氏纤维素选择性培养基,以滤纸、脱脂棉和羧甲基纤维素钠为底物,测定菌株所产纤维素酶的活力。结果表明:酶活最强的为HS-11-5号菌株,最大酶活32.62 U/mL;此菌株的最佳产酶条件为:培养发酵时间50 h,培养所需最佳氮源为硫酸铵,培养最佳pH 7.5～8.5,培养最适温度28～30℃,最佳瓶装量为占培养瓶容积的12%～16%。  相似文献   

Energy wood resources availability and delivery cost in Northwest Russia     

《Scandinavian Journal of Forest Research》2012,27(7):689-700

Availability of solid by-products from wood harvesting and mechanical wood processing was estimated as sources for energy production based on recent actual harvesting, sawmill, and plywood production in Northwest Russia at 30 million m³. Nearly 70% of the energy wood, 20 million m³, was from harvesting, consisting of non-industrial round wood, unused branches and tops, defective wood resulting from logging, and spruce stumps removed after final felling. Over 30%, 10 million m³, of the available volume was from sawmills and plywood mills, i.e. wood chips, sawdust, and bark. Due to current low utilization of energy wood for bioenergy in Northwest Russia, delivery cost of energy wood to the potential border-crossing points in Finland was analyzed for three means of transport: railways, roadways, and waterways. Nearly 28 million m³ of the energy wood could be transported by railways and 2 million m³ by roadways and waterways. The costs were lowest by roadways from the nearby border areas (10–15 €/m³ for wood processing by-products and 16–22 €/m³ for forest chips). The costs by railways varied from 12 to 27 €/m³ on shorter distances to 47–58 €/m³ on longer distances. Waterway transportation was the most expensive, about 28–48 €/m³. It should be emphasized that we have estimated availability and delivery costs of energy wood, not prices which are defined by the market based on supply and demand.  相似文献   

Detecting spruce and fir log diameter under bark by using shape and image data     

《Scandinavian Journal of Forest Research》2012,27(5):440-448

The sawmilling industry stores and measures logs in bark in order to maximise efficiency, quality conservation and preservation. Billing is based on the diameter under bark, estimated based on manual or automatic bark detection. Although an automatic system is desirable for the industry, existing systems like tracheid effect scanners, X-ray or computed tomography either do not work reliably during all seasons or are very cost-intensive. This paper presents an approach for automatic determination of diameter under bark based on a multi-sensor approach including shape data, colour image data and tracheid effect data using laser scanning. For 686 spruce (Picea abies) and 79 fir (Abies alba) logs, diameters under bark are estimated and compared to the diameter after machine debarking. Estimation errors are close to zero and are below ±10 mm for more than 94% of the logs. Influences of season or characteristics like bark beetle are small. Specialised algorithms for diameter estimation in the presence of snow or bark beetle might further improve the result at the cost of required extra manual input.  相似文献   

Resin Tapping and Forest Cooperatives in Honduras     

《Journal of Sustainable Forestry》2013,32(3-4):135-169

Abstract

Case studies were completed on five Honduran agro-forestry cooperatives. A comparative instrumental analysis of the five case studies was utilized to determine the factors most important for success or failure of a cooperative. The case studies yielded ten focus areas of importance: forest resource base, land tenure, structure and governance, benefits for cooperative members and communities, institutional support, international aid projects, pine bark beetle, resin tapping, logging and marketing, and integration of logging and resin tapping.  相似文献   

不同粒径的桉树皮基质对桉树苗木的影响     

张沛健  谢耀坚  尚秀华  彭彦  方良  张国武 《桉树科技》2013,(4):25-28

以桉树皮为材料,通过对3种粒径桉树皮基质理化性质分析和苗木调查,研究不同粒径对基质理化性能和育苗效果的影响。试验结果表明：在育苗过程中,粒径〈2mm的桉树皮基质理化性质相对更稳定,苗木生长量最大,育苗效果最好;粒径2～5mm和5～10mm的桉树皮基质理化性质变化较明显,而粒径5～10mm的基质孔隙性变化最大,化学性质不够稳定,粒径对育苗基质和育苗效果影响较大。  相似文献