Effect of maleic anhydride grafted styrene-ethylene-butylene-styrene （MA-SEBS） on impact fracture behavior of polypropylene / wood fiber composites

MA-SEBS as compatibilizer and impact modifier was incorporated into Polypropylene/Wood Fiber （PP/WF） to enhance interface adhesion and impact strength of the composite. The effect of MA-SEBS content on the impact fracture behavior of PP/WF composites was studied. The impact properties of composites with 8% MA-SEBS reached the maximum value. And further increasing of MA-SEBS content to 10% did not improve the fracture toughness, but improved the stiffness of composites by DMA analysis. This was attributed to the improved PP/WF adhesion. As the MA-SEBS content is more than 8%, the molecule interaction of PP and WF was expected to much stronger than lower MA-SEBS. Scanning electron microscopy （SEM） was performed to analyze the impact fracture surface and showed a stronger affinity for the wood surfaces.     

林火对森林虫害发生影响的研究

对黑龙江省的大兴安岭、黑河、伊春、牡丹江等林区近5年的火灾过火林地进行森林虫害调查分析.结果表明:大兴安岭及黑河林区森林过火后主要虫害为天牛和小蠹类;伊春林区食叶害虫种类较多,但危害较轻;牡丹江林区落叶松毛虫发生程度严重.森林火灾后林内蛀干害虫大量发生,树干熏黑高度是影响虫害发生数量的一个重要因子.火烧强度与虫害发生数量呈正相关性;天牛及小蠹类虫害发生数量与树干熏黑高度线性关系明显;兴安落叶松林、樟子松林、白桦林的虫害发生数量与树干熏黑高度相关性较高,兴安落叶松和樟子松林尤为明显.     

二灰碎石半刚性基层沥青路面横裂缝起因的探讨

本文针对在施工中混凝土路面出现的干缩裂缝、横向断板及纵向断板产生的原因进行分析,并提出了相应的预防措施。     

姬松茸固体饮料的研究

姬松茸是一种正待开发的药食兼用真菌,因其含有抗肿瘤活性多糖而备受关注。利用现代食品工程高新技术———超微粉技术将姬松茸子实体粉碎,使其组织细胞高度破坏,提高了多糖的溶出率。通过正交实验确定姬松茸固体饮料配方为蔗糖量10%,柠檬酸,糖酸比为33.3∶1。     

火棘种子油理化特性研究初报

陕西杨凌人工栽植的火棘，种子含油率为１３．７８％，种子油的酸值，碘值及皂化值分别为３．５、１４５．３，１８９．３，所含的６种脂肪酸及其比率为软脂酸１３．１５５％。硬脂酸０．８２１％，油酸１１．９７０％，亚油酸７２．７１９％，亚麻酸１．０８８％，芥酸０．１６６％，火棘种子油中的脂肪酸种类和组成与名贵的食用营养油－红花籽油相近，其突出特点在于亚油酸含量极高，很有开发利用前景。     

陕北黄土区小檗属植物资源调查与播种育苗试验

经调查,陕北黄土区小哭属(Berberis)植物资源有6种,蕴藏量3000担左右。可分为抗旱、中生和湿生3种生态类型。播种育苗试验,种子沙藏处理比热水浸种和干播,平均出苗率分别提高9%和15%,平均提前5天、10天。     

粤西乐昌含笑种源试验分析*

以大坑山林场乐昌含笑种源试验林7年生观测数据作遗传变异分析,表型变异分析结果表明树高、胸径、材积、树干通直度、叶片大小、树冠浓密度和冠幅等7个性状种源间都存在较大的差异;方差分析结果表明大部分性状种源间差异达极显著或显著水平;遗传参数估计结果表明生长性状的种源遗传力处于中等偏下水平,形质性状处于中等水平,材积的遗传变异系数最大;根据多重比较结果,以材积为选择目标,选出6个速生种源,增益介于11.1%～35.1%之间。粤西乐昌含笑优良种源主要集中在广东和江西交界的多个县市。     

Dynamics of Zn between soil and plant in Northeast Leymus chinensis grassland

A study was conducted to determine the dynamic of Zn content between soil and plant in the natural protection zone of Leymus chinensis grassland in Changling County (44°30′–44°45′N; 123°31′–124°10′E), Jilin Province, China. Results showed that the total Zn content was lower, available Zn content had a moderate level in the soil, and the plants was not lack of Zn. During the growing season, content of total Zn and available Zn in soil showed a down-trend distribution along the soil profile. Content of total Zn had a significantly positive correlation with that of the organic matter, but it was negatively correlated to soil pH. Monthly dynamic of the average content of total Zn showed a “V” type curve in the growing season from May to August, and July was the nadir. The trend of the average content of available Zn was similar to the content of total Zn, but was down after August; Zn content variation in the organs and litter of L. chinensis was great, with the order of root>rhizome >leaf>stem>litter. The ratio of available Zn content in A layer versus B layer was more than 2 times that of the total Zn, which indicated that the soil of A layer had higher enrichment capacity of available Zn. The enrichment of Zn in the root of L. chinensis was 44.17 times as that in the soil. The absorbing intensity of root had a significantly negative correlation with the activity of Zn in the soil (r=−0.8800, p<0.01). Biography: ZHOU Xiao-mei (1966–), female, Ph.D., associate professor of Jilin Normal University, Siping 136000, P.R. China.     

气候因子对木材特性影响的研究进展

对国内外在木材学、气象学、植物学等领域内有关气候因子对木材特性影响的研究现状进行了总结和分析，阐述了进行气候因子对木材特性的影响研究的重要意义；光照因子、温度因子、湿度因子、降水因子以及自然灾害对木材特性的影响规律；气候因子对木材特性影响的研究方法；同时展望了气候因子对木材特性影响研究的发展方向。     

杉木、马尾松裸根苗水分关系研究

Water relation parameters of bare-root seedlings of Chinese fir (Cunninghamia lanceolata Hook.)and Masson pine (Pinus massoniana Lamb.)were measured and changes of root growth potential as well as field survival rate of both species were studied after the bare-root seedlings were exposed in a sunny field condition.the results showed that masson pine had a lower osmotic potential(-2.07Mpa) at turgor loss point and at full turgor(-1.29Mpa),compared with Chinese fir(-1.80Mpa and -1.08Mpa respectively).The parameter Vp/Vo(63.27%) of Masson pine was higher than that of chinese fir (58.03%).This means that Masson pine has a stronger ability to tolerate desiccation,compared to Chinese fir according to analysis of above water relation parameters.Root growth potential and field survival rate decreased with prolonging duration of exposure.The field survival rate of both species was reduced to less than 40% after the seedling being exposed only two hours.Water potentials of -1.60 Mpa and -1.70 Mpa were suggested to be critical values for Chinese fir and Masson pine respectively in successful reforestation.