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首次研究了国产湿地松及云南松树皮单宁的化学组成。二者均为聚合的原花青定。在组成单元中,前者以2,3-顺式为主,后者含2,3-反式单元较多。对单宁的分子量,甲醛值及凝胶时间也做了探讨。  相似文献   
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The present article deals with the use of tree barks as a natural trap for airborne spores and pollen grains in China. The study carried out at the southern part of Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences has yielded a variety of palynomorphs mostly belonging to tree taxa. New methodologies for extraction of palynomorphs from tree barks have been suggested. Bark samples were collected from three taxa, i.e., Paulownia fortunei Hemsl. (Scrophulariaceae), Quercus dentata Thunb. (Fagaceae), and Picea meyeri Rehder & E.H. Wilson (Pinaceae) having different bark morphologies. P. fortunei with a comparatively soft and fissured bark is believed to have a greater potential for trapping airborne spores and pollen grains compared to the stiff and less fissured barks of Q. dentata and the scaly bark of P. meyeri. Old barks yield better data in terms of quantity and quality of trapped pollen and spores. The present study throws new light on the modern pollen rain, spore-pollen dispersal, and their deposition in and aroundBeijing Botanical Garden, and other different parts of China.  相似文献   
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