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Diversity of Plant Species of Alpine Grassland in Nakchu of Tibet, China 被引量:2
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作者 YANYan ZENGYun-ying +2 位作者 ZHANGJian-hui ZHANGJian-guo zhong-xiang-hao 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第4期659-664,共6页
Characteristics of plant species diversity of two types of grassland communities (alpine meadow and alpine grassland) was examined and the relationship between species diversity and community dynamics was determined u... Characteristics of plant species diversity of two types of grassland communities (alpine meadow and alpine grassland) was examined and the relationship between species diversity and community dynamics was determined using GPS positioning and in situscrutinization of community of alpine grassland in Nakchu prefecture of Tibet Autonomous Region. The result indicated that: ① there was an unobvious difference between grassland communities in terms of richness index of plant, evenness index, dominant index and diversity index. The species diversity index followed the order Kobresia humilis meadow >Stipa purpurea steppe>K. littledalei meadow; ② the original community created high diversity, while the degenerative community suffering from serious disturbance was of low diversity; ③ the diversity of community plants was closely related to changes of species biomass, and the growth and decline of species in the community; ④ grazing disturbance is a key factor of community dynamics, leading to coexistence of various secondary successions of communities, diversified suitable habitats and species diversity. improvements 展开更多
关键词 alpine grassland species diversity human activity TIBET
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断带抓捕器仿生抓捕靴表面增摩机理分析 被引量:1
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作者 周满山 李忠祥 +3 位作者 张媛 郝妮妮 赵士英 谭文涛 《煤矿机械》 2017年第9期56-58,共3页
在研究断带抓捕器抓捕稳定性的过程中,分析了断带抓捕器的性能要求。根据全断面断带抓捕器的抓捕过程和抓捕原理,确定了抓捕靴表面的摩擦系数对抓捕器抓捕稳定性的影响。分别描述了普通抓捕靴表面和仿生抓捕靴表面与输送带接触时接触面... 在研究断带抓捕器抓捕稳定性的过程中,分析了断带抓捕器的性能要求。根据全断面断带抓捕器的抓捕过程和抓捕原理,确定了抓捕靴表面的摩擦系数对抓捕器抓捕稳定性的影响。分别描述了普通抓捕靴表面和仿生抓捕靴表面与输送带接触时接触面上输送带的流动状态,并利用ANSYS软件对凸起刚性体与柔性体接触行为进行仿真。分析了仿生抓捕靴表面增摩机理,推导了仿生抓捕靴与输送带之间的摩擦系数及摩擦力的表达式。 展开更多
关键词 仿生摩擦学 断带抓捕器 仿生抓捕靴 增摩机理
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