Papers by Keyword: Plaque

Paper TitlePage

Authors: Sung Min Kim, Sung Yun Park
Abstract: In this paper, non-linear interactions between a stent and an artery are analyzed using the finite element method [ANSYS (Ver 10.0)]. The material property of the artery is assumed to be hyper-elastic. The loading conditions were applied in three steps, according to the pressure level (pressure increase, constant load pressure, and pressure decrease). From the results, the maximum von Mises stresses were measured in the area of contact of the stent and the artery. The maximum von Mises stresses of the stent and artery were obtained and the increase in the maximum pressure showed a decrease in the von Mises stress of the stent. The simulated results show that the distal end of the stent, which tilted after the expansion behavior in the artery, may damage the artery wall. The finite element model used in this study may help in designing the stent.
Authors: Yu Jia Song, Hui Qing Liu
Abstract: Set 5 sample sections in a certain gully area in the tributary of Iton River from upstream to downstream of Changchun city, which locates in the northern part of China, then respectively collect sediments and soils which are proximal and distal away from the river bank, test the heavy metal content of Zn, Cu, Cd, Pb and conduct pollution assessment. The result shows that: the content of Zn in sediment is in the state of light pollution, Cu has an obvious accumulated tendency, Pb,Cd are basically in a state of local background value. Therefore, the pollution index of sediment is in a state of slightly pollution, the proximal bank-side is in the safe state, while the distal bank-side is in a state of alert. The main reasons that cause heavy metals pollution and accumulation are traffic and agricultural pollutions.
Authors: Yu Jia Song, Hui Qing Liu
Abstract: The discharge of urban sewage and agricultural non-point source pollutants is the main reason causing eutrophication in gullies in most cities of northern China. Based on a careful analysis on the ecological structure and ecological characteristics of a gully, this article preliminarily studies the interception and degradation mechanisms of nitrogen pollutants by the gully. Meanwhile, to take gullies in Changchun as the object of the study, this article carries out an experiment on the interception effect of nitrogen pollutants by gullies. This experiment respectively establishes a control section in the upper and lower reaches of a gully, and takes water samples four times in each section from May to August to determine total nitrogen, total phosphorus, nitrate nitrogen, ammonia nitrogen and salinity. The result shows: the gully plays some role in the interception of pollutants; total phosphorus accounts for the largest interception in pollutants in the experimented gully section, with the relative interception rate of 27.46%, followed by ammonia nitrogen, with the interception rate of 21.80%, which is the result of the combined effects of aquatic plants, microorganisms and sediment in the gully.
Showing 1 to 4 of 4 Paper Titles