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食用蔬菜能吸收和积累微塑料 期刊论文  OAI收割
科学通报, 2019, 卷号: 64, 期号: 9, 页码: 928-934
作者:  
李连祯;  周倩;  尹娜;  涂晨;  骆永明
  |  收藏  |  浏览/下载:154/0  |  提交时间:2020/06/17
微塑料  生菜  聚苯乙烯微球  吸收  积累  健康风险  microplastics  lettuce  polystyrene microbeads  uptake  accumulation  human health risk  Microplastic (MP, 100 nm-5 mm) may present an attributable risk to ecosystem and human health, and its pollution has become a global environmental concern. Despite a wealth of information on the accumulation of MPs in aquatic species, there is no information on the uptake and accumulation of MPs by higher plants. Terrestrial edible plants are directly exposed to MPs when agricultural soil was applied with organic manure, sewage sludge as fertilizer or plastic mulching. In this paper, the uptake of two sizes of polystyrene (PS) microbeads (0.2 and 1.0 mum) and then their distribution and migration in an edible plant lettuce were firstly investigated based on laboratory experiments. We used fluorescent markers to track PS microbeads in plant tissues and found fluorescence to be a sensitive and reliable detection method. Sections from untreated control lettuce showed no autofluorescence. When roots were treated with fluorescently labeled PS microbeads, the microbeads could be identified by its fluorescence. Our main study investigated the uptake of 0.2 mum beads, as few luminescence signals were observed in lettuce roots for 1.0 mum beads in our experiment. We observed that 0.2 mum fluorescent microbeads were extracellularly trapped in the root cap mucilage (which is a highly hydrated polysaccharide) and a dark green tip (which was typical of lettuce roots exposed to label PS beads) was usually visible to the naked eye. Confocal images revealed that the PS luminescence signals were mainly located in the vascular system and on the cell walls of the cortex tissue of the roots, indicated that the beads passed through the intercellular space via the apoplastic transport system. Once inside the central cylinder, the 0.2 mum PS beads were transferred from the roots to the stems and leaves via the vascular system following the transpiration stream. We also observed that the PS beads adhered to one another and self-assembled systematically into grape-like and (chain) string-like clusters in the intercellular space of the root and stem vascular tissue of lettuce plant. In contrast to the root and stem, PS beads were dispersed in the leaf tissue. Here, for the first time we provide evidence of the adherence, uptake, accumulation, and translocation of submicrometer MPs within an edible plant. Our findings highlight the previously underappreciated human exposure pathway to MPs through the consumption of contaminated crops and emphasize the need for new management strategies to control the release of MPs waste products into the terrestrial environment. Ultimately, the potential impacts of low range sized MPs on food safety of crop plants and human health need to be urgently considered.  
The Mirror Control System of Parabolic Trough Solar Thermal Based on DCS 会议论文  OAI收割
2nd International Conference on Intelligent Materials and Mechatronics and 2nd International Conference on Solar Energy Materials and Energy, Hong Kong, October 29-30, 2015
作者:  
Wang CX(王晨曦);  Liu MZ(刘明哲);  Xu AD(徐皑冬);  Jin N(金妮)
收藏  |  浏览/下载:25/0  |  提交时间:2016/09/13
Implementation of a fast simulation algorithm for terrain based on dynamic LOD (EI CONFERENCE) 会议论文  OAI收割
IEEE 2011 10th International Conference on Electronic Measurement and Instruments, ICEMI 2011, August 16, 2011 - August 18, 2011, Chengdu, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
In-depth study and explore dynamic quad tree rendering of large-scale terrain. Investigated the problems  which was urgently to be solved  about quad tree. Studied the features and application of dynamic quad tree algorithm and static quad tree algorithm. Analyze and explore the problems about quad tree construction  data storage that is significant in modeling  removing of the grid back  and elimination of T-type fracture. In this study  an algorithm based on storage array was proposed on the basis of the previous research to eliminate T-type fracture. The results showed that the new algorithm not only enhance the streamline effect  but also increased the rendering speed in the large-scale virtual terrain rendering process. The draw rate was enhanced from 8-10 frames/s up to 20-23 frames/s. 2011 IEEE.  
Research of automatic test technology of parameters used in a dual-CCD TV measure-system (EI CONFERENCE) 会议论文  OAI收割
2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China
作者:  
Wang L.;  Li Y.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25
This paper describes a kind of automatic test technology of the parameters used in a dual-CCD TV measure-system (TV -MS) .The TV -MS is the ground control equipment of the anti-tank missile and integrates the technologies of optical  machine and electronics. It is important and key component. The main technical parameters of the TV -MS are field of view  zero point  precision  sensitivity  anti-jamming ability  zooming time and focus time  etc. To insure the TV -MS satisfying the tactical and technical requirements and discover fault and reason  a fast and accurate equipment satisfying the test technical parameters of the TV -MS is urgently needed in manufacture and service. Firstly  the parameter test system converted optical signal to electronic signal  implemented automatic control of the invariant illumination of parallel pipeline output. Secondly  data and command delivering  displaying or printing are realized by using 80C196KB. The experiment result shows that the approach of automatic testing of the Parameters used in a dual-CCD TV -MS is successful and it can be used for all tests of the functions and parameters of the TV -MS. The main innovations are to realize the fast  veracious measure of technical parameters of the dual-CCD TV-MS  and integrate the technologies of optics  machineries and electronics. An advanced means is provided to judge the technical states  find malfunctions and discover the reasons in producing and maintaining process. The equipment suited for anti-tank missile systems is given.