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浏览/检索结果: 共5条，第1-5条 帮助 限定条件 发表日期：2019     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Robust roll angular error measurement system for precision machines 期刊论文 OPTICS EXPRESS, 2019, 卷号: 27, 页码: 8027-8036 作者:  Cai, Yindi;  Yang, Binhe;  Fan, Kuang-Chao 收藏  |  浏览/下载：3/0  |  提交时间：2019/12/02 Optical constants, Beam diameters  Intensity variations  Laboratory environment  Measurement accuracy  Measurement range  Measurement system  Position detector  Precision machines, Optics   Characteristics of acoustic response from simulated impulsive lightning current discharge 期刊论文 HIGH VOLTAGE, 2019, 卷号: 4, 期号: 3 作者:  Wang, Jianguo;  Cao, Jinxin;  Cai, Li;  Fan, Yadong;  Zhou, Mi 收藏  |  浏览/下载：25/0  |  提交时间：2019/12/05 thunderstorms  lightning protection  lightning  acoustic response  simulated impulsive lightning current discharge  laboratory simulated lightning discharge  acoustic observation experiment  impulsive current generation system  response sound pressure  simulated lightning current  acoustic amplitude  discharging amplitudes  observing distance  response acoustic characteristics  subsequent current peaks  electrical pulses  acoustic pulses  lightning current  natural thunderstorm environment  time 8  0 mus  time 20  0 mus   Establishing and validating of an laboratory information system-based auto-verification system for biochemical test results in cancer patients 期刊论文 2019, 卷号: 33, 期号: 5, 页码: e22877 作者:  Yan, Cuie;  Zhang, Yujuan;  Li, Jia;  Gao, Jia;  Cui, Chanjuan 收藏  |  浏览/下载：7/0  |  提交时间：2020/01/03 auto-verification  biochemical test  cancer  historical extremum  laboratory information system   Quality Assurance of a Hybrid Online Course through Iterative Process Control 会议论文 Proceedings of 2018 IEEE International Conference on Teaching, Assessment, and Learning for Engineering, TALE 2018, 2018-12-04 作者:  Wan, H.;  Liu, K.;  Yu, Y.;  Wang, B.;  Gao, X. 收藏  |  浏览/下载：6/0  |  提交时间：2019/12/30 Efficiency  Iterative methods  Process control  Quality assurance  Students  Teaching  Iterative process  Laboratory system  Process iteration  Progress control  Quality of teaching  Quantitative data  Teaching assistants  Teaching resources  E-learning   食用蔬菜能吸收和积累微塑料 期刊论文 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：63/0  |  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.