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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：147/0 \| 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.
	Prediction of the anti-glioma therapeutic effects of temozolomide through the in vivo molecular imaging of the MMP expression 期刊论文 OAI收割 Biomedical Optics Express, 2018, 卷号: 9, 期号: 7, 页码: 3193-3207 作者: Li Li; Du Yang; Xiang Dehui; Chen Liang; Shi Zhifeng \| 收藏 \| 浏览/下载：45/0 \| 提交时间：2019/02/18 Mdical And Biological Imaging, Tomographic Imaging, Spectroscopy, Fluorescence And Luminescence, Optical Diagnosis For Medicine
	A novel near-infrared nanomaterial with high quantum efficiency and its applications in real time in vivo imaging 期刊论文 OAI收割 NANOTECHNOLOGY, 2018, 卷号: 29, 期号: 20 作者: Cui, X. X.; Fan, Q.; Shi, S. J.; Wen, W. H.; Chen, D. F. \| 收藏 \| 浏览/下载：43/0 \| 提交时间：2018/04/12 Nanomaterials Biomaterials Medical Optics And Biotechnology Fluorescence Microscopy Spectroscopy Fluorescence And Luminescence
	Novel l(2,1)-norm optimization method for fluorescence molecular tomography reconstruction 期刊论文 OAI收割 BIOMEDICAL OPTICS EXPRESS, 2016, 卷号: 7, 期号: 6, 页码: 2342-2359 作者: Jiang, Shixin; Liu, Jie; An, Yu; Zhang, Guanglei; Ye, Jinzuo \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2016/10/20 Image Reconstruction Techniques Spectroscopy Fluorescence And Luminescence Tomography
	Optical characterization of bare CdSe and CdSe/CdS core/shell nanocrystals (EI CONFERENCE) 会议论文 OAI收割 ICO20: Biomedical Optics, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu L.; Yu B.; Liu L. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Thiol-capped CdSe/CdS core/shell nanocrystals (NCs) which show high luminescence quantum yield are synthesized in an aqueous solution. UV-Vis absorption spectroscopy and photoluminescence (PL) spectroscopy are employed to analyze optical characters and stabilities of NCs. Furthermore PL properties are studied in a temperature range between 77K and 300K. The PL peak position of bare CdSe NCs shifts toward shorter wavelengths and the band becomes sharper with decreasing temperature. On the same condition the PL peak position of CdSe/CdS core/shell NCs keeps unconverted nearly with the variation of temperature. Photostability of bare CdSe NCs and CdSe/CdS core/shell NCs are compared under the 325nm laser irradiation. It takes 78 seconds that the PL intensity declines to the half for CdSe NCs but 442 seconds for CdSe/CdS core/shell NCs. The fluorescence decay lifetime increases about six times after overcoating. The results indicate that the CdS shell can improve the low temperature PL stability and photostability of CdSe NCs effectively.
	TeO2-ZnO-Na2O-K2O玻璃中Er^3＋离子掺杂浓度对其发光及荧光寿命的影响期刊论文 OAI收割物理学报, 2005, 卷号: 54, 期号: 7, 页码: 3418, 3423 陈炳炎; 刘粤惠; 陈东丹; 姜中宏收藏 \| 浏览/下载：1253/308 \| 提交时间：2009/09/24 Er^3+离子 TeO2-ZnO-Na2O-K2O glasses 掺杂浓度 Er3+ ions 荧光寿命 concentration doped 碲酸盐玻璃 luminescence and fluorescence lifetime 吸收光谱发射光谱发射截面发光强度荧光强度猝灭效应强度降低实验确定浓度猝灭最优值
	The effects of oxygen partial pressure on the optical absorption edge and the UV emission energy of ZnO films 期刊论文 OAI收割 chin. opt. lett., 2005, 卷号: 3, 期号: 7, 页码: 428, 431 Ruijin Hong; Jianda Shao; Hongbo He; 范正修收藏 \| 浏览/下载：1105/120 \| 提交时间：2009/09/22 thin films 300.6470 spectroscopy semiconductors 310.6860 thin films optical properties 170.6280 spectroscopy fluorescence and luminescence