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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：146/0  |  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.  
Structural design and simulation analysis of ejector used in automotive power steering oil discharge equipment (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Mechanical Engineering, Materials Science and Civil Engineering, ICMEMSCE 2012, August 18, 2012 - August 20, 2012, Harbin, China
Cheng K.; Zou H.; Kong X.; Tang J.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
The approximate calculation of atmospheric path radiance in close range and horizontal direction (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Sensors, Measurement and Intelligent Materials, ICSMIM 2012, December 26, 2012 - December 27, 2012, Guilin, China
作者:  Sun Z.;  Chen Y.;  Zhang Y.
收藏  |  浏览/下载：31/0  |  提交时间：2013/03/25
Atmospheric path radiance is the key factor in the accuracy of objective radiation measurement. In the traditional radiation character measurements  it is compared with the results of MODTRAN and measurement in experiment. It is revealed that the accuracy of software is 7.8%  under the help of the atmospheric observation equipment  and the formula is 4.9%  MODTRAN and other software likewise  which could demonstrate the validity of the pproximate calculation formula in close range and horizontal direction. In this article  the indeterminacy rate could be around 10~20%  in the process of deducing and experiment  it is highly restricts the measurement accuracy of objective radiation. For this reason  the validity of the approximate calculation formula in close range and horizontal direction is fully proved  it is quite significant to develop the study of measure and calculation in path radiance. The approximate calculation formula for path radiance in close range and horizontal direction is expressed in this article  which supply a new method in approximate calculation of path radiance for objective radiation measurement. (2013) Trans Tech Publications  Switzerland.  
Image mosaic technique based on the information of edge (EI CONFERENCE) 会议论文  OAI收割
2012 3rd International Conference on Digital Manufacturing and Automation, ICDMA 2012, July 31, 2012 - August 2, 2012, Guilin, Guangxi, China
作者:  Wang Y.-Q.
收藏  |  浏览/下载：35/0  |  提交时间：2013/03/25
Image mosaic is an important branch in the field of image processing. This paper designs and realizes an image mosaic technique based on the information of edge. The technology is suitable for engineering application. First of all  two images of the adjoining frames are processed by convolution operation  get the edge images. And then we cut edge image into pieces and compute their spatial frequency. According to the value of the spatial frequency select reasonable registration model group. We compute correlation strength and the value of movement offset which are the model group and the current frame edge image. We can complete image mosaic by them. We use video sequence which of the resolution is 1024 * 768 do the experiment. The results show that the method has good effect and strong adaptability. Algorithm is high efficiency which running time is 24 ms. It is suitable for real-time processing requirements of the application. This method is an effective mosaic technique which is suitable for engineering application. 2012 IEEE.  
A signal process system for photoelectric encoder based on C8051F021 MCU (EI CONFERENCE) 会议论文  OAI收割
2nd World Congress on Computer Science and Information Engineering, CSIE 2011, June 17, 2011 - June 19, 2011, Changchun, China
作者:  Gao X.
收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25
Field-line coupling interference prediction of LCD module in high-power TEA CO2 laser system (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
Ge X.; Li X.
收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25
High-resolution Fourier lens design (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
Gu S.; Liu C.; Jin G.
收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25
Research on moving target tracking scene simulation technology under battlefield complicated environment based on Vega (EI CONFERENCE) 会议论文  OAI收割
4th International Congress on Image and Signal Processing, CISP 2011, October 15, 2011 - October 17, 2011, Shanghai, China
Wang S.; Wei Y.-J.
收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25
In order to better simulate the real environment of the battlefield  which has moving-target and the complicated background and to simulate the tracking process of the target with 3d's simulation. This paper introduce a development platform of the Vega 3d simulation software  and how to use the Vega to simulate the complex battlefield background  which has the sky  the explosion effects in the ground  the fly parameters of fighter planes. It reappear a complete process  which contains capturing target and tracking target. Experiment indicate that the Vega development platform is convenient and fast  and can achieved the design parameters for the task's demands. It also has many advantages  that contains repeating the performance of real experiment and reducing the expenses of the military experiment. 2011 IEEE.  
The ship-borne infrared searching and tracking system based on the inertial platform (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  Li Y.;  Zhang H.;  Zhang H.;  Li Y.;  Li Y.
收藏  |  浏览/下载：38/0  |  提交时间：2013/03/25
As a result of the radar system got interferenced or in the state of half silent  it can cause the guided precision drop badly In the modern electronic warfare  therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings  but when interference is in the process of radar leading  especially the electro-optical equipment is influenced by the roll  pitch and yaw rotation  it can affect the target appear outside of the field of optoelectronic devices for a long time  so the infrared optoelectronic equipment can not exert the superiority  and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly  the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene  the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking  when the lead deviation of the radar is great. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Design and demonstration of micro multi-step mirrors and light source in micro FTIR (EI CONFERENCE) 会议论文  OAI收割
6th IEEE International Conference on Nano/Micro Engineered and Molecular Systems, NEMS 2011, February 20, 2011 - February 23, 2011, Kaohsiung, Taiwan
Liang Z.; Fu J.; Feng C.; Liang J.
收藏  |  浏览/下载：43/0  |  提交时间：2013/03/25
To obtain high resolution  high signal-to-noise ratio (SNR)  high reliability and real time in wide spectral range  we study the space modulation Micro Fourier Transform Spectrometer (FTS) based on multi-step mirrors covering the spectral range of 3-5m and 8-12 m in theory and experiment. The influences of spectrum reconstruction caused by the diffraction and extended light source in Fourier Transform Infrared Spectrometer (FTIR) are analyzed. A method to reduce the noises in spectrum reconstruction and the relationship between coherent intensity and solid angle of light source are discussed. An extended light source with suitable size is chosen  considering the requirement of SNR and spectrum resolving power in the optical design. Furthermore  the fabrication of micro multi-step mirrors  which is the core part of FTS  is investigated. Three methods for fabricating multi-step micro mirrors are demonstrated. 2011 IEEE.