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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

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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.

Research and optimization on media access control delay of CAN (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Information Technology and Management Innovation, ICITMI 2012, November 10, 2012 - November 11, 2012, Guangzhou, China
作者: Zhang H.; Zhang W.; Zhang W.; Zhang H.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

With data quantity increasing dramatically and signal transmission period becoming more and more fast the media access control delay has proved to be one of the main influence factors of CAN network real-time. Firstly an equivalent numerical simulation model of CAN bus network is built to derivate the mathematical expression of media access control delay. Secondly optimization measures are further proposed to improve the data communication real-time. At last the optimization measures tested by experiments are proved to be correct and effective. (2013) Trans Tech Publications Switzerland.

Retrieval of snow depth in Northeast China using FY-3B/MWRI passive microwave remote sensing data (EI CONFERENCE) 会议论文 OAI收割
Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states
Ren R.; Gu L.; Chen H.; Cao J.

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Comparing with optical remote sensing techniques passive remote sensing data have been proved to be effective for observing snowpack parameters such as snow depth and snow water equivalent which can penetrate snowpack without clouds interferences. The Microwave Radiation Imager (MWRI) loaded on the Chinese FengYun-3B (FY-3B) satellite is gradually used in the global environment research through November 2011. In this paper we proposed a snow depth retrieval algorithm to estimate snow depth in Northeast China using MWRI passive microwave remote sensing data. A decision tree method of snow identification was firstly designed to distinguish different snow cover conditions in order to eliminate other interference signals. After using the proposed decision tree method the processing results were further used to retrieve the snow depth in Northeast China. Finally the practical snow depth data and the MODIS data were collected for the accuracy assessment of the proposed snow depth retrieval method. The experimental results demonstrated that the RMSE of snow depth used the proposed method was approximately 3 cm in Northeast China. 2012 SPIE.

Improved modulation method for optical module based on compensation technology (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Industrial Control and Electronics Engineering, ICICEE 2012, August 23, 2012 - August 25, 2012, Xi'an, China
Cheng P.; Yu W.-J.; Wang R.-G.; Zheng X.-F.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

In order to increase the performance of the optical module an improved modulation method based on compensation technology is provided. Firstly the development of the optical module is illustrated. Secondly the combination and the main parameters of the optical module are listed. Thirdly in according to the existing module package the method based on compensation technology is elaborated. Finally this method is used in one of internet device and the experimental results show that this method is able to ensure the superior performance of the module. 2012 IEEE.

Method for improving transmission efficiency in 40Gbit/s system based on dispersion compensation (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Industrial Control and Electronics Engineering, ICICEE 2012, August 23, 2012 - August 25, 2012, Xi'an, China
Yu W.-J.; Wang R.-G.; Cheng P.; Zheng X.-F.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

In an effort to overcome the problem that the transmission efficiency is too low in 40Gbit/s system a method based on dispersion compensation is provided. Firstly the application background of 40Gbit/s system the key using technologies and the shortcomings and advantages of 40Gbit/s system are possessed. Secondly an application program of 40Gbit/s system based on dispersion compensation is given. At the same time this program is analyzed. Thirdly this program is compared with another program which has been widely used in 40Gbit/s system. Finally the compared results show that this program is able to improve the transmission efficiency apparently. 2012 IEEE.

Improved method of target detection on optoelectronic hybrid joint transform correlator in cluttered scences (EI CONFERENCE) 会议论文 OAI收割
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
作者: Yang L.; Yang L.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

A classical joint transform correlator (JTC) usually yields large correlation sidelobes as well as a large correlation peak width strong zero-order peak and low diffraction efficiency which make the detection ability of JTC lower. To overcome these difficulties firstly a joint power spectrum (JPS) subtraction technique in Fourier plane was proposed where reference image power spectrum and object image power spectrum are subtracted from the JPS before inverse Fourier-transform operation it is obvious that the modified JPS removes the zero-order term. Secondly a fringe-adjusted filter (FAF) was presented to suppress sidelobes and noises. The modified JPS is multiplied by a FAF before the inverse Fourier-transform operation to obtain the cross-correlation peak. Computer simulations demonstrated the improved method can obviously remove zero-order diffraction and effectively suppress the sidelobes and noises compared with classic JTC and then improve the detection ability for JTC. Experimental results presented the sharp correlation peak and also confirmed the method effectiveness. (2012) Trans Tech Publications Switzerland.

Research on soybean security of China based on system dynamics (EI CONFERENCE) 会议论文 OAI收割
31st Chinese Control Conference, CCC 2012, July 25, 2012 - July 27, 2012, Hefei, China
作者: Gao M.-H.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

Based on considerations of soybean production imports and exports trade processing and consumption we study the soybean industry of China with the method of system dynamics. Firstly we build the SD model of soybean industry. Secondly we optimize soybean security policy simulation dynamic model and simulate the model based on our country specific situation. At last on the basis of the simulation results we analyze current domestic soybean industry security situation and provide a method to make suggestions for soybean security policy. 2012 Chinese Assoc of Automati.

The application of Kalman filtering technique on the multi-position strap-down north seeking system (EI CONFERENCE) 会议论文 OAI收割
2012 5th International Symposium on Computational Intelligence and Design, ISCID 2012, October 28, 2012 - October 29, 2012, Hangzhou, China
作者: Liu S.-J.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

In order to fit the sin wave curve of a multiposition strap-down north seeking system and to calculate the real north angle accurately the data collected from the Dynamically tuned gyro(DTG) must be filtered firstly to reduce the noise jamming. The principles of the system are introduced. The factors influencing the measuring precision are also analyzed. Then The DTG data are processed by second-order Butterworth filtering and Kalman filtering together. Experimental results indicate that the built-up filtering method can reduce noise jamming more effectively than second-order Butterworth filtering in the low frequency. 2012 IEEE.

Alternating stress dynamics analysis of harmonic gear flexible wheel (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Electrical Insulating Materials and Electrical Engineering, EIMEE 2012, May 25, 2012 - May 27, 2012, Shenyang, Liaoning, China
作者: Li M.

收藏 | 浏览/下载：38/0 | 提交时间：2013/03/25

This article is the study of alternating stress of flexible wheel in harmonic gear drive system. Firstly then Finally according to elasticity theory to theoretically analyze flexible wheel stress based on the basic principle of sub-structure modal synthesis method based on the dynamics simulation use the software of UG to analyze the alternating stress simulation results of flexible wheel and compare theoretical results and simulation results to come conclusion. The results show that: altering stress simulation results of flexible wheel are coincident with theoretical simulation results PATRAN and ADAMS to carry out co-simulation have a deeper understand the stress change trend in the drive process of flexible wheel lay a foundation for further carrying out dynamics simulation of harmonic gear drive system. (2012) Trans Tech Publications Switzerland.

Design of high speed and parallel compression system used in the big area CCD of high frame frequency (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Precision Engineering and Non-Traditional Machining, PENTM 2011, December 9, 2011 - December 11, 2011, Xi'an, China
作者: Li G.-N.; Jin L.-X.; Zhang R.-F.; Wang W.-H.; Li G.-N.

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According to the area CCD camera of characteristics such as high resolution capacity and high frame frequency this paper puts forward a high speed and parallel image compression system of high integration degree. Firstly according to the work principle of the area CCD FPGA is adopted to realize the timing driving and multichannel and parallel analog signal handling to raise the export frame frequency of the area CCD. Secondly with an image compression scheme based on FPGA embedded processor MicroBlaze and ADV212 compression chip real time image compression and the high speed area CCD are realized. Finally by detecting the analog signal of the area CCD output the real time compression of the big area CCD image is carried out in different compression ratios and the compression performance is analyzed. Experiment result shows that this scheme can realize real time image compression with the biggest data rate of 520Mbps. When compression bit ratio is 0.15 the signal-to-noise ratio of peak value can reach 36 dB. Image collection and image compression are integrated which reduces the data transmission between them and improves systematic integration degree.