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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.

MEAN PROLOCULUS SIZE AS A SALINITY INDEX IN BENTHIC FORAMINIFERA AMMONIA AOMORIENSIS: BASED ON CULTURE AND SEASONAL STUDIES 期刊论文 OAI收割
JOURNAL OF THE PALAEONTOLOGICAL SOCIETY OF INDIA, 2016, 卷号: 61, 期号: 2, 页码: 215-223
作者: Yu, Zhoufei; Lei, Yanli; Li, Tiegang

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Ammonia aomoriensis mean proloculus size salinity culture experiment field study

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.

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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.

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.

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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.

Experiment analysis of CO2 laser disturbance on long-wave infrared HgCdTe detector (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
作者: Wang S.-W.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

Theoretical analysis and experimental study were carried out on the high-power CO2 laser disturbance to long-wave infrared (LWIR) HgCdTe detector in this paper. Based on the practical parameters of experiment the theoretical model of temperature-rise is adopted to calculate the variation of the temperature with the time and the power of laser for laser irradiation on the detector. After that the damage threshold is 110W/cm2. This experimental phenomenon well agrees with the results predicted by the theoretical calculation. The conclusions have a certain reference value for the laser defense of detector. 2011 IEEE. the high-power laser damage mechanism to LWIR detector is discussed and compares with the experimental results of laser irradiation the detector on the distance of 15km. The theoretical and experimental results demonstrate that the interference threshold of the detector is 20.5W/cm 2

Experiment of coherent scatter imaging based digital radiography device (EI CONFERENCE) 会议论文 OAI收割
2011 IEEE International Conference on Computer Science and Automation Engineering, CSAE 2011, June 10, 2011 - June 12, 2011, Shanghai, China
作者: Li B.; Wang K.; Liu J.; Liu J.; Liu J.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

This paper introduces a new imaging method for X-ray coherent scatter based on a new medical digital radiography device. An experimental equipment was set up and the scatter images obtained with it. The scatter images are made of some circles with the same center. With image processing the energy distribution curve extracted from coherent scatter images. The experiment results show that this method is reasonable and feasible. The study will have wide foreground of application. 2011 IEEE.

1D-KBA microscope using double-periodic multilayer (EI CONFERENCE) 会议论文 OAI收割
Advances in X-Ray/EUV Optics and Components IV, August 3, 2009 - August 5, 2009, San Diego, CA, United states
作者: Wang Z.; Wang X.; Wang X.; Wang X.; Wang Z.

收藏 | 浏览/下载：12/0 | 提交时间：2013/03/25

To study the action of shock wave in CH target one-dimensional grazing incidence KBA microscope for 4.75keV energy was set up. Because of strong absorption in air 4.75keV energy microscope can just work in vacuum. Accordingly the alignment and assemblage will be very complicated and difficult. A special multilayer method using double periodic multilayer was proposed to solve this problem. This multilayer has high reflectivity not only for 4.75keV X-rays but also for 8keV X-rays at the same grazing incidence angle. It means 1D-KBA microscope has the same light trace for different working energies. Therefore we can implement the alignment and assembly of 4.75keV system by the help of 8keV X-rays. Because 8keV X-rays is very easy produced by X-ray tube and has strong transmittability in air the alignment and assemblage process became relatively easy. By now we have finished the alignment experiment at 8keV and obtained imaging results. The performance is about 2-3m resolution in 250m field of view. It is coincide with the calculation. 2009 SPIE.

Analysis of laser jamming to satellite-based detector (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China
作者: Guo L.-H.; Guo R.-H.; Wang S.-W.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

The reconnaissance satellite communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain so laser disturbing satellite detector is possible. In order to determine its feasibility the theoretical analyses and experimental study are carried out in the paper. Firstly the influence factors of laser disturbing satellite detector are analyzed in detail which including laser power density on the surface of the detector after long distance transmission and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit but dependence on the following parameters: laser average power in the ground laser beam quality tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally using the theoretical model the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2 which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser even decrease laser average power it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.

Electrophoresis deposition of carbon nanotubes for triode type CNT-FED cathode (EI CONFERENCE) 会议论文 OAI收割
Asia Display 2007, AD'07, March 12, 2007 - March 16, 2007, Shanghai, China
作者: Song H.; Jiang H.; Li Z.; Li Z.

收藏 | 浏览/下载：253/0 | 提交时间：2013/03/25

This study explores an electrophoretic process to selectively assemble carbon nanotube emitters into normal triode structure for triode type carbon nanotube field emission display cathode. In this process the carbon nanotubes are migrated and deposited into triode structure by an applied voltage between the gate electrode and cathode electrod. The applied voltage is also used to keep the carbon nanotubes off adsorption on the gate electrode. The experiment results show that the carbon nanotubes are selectively defined inside of gate holes and each hole has the same packing density. The process which is low cost and easily scaling up is an alternative method to prepare triode type carbon nanotube field emission display cathode.

Low threshold field electron emission of diamond films (EI CONFERENCE) 会议论文 OAI收割
ICO20: Display Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
作者: Liu L.; Wang W.; Wang W.; Li M.; Liu L.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

Since CVD diamond film possesses desirable properties it has been widely investigated and much research has been made in this field. In this experiment we mainly studied the characteristics of field emission from the CVD diamond films. The motivation for the experiment is to gain some insight into a possible emission mechanism. The diamond films are grown using a hot filament chemical vapor deposition basing on the diamond micro-grits on silicon substrates. And the diamond micro-grits are deposited on silicon substrates using electrophoresis coat method through a solution of diamond micro-grits in ethyl alcohol. This study has revealed that emission can be obtained at fields as low as 1.8V/m. And the field emission measurements were carried out at a pressure of 10-4Pa.