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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:150/0  |  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.  
Efficient electrochemical reduction of bromate by a Pd/rGO/CFP electrode with low applied potentials 期刊论文  OAI收割
APPLIED CATALYSIS B-ENVIRONMENTAL, 2014, 卷号: 160, 期号: 1, 页码: 179-187
Mao, Ran; Zhao, Xu; Lan, Huachun; Liu, Huijuan; Qu, Jiuhui
收藏  |  浏览/下载:32/0  |  提交时间:2015/03/26
Rapid Micro-Patterning of a Conductive PANI/MWNTs-Polymer Composite Using an Optically-induced Electrokinetics Chip 会议论文  OAI收割
IEEE Nanotechnology Materials and Devices Conference (IEEE NMDC), Honolulu, HI, OCT 16-19, 2012
作者:  
Liu N(刘娜);  Liang WF(梁文峰);  Mai, John D.;  Dong ZL(董再励);  Li WJ(李文荣)
收藏  |  浏览/下载:38/0  |  提交时间:2013/12/26
A flexible, dynamically programmable and low-cost method applicable to micro-patterning of a conductive polymer/carbon nanotube composite solution is significant due to the potential applications in many areas. This paper demonstrates a new micro-patterning method for fabricating electrodes from a conductive polyaniline (PANI)/MWNT composite using an optically-induced electrokinetics (OEK) chip. This method quickly patterns flexible polymeric electrodes with different geometries when a square waveform signal with amplitudes from 16-20 Volts and frequencies from 20-30 kHz are applied. The geometric dimensions of the electrodes can be varied dynamically by controlling the size and exposure time of the light pattern. The surface morphology of electrodes patterned by this method is scanned by an atomic force microscope (AFM) and a scanning electron microscope (SEM) which show that the electrodes are uniform and continuous. Furthermore, the geometric dimensions and resistances of the electrodes are measured and analyzed. Experimental results reveal that the relationship between the resistance and geometries of the electrodes obey Ohm's law and the resistivity of the electrodes is about 0.03 Omega.m.  
Layered graphene on surface of carbon fiber (EI CONFERENCE) 会议论文  OAI收割
8th International Vacuum Electron Sources Conference, IVESC 2010 and NANOcarbon 2010, October 14, 2010 - October 16, 2010, Nanjing, China
作者:  
Wang W.;  Wang W.
收藏  |  浏览/下载:44/0  |  提交时间:2013/03/25
Carbon nanomaterials have attracted considerable attention and interest owing to the unique physical and chemical properties. Such as nanodiamonds  carbon nanofibers  carbon nanotubes (CNTs)  graphene and so on  they all have potential applications as field electron emission materials  electrode materials  storage hydrogen materials and composite materials. In this paper we reported the growth of layered graphene(LG) on carbon fibers surface. The LG synthesized on carbon fibers may have potential applications in many fields. For example  using to improve the electric conductivity and chemical stability of carbon fibers substrate  the grown LG can be applied as high performance capacitor  battery  field emission electron source  hydrogen storage owing to large ratio surface and hybrid multiscale composite. 2010 IEEE.  
On orbit MTF measurement of remote sensing camera based on wavelet transform (EI CONFERENCE) 会议论文  OAI收割
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Wang X.;  Wang X.;  Wang X.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
Influence of applied potential on cavitation erosion behavior of type 316L stainless steel in sulfuric acid solution 期刊论文  OAI收割
Corrosion, 2006, 卷号: 62, 期号: 2, 页码: 99-108
S. L. Jiang; Y. G. Zheng; S. Z. Luo; Z. M. Yao
收藏  |  浏览/下载:30/0  |  提交时间:2012/04/13
Fabrication and electron emission of carbon microtubes (EI CONFERENCE) 会议论文  OAI收割
Technical Digest of the 18th International Vacuum Nanoelectronics Conference, IVNC 2005, July 10, 2005 - July 14, 2005, Oxford, United kingdom
作者:  
Liu L.;  Liu L.;  Wang W.;  Wang W.
收藏  |  浏览/下载:46/0  |  提交时间:2013/03/25
Carbon nanotubes have been attracting attention because of their unique physical properties and their application potential for field emission cathode. Carbon nanotubes possess the following properties favorable for field emission material  such as a high aspect ratio and sharp tip  high chemical stability  high mechanical strength  stable at high temperature. Some research works on carbon nanotubes field emitter and field emission display have been reported. Here  a kind of carbon microtubes and its field emission properties are introduced. They have some different properties with carbon nanotubes  and the density is lower than carbon nanotubes bundles. These carbon microtubes are directly synthesized by liquidoid epitaxy method on silicon substrates at low temperature. The field emission properties of carbon microtubes are reported too. Carbon microtubes film is synthesized in liquid by electrolysis. The graphite plate is as anode  and n-silicon substrate with resistivity of 4-8 cm is as cathode. The electrolysis current is about 5-8mA/cm2  and applied voltage is 800-1500V. Temperatures of the methanol base solution is maintained at 60C in process of deposition of carbon microtubes. Carbon microtubes film is observed by scanning electron microscopy(SEM)  as shown in fig.1(a  b). The wall's thickness of carbon microtube is about 60nm. The diameter of carbon microtube is about 0.8 m. Raman spectrum of carbon microtubes film shows the two peaks at 1342and 1560cm-1. The field emission properties of carbon microtubes are measured in high vacuum chamber(10-5Pa). The emission area of carbon microtubes is 0.5cm 0.5cm. The threshold of field emission of the carbon microtubes film is about 3.6V/ m. Field emission property of carbon microtubes film is shown in fig.2. Another  when the electric field between anode and cathode is 10V/ m  the electric field distribution on single carbon microtube is also given after calculation according to electric field theory. Fig 3 shows that electric field distribution vertical section on the of single carbon microtube top with 2 m of highness. These results may help us to understand field emission properties of carbon microtubes. According to research results  it is found that liquidoid synthesis is simple method to produce carbon microtubes cold cathode material  and the carbon microtubes have better field emission properties. 2005 IEEE.  
Phase characteristics of laser beam in fibers (EI CONFERENCE) 会议论文  OAI收割
5th International Workshop on Adaptive Optics for Industry and Medicine, August 29, 2005 - September 1, 2005, Beijing, China
作者:  
Wang L.;  Wang L.;  Liu J.;  Liu J.;  Liu J.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
The phase changing rates1 of laser beam in single mode polarization maintaining fiber (PMF)  Yb-doped rectangular inner cladding dual-clad fiber (DCF) and Yb-doped large-mode-area dual-clad fiber (LMF) are investigated by means of interference under situations with different exterior disturbance  for situations that all the fibers are used as transmission medium only  as well as amplifying medium with the last two. In this paper  phase fluctuation characteristics of the beam transmitted through the fibers with no amplification are presented. The results show that the phase fluctuation frequencies of the laser beam transmitted through these three kinds of fibers are mainly in the range of 100-200Hz  100-300Hz and 80-400Hz respectively in normal laboratory environment. The phase fluctuation frequencies of the laser beam transmitted through the DCF  in cases of when the environment temperature is changing  a constant pressure is applied to the fiber and when vibration is applied  are mainly in the range of 100-600Hz  100Hz-300Hz and 100-500Hz respectively. In the same cases  for the LMF  the phase fluctuation frequencies are mainly in the range of 150-600Hz  100-400Hz and 100-1000Hz  respectively. It indicates that for realizing phase stabilization  the bandwidth of any potential phase control2 system has to be in the range of a few kilohertz.  
THE INFLUENCE OF APPLIED POTENTIAL ON THE EROSION-CORROSION BEHAVIOR OF AISI321 STAINLESS-STEEL IN ACIDIC SLURRY MEDIUM 期刊论文  OAI收割
WEAR, 1995, 卷号: 186, 期号: 2, 页码: 568-572
作者:  
YAO, ZM;  ZHENG, YG;  KE, W
  |  收藏  |  浏览/下载:14/0  |  提交时间:2021/02/02