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浏览/检索结果: 共9条,第1-9条 帮助

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The Real Electrochemical Boundary Conditions Based on the Polarization Process 期刊论文  OAI收割
JOURNAL OF MARINE SCIENCE AND ENGINEERING, 2025, 卷号: 13, 期号: 6, 页码: 16
作者:  
Wang, Zaifeng;  Zhang, Jie;  Liu, Haishan;  Hou, Baorong
  |  收藏  |  浏览/下载:3/0  |  提交时间:2025/08/20
Preserving traditional systems: Identification of agricultural heritage areas based on agro-biodiversity 期刊论文  OAI收割
PLANTS PEOPLE PLANET, 2024
作者:  
Bai, Yunxiao;  Li, Xiaoshuang;  Feng, Yuqing;  Liu, Moucheng;  Chen, Cheng
  |  收藏  |  浏览/下载:94/0  |  提交时间:2024/02/05
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:186/0  |  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.  
Comparison of Spatial Distribution Patterns of Seed Rain between Larch Plantations and Adjacent Secondary Forests in Northeast China 期刊论文  OAI收割
FOREST SCIENCE, 2016, 期号: 6, 页码: 652-662
作者:  
Yan, Qiaoling;  Zhu, Jiaojun;  Gang, Qun;  Huang, Liyan;  Wang, G. Geoff
收藏  |  浏览/下载:43/0  |  提交时间:2017/05/11
Prediction model of sulphur distribution ratio between CaO-FeO-Fe2O3-Al2O3-P2O5 slags and liquid iron over large variation range of oxygen potential during secondary refining process of molten steel based on ion and molecule coexistence theory 期刊论文  OAI收割
IRONMAKING & STEELMAKING, 2016, 卷号: 43, 期号: 1, 页码: 39-55
作者:  
Yang, X. M.;  Li, J. Y.;  Zhang, M.;  Zhang, J.
收藏  |  浏览/下载:44/0  |  提交时间:2016/04/22
Looking below the ground: Prediction of Tuber indicum habitat using the Weights of Evidence method 期刊论文  OAI收割
ECOLOGICAL MODELLING, 2012, 卷号: 247, 页码: 27-39
作者:  
Yang, Xue-Qing;  Kodikara, Gayantha R. L.;  Luedeling, Eike;  Yang, Xue-Fei;  He, Jun
收藏  |  浏览/下载:129/0  |  提交时间:2015/06/17
Inhibition of electromagnetic interference in control system based on DSP of high-power TEA CO2 laser (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
作者:  
Meng F.-J.;  Guo L.-H.;  Wang H.-Q.
收藏  |  浏览/下载:69/0  |  提交时间:2013/03/25
The strong electromagnetic interference (EMI) generated in high-power TEA C02 laser system mainly comes from main discharge circuit  pulse spark switch and power supply. Such strong EMI causes great damage and interference to the control system based on DSP. In this paper  we present the interference sources and their distribution and propose the methods of anti-interference. Measures for hardware design include weakening transient ground potential difference by using equipotential lines between devices  using signal isolation interface to inhibit the transient ground potential interference  and rational layout  shielding and filtering to the control system. And methods for software design include range-limited filter  self-diagnosis and self-repair for the critical data and anti-interference during abnormal reset. The EMI has been inhibited effectively by the anti-interference method proposed above. The result shows that: the software anti-interference method is as important as the hardware anti-interference method for the control system in a complex environment of strong EMI. 2010 IEEE.  
The synthesis and field emission property of carbon nanotubes on carbon fibers substrate (EI CONFERENCE) 会议论文  OAI收割
Technical Digest of the 20th International Vacuum Nanoelectronics Conference, IVNC 07, July 8, 2008 - July 12, 2008, Chicago, IL, United states
Leyong Z.; Weibiao W.; Jingqiu L.; Yuxue X.; Da L.; Song C.; Haifeng Z.
收藏  |  浏览/下载:48/0  |  提交时间:2013/03/25
Using ferrocene as catalyst precursor  C2H2 as carbon source  carbon nanotubes (CNTs) with uniform density were synthesized on carbon fibers substrate by floating catalyst method. The morphology and microstructure were characterized by field emission scanning electron microscope (FESEM) and high-resolution transmission electron microscopy (HRTEM). The observation showed that the length of CNTs is about 2 m  the average space between adjacent CNTs is about 300 nm and the diameter of CNT is about 45 nm. The less dense "short and stubby" aligned CNTs films should have good electron field emission characteristics. The results of field emission showed that the emission current of CNTs/carbon fibers was 5 A at the field of 2.5 V/m  and the emission current can be 280 A with a field of 7 V/m (the specimen area is 0.25 cm2 and the distance between cathode and anode is 200 m). The calculation based on the F-N plot indicated that the field enhancement factor of CNTs tip is 499122. Using the conductivity and chemical stability of carbon fibers and the uniform and sparse density distribution of CNTs on carbon fibers substrate  the tip predominance of carbon nanotubes can be exerted  and simultaneously the effect of screening effects between adjacent carbon nanotubes on the field emission performance can also be effectively decreased. The CNTs synthesized on carbon fibers substrate has many predominances for the fabrication of cold cathode devices. For example  using the removability of carbon fibers  the cathode of CNTs/carbon fibers can be arbitrarily moved  enlaced or combined to form different patterns  and the cathode of CNTs/carbon fibers can be also fabricated in large size. Therefore  CNTs/carbon fibers may have potential application in field emission displays.  
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:69/0  |  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.