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Modified optical remote sensing algorithms for the Pearl River Estuary

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Frontiers of Earth Science 2015年第4期9卷 732-741页

作者： Man-Chung CHIM Jiayi pan Wenfeng lai Institute of Space and Earth Information Science The Chinese University of Hong Kong Hong Kong SAR China

This study aims to develop new algorithms to retrieve sea surface parameters including concentrations of Chlorophyll a （Chl a） and Suspended Particulate Matter （SPM）, and absorbance of Colored Dissolved Organic Matter （aCDOM） by incorporating the contribution of red bands to make them more adaptable to case 2 waters. Optical remote sensing algorithms have demonstrated efficient retrieval of Chl a, SPM, and aCDOM, yet they are not very accurate especially for coastal areas. It has also been found that the default algorithm has overestimated Chl a in the Pearl River Estuary, and shown poor correlation for CDOM absorbance. By incorporating the red band ratios into the algorithm, a correction effect has been shown, which improves the accuracy of quantifying the actual concentration. Modeling and data fitting of the algorithm have been done based on 61 data samples collected in the Pearl River estuary during a cruise from 3 to 11 May 2014. The study also attempts to modify the aerosol correction bands used in SeaDAS to prevent saturation of these bands. The modified algorithms showed an R-Square value of 0.7289 for Chl a fitting, and 0.7338 for CDOM fitting, and corrected overestimation of Chl a concentration in the Pearl River estuary.

关键词： optical remote sensing algorithm Pearl River Estuary

Comparative Proteomic Analysis of Wheat (Triticum aestivum L.) Hybrid Necrosis

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Journal of Integrative Agriculture 2013年第3期12卷 387-397页

作者： JIANG Qi-yan HU Zheng pan Xing-lai ZHANG Hui National Key Facilities for Crop Genetic Resources and Improvement Institute of Crop Sciences Chinese Academy of Agricultural Sciences Food Crop Science Department Cotton Research Institute Shanxi Academy of Agriculture Sciences

Hybrid necrosis is the gradual premature death of leaves or plants in certain Fj hybrids of wheat （Triticum aestivum L.）. Comparison of protein expression in necrotic and normal wheat leaves showed that the abundance of 33 proteins was changed significantly, and 24 of these proteins were identified. These proteins were involved in plant growth and development, antioxidation, photosynthesis and carbon assimilation, amino acid and protein biosynthesis, cytological signal transduction, DNA and RNA modification, protein transport, folding and assembly according to their functions. The down-regulation of uroporphyrinogen decarboxylase and the up-regulation of lipoxygenases in necrotic leaves may be related to the oxidative stress in the necrotic cells. The heat shock proteins may play the cytoprotective role. The differential expression of photosynthesis and carbon assimilation related proteins indicated chlorophyll biosynthesis and chloroplast development were inhibited and might finally cause the gradual chlorosis and cell death in necrotic leaves. The results of this study give a comprehensive picture of the post-transcriptional response to necrosis in hybrid wheat leaves and serve as a platform for further characterization of gene function and regulation in wheat hybrid necrosis.

关键词： hybrid necrosis proteomic wheat differentially expressed protein

A secure routing model based on distance vector routing algorithm

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Science China(Information Sciences) 2014年第1期57卷 137-149页

作者： WANG Bin WU ChunMing YANG Qiang lai pan LAN JuLong GUO YunFei College of Computer Science Zhejiang University College of Electrical Engineer Zhejiang University School of Computer Engineering Nanyang Technological University National Digital Switching System Engineering and Technological Research Center

Distance vector routing protocols have been widely adopted as an efcient routing mechanism in current Internet,and many wireless ***,as is well-known,the existing distance vector routing protocols are insecure as it lacks of efective authorization mechanisms and routing updates aggregated from other *** a result,the network routing-based attacks become a critical issue which could lead to a more deteriorate performance than other general network *** efciently address this issue,this paper,through analyzing the routing model and its security aspect,and presents a novel approach on guaranteeing the routing *** on the model,we present the security mechanism including the message exchange and update message security authentication *** suggested approach shows that the security mechanism can efectively verify the integrity and validate the freshness of routing update messages received from neighbor *** comparison with exiting mechanisms(SDV,S-RIP etc),the proposed model provides enhanced security without introducing significant network overheads and complexity.

关键词： routing security distance vector auxiliary trustable model authentication metric

Spectral Characteristics of LiSrBO_3:Tb^(3+) Green Phosphor

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Chemical Research in Chinese Universities 2009年第5期25卷 610-613页

作者： LI pan-lai WANG Zhi-jun YANG Zhi-ping GUO Qing-lin College of Physics Science ＆ Technology Hebei University Baoding 071002 P. R. China

LiSrBO3：Tb^3＋ green phosphor was synthesized by means of a solid state reaction and its spectral characteristics were studied. The emission spectrum of LiSrBO3：Tb^3＋ consists of four major bands at 486, 544, 595 and 620 nm under the excitation of near ultraviolet irradiation, which are originated from the ^5Da→^7F6, ^5D4→^7F5, ^5D4→^7F4 and ^5D4→^7F3 characteristic transitions of Tb^3＋, respectively. Monitored at 544 nm, the excitation spectrum of the phosphor extends from 220 nm to 390 nm, with the excitation peaks centered at 242, 277, 368 and 381 nm, respectively. The effect of Tb^3＋ concentration on the emission intensity of LiSrBO3：Tb^3＋ was also investigated. The results show that firstly the intensity increases with increasing Tb^3＋ concentration, reaches a maximum value at 3%（molar fraction） Tb^3＋ and then decreases, showing a concentration self-quenching, whose mechanism is proposed as a d-d interaction based on Dexter theory. The emission intensity of LiSrBO3：Tb^3＋ was enhanced by co-doping Li^＋, Na^＋ and K^＋.

关键词： LiSrBO3:Tb^3+ Green phosphor Spectral characteristics

Efficient piezo-catalytic dye degradation using piezoelectric 6H-SiC under harsh conditions

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Rare Metals 2024年第7期43卷 3173-3184页

作者： Lin-Lin Zhou Tao Yang Kang Wang lai-pan Zhu En-Hui Wang Kuo-Chih Chou Hai-Long Wang Xin-Mei Hou Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Institute of Steel Sustainable Technology Liaoning Academy of MaterialsShenyang 110000China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Materials Science Engineering Zhengzhou UniversityZhengzhou 450001China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing University of Science and TechnologyBeijing 100083China

The development of novel piezoelectric catalysts against harsh conditions is indeed crucial for improving the piezo-catalytic degradation efficiency of colored organic dyes in *** this work,6H-SiC nanoparticles(NPs)are utilized to piezo-catalytic degrade rhodamine B(RhB)and methylene blue(MB)under ultrasonic vibration for the first *** degradation efficiency of RhB and MB reaches 98.8%and 98.7%within 80 *** piezoelectricity of 6H-SiC is comprehensively analyzed by the piezoresponse force microscope(PFM)and finite element method(FEM).The strong oxidizing active free radicals generated by the continuous piezoelectric polarized electric field of 6H-SiC,i.e.,·O_(2)^(-)and·OH,induce the decomposition reactions of colored organic dyes in *** the dyes are proven to degrade to harmless or less-harmful products gradually during the piezo-catalysis process by high-performance liquid chromatography tandem mass spectrometry(HPLC-MS).Moreover,RhB is also decomposed efficiently by 6HSiC NPs under acidic and alkaline *** results prove the feasibility of 6H-SiC for decomposing common water pollutants under harsh conditions and provide a new perspective for water purification.

关键词： Piezo-catalytic degradation 6H-SiC Rhodamine B(RhB) Methylene blue(MB) Harsh conditions

Au nanocomposite enhanced electret film for triboelectric nanogenerator

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Nano Research 2018年第6期11卷 3096-3105页

作者： Bao Dong Chen Wei Tang Chi Zhang Liang Xu lai pan Zhu Lei Jing Yang Chuan He Jian Chen Long Liu Tao Zhou Zhong Lin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing 100083 China CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology (NCNST) Beijing 100190 China School of Material Science and Engineering Georgia Institute of Technology Atlanta Georgia 30332 USA

A triboelectric nanogenerator （TENG） with an organic nanocomposite electret thin film as the triboelectric layer for mechanical energy harvesting was investigated systematically. In combination with corona charging, a TENG was fabricated by using embedded-nanocapacitor-structure polytetrafluoroethylene （PTFE） impregnated with gold nanoparticles （Au-NPs）. The output performances, stability, and durability of the TENGs with Au-PTFE nanocomposite films were characterized after being washed in water. It was found that the output current increases by 70% and the equivalent surface charge density （ESCD） reaches 85 μC/m^2 in comparison to the virgin PTFE film. Such outstanding performance is likely due to the equivalent nanocapacitors between the Au-NPs and PTFE molecules, which serve as nano charge traps in the nanocomposite electret film under negative high-voltage corona charging. This work not only expands the practical applications of TENGs, but also opens up new possibilities for the development of high performance triboelectric materials.

关键词： equivalent nanocapacitor structure polytetrafluoroethylene(PTFE) electret thin film gold nanoparticles equivalent surface charge density

Luminescence and Site Occupancy of Eu2＋ in Ba2 Ca（BO3）2

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Chinese Physics Letters 2011年第1期28卷 190-192页

作者： LI pan-lai WANG Zhi-Jun YANG Zhi-Ping GUO Qing-Lin Colleg-e of Physics Science and Technology Hebei University Baoding 071002

A green phosphor Ba2Ca（BOa）2：Eu2＋ was syntheMzed by a high temperature solid-state reaction method under a reductive amosphere,, The luminescence and site occupancy of Eu2＋ in Ba2Ca（BOa）2 are investigated. Ba2Ca（BO3）2：Eu2＋ shows one green band （537nzn） under 400nln near ultraviolet excitation which is suitable for UV LED. Ca2＋ and Ba2＋ ions in Ba2Ca（BO3）2 are replaced by Eu2＋ ions, the Ba2Ca（BO3）2：Eu2＋ shows a dissymmetrical emission band. The influence of Eu2＋ doping concentrations on the emission intensity of Ba2Ca（BOa）2：Eu2＋ is studied. It is found that the emission intensity is influenced by the Eu2＋ concentration and reaches the maxinmm value at 2% Eu2＋, According to the Dexter theory, the concentration quenching mechanisms of Eu2＋ in Ba2 Ca（B03）2 are the d - d interaction,

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Synthesis of Red Phosphor CaZrO_(3):Eu^(3+) for White Light-Emitting Diodes

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Chinese Physics Letters 2011年第2期28卷 208-211页

作者： LI Xu GUAN Li AN Jia-Yi JIN Li-Tao YANG Zhi-Ping YANG Yan-Min LI pan-lai FU Guang-Sheng College of Physics Science and Technology Hebei UniversityBaoding 071002 Tangshan Vocational and Technical College Tangshan 063004

A red-emitting CaZrO_(3):Eu^(3+)phosphor has been prepared by solid state reaction and its luminescent properties are *** crystal structure is investigated by the x-ray *** energy transitions of^(5)Do→^(7)Fj(J=0,1,2,3)in Eu^(3+)ions,the emission spectrum of the phosphor shows a series of narrow bands under near-ultraviolet light and the strongest peak locates at *** emission intensity of Cai-xZrO_(3):xEu^(3+)phosphor will reach the maximum as the molar concentration of Eu^(3+)is 5mol%.

关键词： diffraction narrow ultraviolet

CDA Application in Secondary ESL Class in Western China

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海外英语 2019年第4期 250-252页

作者：潘梦来广西国际商务职业技术学院对外经济贸易大学

English as second language(ESL) theoretical studies and practice have witnessed great development in recent years inChina with more schools diversifying the forms and contents of English classes over the last decade. After these years development,however, studies on ESL teaching in China, especially western China where teaching quality is relatively low and teaching resourc-es are not sufficient lags behind that in some other developed countries though some progress has been made. Students' capabilityon essential discourse analysis has not gained deserved attention. This article intends to introduce critical discourse analysis(CDA), a tool to explore discourse and social relations to secondary ESL class in western China in an attempt to find a new channelto improve students' learning effects and teaching quality of the region.

关键词： CDA secondary ESL class Western China