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Synthesis, Structure and Luminescent Property of a Zinc(Ⅱ) Coordination Polymer Incorporating Flexible Cyclohexane-1,2,3,4,5,6-hexacarboxylate Ligand

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Chemical Research in Chinese Universities 2011年第3期27卷 354-357页

作者： WANG jind LIU zhao-qing SU ting-ting School of Chemistry and Chemical Engineering Guangzhou University Guangzhou 510006 P. R. China

The hydrothermal reaction of Zn（NO3）2·4H2O, cyclohexane-1,2,3,4,5,6-hexacarboxylic acid hydrate （H6LI·H2O, cis-conformation LI： a,e,a,e,a,e） and 2,2＇-bpy yielded a new coordination polymer [Zn2（H2LII）（2,2＇-bpy）]·2H2O（trans-conformation LII： e,e,e,e,e,e）, which was characterized by single-crystal X-ray diffraction, elemental analysis, IR and XRPD（X-ray powder diffraction）. This complex crystallized in the triclinic system, with P1 space group and parameters a=0.66922（5） nm, b=0.97291（8） nm, c=1.22184（9） nm, α=99.0020（10）°, β=99.1300（10）°, γ=99.1910（10）°, V= 0.76176（10） nm3 and Z=2. The structure is a three-dimensional supramolecular network based on linear coordination chains through π-π stacking and hydrogen bonding interactions. The confromation of the starting ligand H6LI transfromed to the H2LII. The complex emits strong luminescence at room temperature.

关键词： Coordination polymer Cyclohexane-1 2 3 4 5 6-hexacarboxylate Conformation Luminescent property

Plant growth,antioxidative enzyme,and cadmium tolerance responses to cadmium stress in Canna orchioides

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Horticultural Plant Journal 2021年第3期7卷 256-266页

作者： Wen’e Zhang Xuejun Pan Qian zhao ting zhao College of Agriculture Guizhou UniversityGuiyang 550025China Key Laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region(Ministry of Education) Guiyang 550025China

The cadmium tolerance capacity of Canna orchioides was evaluated using glasshouse experiment to lay a theoretical foundation to broad applications of this species in cadmium(Cd)polluted *** plant growth,Cd absorption,and antioxidative enzyme activities of canna plants treated with different Cd concentrations(0,100,and 200mg·kg^(-1)per dry soil)for 30 days were *** results indicated that the growth of roots,leaves and stems was restricted following Cd *** bio-concentration factor was the highest in the roots,followed by the leaves,rhizomes,and *** with the control,the translocation factor decreased sharply after 100mg·kg^(-1)or 200mg·kg^(-1)Cd treatment,whereas the tolerance index decreased significantly under 200mg·kg^(-1)Cd *** Cd accumulation rate and total Cd accumulation significantly increased under 200mg·kg^(-1)Cd treatment than the *** content remained unchanged at different Cd concentrations,while the relative electrical conductivity of the root increased significantly following 200mg·kg^(-1)Cd *** stress increased significantly the activity of superoxide dismutase(SOD),peroxidase(POD),and ascorbate peroxidase(APX)in the leaves,whereas only SOD was raised in the *** catalase(CAT)and POD activity in the roots did not differ significantly at different Cd ***,APX in the roots decreased significantly under Cd stress,which suggests that the protective mechanisms in the leaves differ from those in the *** results indicated that *** has a high tolerance for ***,the reactive oxygen species caused by Cd stress could be effectively scavenged by the antioxidative *** present study proved that *** constitutes a promising ornamental plant for use in the restoration of areas contaminated with Cd.

关键词： Canna orchioides Cadmium tolerance Antioxidant Phytoremediation translocation

Congestion warning method based on the Internet of vehicles and community discovery of complex networks

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The Journal of China Universities of Posts and Telecommunications 2016年第4期23卷 37-45页

作者： zhao ting Wang Bin Gao Qi School of Automation Beijing Institute of Technology

The traffic congestion occurs frequently in urban areas, while most existing solutions only take effects after congesting. In this paper, a congestion warning method is proposed based on the Internet of vehicles（IOV） and community discovery of complex networks. The communities in complex network model of traffic flow reflect the local aggregation of vehicles in the traffic system, and it is used to predict the upcoming congestion. The real-time information of vehicles on the roads is obtained from the IOV, which includes the locations, speeds and orientations of vehicles. Then the vehicles are mapped into nodes of network, the links between nodes are determined by the correlations between vehicles in terms of location and speed. The complex network model of traffic flow is hereby established. The communities in this complex network are discovered by fast Newman（FN） algorithm, and the congestion warnings are generated according to the communities selected by scale and density. This method can detect the tendency of traffic aggregation and provide warnings before congestion occurs. The simulations show that the method proposed in this paper is effective and practicable, and makes it possible to take action before traffic congestion.

关键词： IOV complex network community discovery congestion warning

Enhanced wear resistance of NiTi alloy by surface modification with Nb ion implantation

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Rare Metals 2014年第3期33卷 244-248页

作者： Yan Li Fei Zhang ting-ting zhao Ming Tang Yong Liu School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing Key Laboratory for Advanced Functional Materials andThin Film Technology Beijing University of Aeronautics and Astronautics Key Laboratory of Aerospace Advanced Materials and Performance (Beijing University of Aeronautics and Astronautics) Ministry of Education School of Mechanical and Aerospace Engineering Nanyang Technological University

Niobium ion implantation is found to significantly decrease the friction coefficient and improve wear resistance of NiTi shape memory alloy. Scanning electron microscope（SEM） observations indicate that surface grooves formed on NiTi during the mechanical polishing are removed after Nb ion implantation. Dry friction tests show that Nb implanted NiTi samples exhibit a lower friction coefficient, narrower wear tracks, fewer wear debris generated, 46 %-62 % reduction in wear width, and29 %-49 % reduction in wear depth compared with the untreated NiTi. Wear resistance is related to the incident parameters, and the Nb implanted NiTi with the incident dose of 2.5 9 1017ionsácm-2, and incident current of2 mA behaves the best wear performance. The lubricating of Nb2O5, good oxidation resistance of Nb in NiTi, and increased micro-hardness of NiTi are responsible for the enhanced wear resistance.

关键词： NiTi Nb Ion implantation Nano-film Wear

Histone modifications and their regulatory roles in plant development and environmental memory

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Journal of Genetics and Genomics 2019年第10期46卷 467-476页

作者： ting zhao Zhenping Zhan Danhua Jiang State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyThe Innovative Academy of Seed DesignChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100101China

Plants grow in dynamic environments where they receive diverse environmental *** and precise control of gene expression is essential for plants to align their development and metabolism with fluctuating *** on histones serve as histone code" to specify chromatin and gene *** modifications execute distinct functions on the chromatin,promoting either active transcription or gene *** writers,erasers,and readers mediate the regulation of histone modifications by catalyzing,removing,and recognizing modifications,*** evidence indicates the important function of histone modifications in plant development and environmental *** modifications also serve as environmental memory for plants to adapt to environmental *** we review recent progress on the regulation of histone modifications in plants,the impact of histone modifications on environment-controlled developmental transitions including germination and flowering,and the role of histone modifications in environmental memory.

关键词： Histone modification Transcription Germination Flowering Plant-environmental response Environmental memory

Effect of La_(2)Sn_(2)O_(7)content on Ag-La_(2)Sn_(2)O_(7)/SnO_(2)arc erosion behavior and mechanism

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Journal of Rare Earths 2022年第9期40卷 1488-1498,I0006页

作者： Mengli Cao Yi Feng Lili Wang ting zhao Hao zhao Zijue Zhou School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China

La_(2)Sn_(2)O_(7)/SnO_(2)powder was synthesized by chemical co-precipitation method,and Ag-La_(2)Sn_(2)O_(7)/SnO_(2)composites were prepared by hot-pressing *** electrical resistivity,density,Brinell hardness and flexural strength of Ag-La_(2)Sn_(2)O_(7)/SnO_(2)composites were ***,the effect of La_(2)Sn_(2)O_(7)content on the arc erosion behavior of Ag-La_(2)Sn_(2)O_(7)/SnO_(2)composites at 7 kV voltage was *** the increase of La_(2)Sn_(2)O_(7)content,the arc duration and arc energy decrease,and the breakdown strength *** surface morphology of Ag-La_(2)Sn_(2)O_(2)/SnO_(2)composites after arc erosion was investigated using scanning electron microscopy and three-dimensio nal laser confocal scanning *** the increase of La_(2)Sn_(2)O_(7)content,the smaller the erosion damage,the better the anti-arc erosion ***,too much La_(2)Sn_(2)O_(7)results in the decrease of Ag-La_(2)Sn_(2)O_(7)/SnO_(2)properties and severe arc erosion.X-ray photoelectron spectroscopy was used to determine the composition of the erosion *** effect of La_(2)Sn_(2)O_(7)on wettability between Ag and SnO_(2)was investigated,and the erosion mechanism of Ag-La_(2)Sn_(2)O_(7)/SnO_(2)composites was discussed *** study can provide a reference for the application of Ag matrix electrical contact materials in high-voltage electrical appliances.

关键词： Ag-La_(2)Sn_(2)O_(7)/SnO_(2)composites Arc erosion behavior Erosion mechanism Rare earths

Fast Cycle Structure Detection for Power Grids Based on Graph Computing

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2204-2213页

作者： Xinqiao Wang Kewen Liu Weijiang Lu ting zhao Baohua zhao Xiaoming Liu the Computing&Application Technology Research Division Global Energy Interconnection Research InstituteBeijing 102209China

The cycle structure in a power grid may lower the stability of the network;thus,it is of great significance to accu-rately and timely detect cycles in power grid ***,detecting possible cycles in a large-scale network can be highly time consuming and computationally *** addition,since the power grid's topology changes over time,cycles can appear and disappear,and it can be difficult to monitor them in real *** traditional computing systems,cycle detection requires considerable computational resources,making real-time cycle detection in large-scale power grids an impossible *** computing has shown excellent performance in many areas and has solved many practical graph-related problems,such as power flow calculation and state *** this article,a cycle detection method,the Paton method,is implemented and optimized on a graph computing *** cases are used to test its performance in an actual power grid topology *** results show that the graph computing-based Paton method reduces the time consumption by at least 60%compared to that of other methods.

关键词： Cycle detection graph computing power grid distribution grid

Deep Eutectic Solvent-assisted Synthesis of Nitrogen-doped Carbon Quantum Dots for Cell Imaging

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Chemical Research in Chinese Universities 2020年第5期36卷 955-961页

作者： LI Long HUANG Yan zhao Pei MIAO Haochi zhao ting School of Chemistry and Chemical Engineenng Jiangsu UniversityZhenjiang 212013P.R.China

Carbon quantum dots(CQDs)are widely used in fluorescence imaging due to their negligible toxicity,low-cost and excellent Huorescence *** fluorescence properties of CQDs are greatly a fleeted by the synthesis method,passivation agent and reaction *** this study,the nitrogen-doped CQDs(N-CQDs)were synthesized by a facile microwave-assisted method with citric acid(CA)as a carbon source and deep eutectic solvents as a N-dopaiit as well as the reaction *** detailed characterizations,the as-prepared N-CQDs exliibited near spherical morphology with an average size of(2.64±0.55)***,the abundant hydrophilic limctional groups including hydroxyl,carboxyl,amine and quaternary-ammonium were present on the surface of the ***-CQDs displayed the excitation-dependent fluorescence feature under the excitation wavelength of 350—80 ***,the N-CQDs could be efficiently uptaken by RAW264.7 cells and emitted bright green ***,the resultant N-CQDs showed the low cytotoxicity in living cells,suggesting the great potential in bio-imaging applications.

关键词： N-Dopant carbon quantum dot Microwave Deep eutectic solvent Green light emission Cell imaging

Effect of thermal oxidation on the surface characteristics and corrosion behavior of a Ta-implanted Ti-50.6Ni shape memory alloy

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International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1134-1141页

作者： Sheng-nan Wang Yan Li ting-ting zhao School of Materials Science and Engineering Beihang University Beijhag 100191 China Beijing Key Laboratory for Advanced Functional Materials and Thin Film Technology Beihang University Beijing 100191 China Key Laboratory of Aerospace Materials and Performance (Ministry of Education) Beihang University Beijing 100191 China

A NiTi shape memory alloy （SMA） modified by Ta ion implantation was subjected to oxidation treatment in air at 723 and 873 K. Atomic force microscopy （AFM）, Auger electron spectroscopy （AES）, and grazing incidence X-ray diffraction （GIXRD） measurements were conducted to investigate the surface characteristics, including surface topography, elemental depth profiles, and surface phase structures. The surface roughness of the Ta-implanted NiTi increases after oxidation, and the higher the oxidation temperature is, the larger the value is. The surface of the Ta-implanted NiTi oxidized at 723 K is a nanolayer mainly composed of TiO2/Ta2O5 and TiO with depressed Ni content. The Ta-implanted NiTi oxidized at 873 K is mainly covered by rutile TiO2 in several micrometers of thickness. Potentiodynamic polarization tests indicated that the corrosion resistance of the Ta-implanted NiTi was improved after thermal oxidation at 723 K, but a negative impact was found for the Ta-implanted NiTi oxidized at 873 K.

关键词： nickel alloys titanium alloys shape memory effect ion implantation oxidation corrosion resistance