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A systems dynamic model of a coal-based city with multiple adaptive scenarios： A case study of Ordos, China

Science China Earth Sciences 2018年第3期61卷 302-316页

作者： LIU XiaoQian PEI Tao ZHOU ChengHu DU yunyan MA Ting XIE ChuanJie XU Jun College of Arts and Science of Beijing Union University Beijing 100191 China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023 677ina

Abstract Cities based on coal resources have increasingly important social and economic roles in China. Their strategies for sustainable development, however, urgently need to be improved, which represents a huge challenge. Most observers believe that the continued progress of these cities relies on the optimization of scientific adaptive management in which social, economic, and ecological factors are incorporated. A systems perspective that combines policies, management priorities, and long-term policy impacts needs to be applied. To date, however, such an approach has not been adopted, which means it is difficult to implement adaptive management at the regional scale. In this study, we used various situations to develop a multiple adaptive scenario system dynamics model. We then simulated a range of policy scenarios, with Ordos in the Inner Mongolia Autonomous Region as a case study. Simulation results showed that the current strategy is not sustainable and predicted that the system would exceed the environmental capacity, with risks of resource exhaustion and urban decline in 2025-2035. Five critical policy variables, including the urban population carrying capacity, rates of water consumption and water recycling, and expansion of urban land cover, were identified during sensitivity analysis. We developed and compared six socio-economic scenarios. The urban area, represented by the urban population density, seemed to transition through five different stages, namely natural growth, rapid growth, stable oscillation, fading, and rebalancing. Our scenarios suggested that different policies had different roles through each stage. The water use efficiency management policy had a comprehensive far-reaching influence on the system behavior; land urbanization management functions dominated at the start, and population capacity management was a major control in the mid-term. Our results showed that the water recycling policy and the urban population carrying capacity were

关键词： System dynamics model Stella Resource-based city Multiple adaptive scenarios

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Neural network identification for underwater vehicle motion control system based on hybrid learning algorithm

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High Technology Letters 2012年第3期18卷 243-247页

作者： Sun Yushan Wang Jianguo Wan Lei Hu yunyan Jiang Chunmeng State Key Laboratory of Autonomous Underwater Vehicle Harbin Engineering University Harbin 150001 P. R. China China Ship Development and Design Center Wuhan 430064 P. R. China Humanities Department City College of Wuhan University of Science and Technology Wuhan 430083 P. R. China

Based on the structure of Elman and Jordan neural networks, a new dynamic neural network is constructed. The network can remember the past state of the hidden layer and adjust the effect of the past signal to the current value in real-time. And in order to enhance the signal processing capabilities, the feedback of output layer nodes is increased. A hybrid learning algorithm based on genetic algorithm （GA） and error back propagation algorithm （BP） is used to adjust the weight values of the network, which can accelerate the rate of convergence and avoid getting into local optimum. Finally, the improved neural network is utilized to identify underwater vehicle （UV）＇ s hydrodynamic model, and the simulation results show that the neural network based on hybrid learning algorithm can improve the learning rate of convergence and identification nrecision.

关键词： underwater vehicle (UV) system identification neural network genetic algo-rithm (GA) back propagation algorithm

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Regulation of Glucose Oxidase Activity through Interaction with Fullerene Derivatives

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Chinese Journal of Chemistry 2012年第2期30卷 418-426页

作者： Gao,yunyan Wang,Zhongli Ou,Zhize Li,Yi Wang,Xuesong Yang,Guoqiang Ministry of Education Key Laboratory of Space Applied Physics and Chemistry&Department of Applied Chemistry School of ScienceNorthwestern Polytechnical UniversityXi'anShaanxi 710072China Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China

The 2-（hydroxymethyl）pyridine modified C60 （PY-C60） and methoxydiglycol modified C60 （MDG-C60） are synthesized using Bingel-Hirsch reaction and characterized by nuclear magnetic resonance （NMR） and mass spectra. PY-C60 and MDG-C60 can bind to glucose oxidase （GOx） and quench the fluorescence of tryptophan （Trp） residue in GOx through static mechanism. The conformation of GOx is disturbed after formation of complex with these fullerene derivatives. Kinetic analysis indicates that PY-C60 and MDG-C60 may affect the catalytic activity of GOx with a partial mixed-type inhibition mechanism. In the plasma glucose concentration range （3.6--5.2 mmol·L-1）, PY-C60 may significantly accelerate the catalytic velocity of GOx, however, MDG-C60 exerts almost no obvious change to the initial velocity of GOx, suggesting that elaborate design of molecular structure of fullerene derivative is very important for regulating the biological activity of fullerene-enzyme complex.

关键词： fullerene C60 glucose oxidase partial mixed-type inhibition mechanism redox mediator electron transfer

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Effects of Mg Doping on Photoconductivity of GaN Films

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Journal of Materials Science & Technology 2003年第6期19卷 575-577页

作者： Deheng ZHANG, Qingpu WANG and yunyan LIUSchool of Physics and Microelectronics, Shandong University, Jinan 250100, China Sch. of Phys. and Microelectronics Shandong Univ. Ji'nan 250100 China

This paper presents the UV photoconductivity properties of GaN films doped with different Mg concentrations deposited by MOCVD. It was observed that for the undoped and weakly doped GaN films the UV photocurrent response was relatively large and the relax time was relatively short. With an increase in doped Mg content, the samples became p-type, the photocurrent response became weak and the relax time became longer.

关键词： GaN UV photodetector Doping MOCVD

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Cooperative effect from cation and anion of pyridine-containing anion-based ionic liquids for catalysing CO_2 transformation at ambient conditions

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Science China Chemistry 2017年第7期60卷 958-963页

作者： Guangfeng Yuan Yanfei Zhao yunyan Wu Ruipeng Li Yu Chen Dongmei Xu Zhimin Liu College of Chemical and Environmental Engineering Shandong University of Science and Technology Beijing National Laboratory for Molecular Sciences Key Laboratory of Colloid Interface and Thermodynamics Institute of ChemistryChinese Academy of Sciences

Pyridine-containing anion-based ionic liquids(PA-ILs) with two kinds of interaction sites to bind CO_2, e.g., [P4444][2-OP], were found to be highly efficient for catalysing the cycloaddition reactions of atmospheric CO_2 with epoxides at room temperature under metal-and halogen-free conditions, producing a series of cyclic carbonates in high yields. It was demonstrated that the cooperative interaction from two interaction sites in the anions of PA-ILs activated CO_2, while the cation activated the epoxides substrates via coordination to the central P+ unit, thus resulting in the high activity of the IL catalysts.

关键词： ionic liquids CO2 transformation cyclic carbonates atmospheric pressure room temperature

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Transcriptomic and metabolomic analyses of cucumber fruit peels reveal a developmental increase in terpenoid glycosides associated with age-related resistance to Phytophthora capsici

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Horticulture Research 2017年第1期4卷 266-276页

作者： Ben N Mansfeld Marivi Colle yunyan Kang A Daniel Jones Rebecca Grumet Department of Horticulture Graduate Program in Plant BreedingGenetics and BiotechnologyMichigan State UniversityEast Lansing48824MIUSA College of Horticulture South China Agricultural UniversityGuangzhou510642China Department of Biochemistry and Molecular Biology Michigan State UniversityEast Lansing48824MIUSA Department of Chemistry Michigan State UniversityEast Lansing48824MIUSA

The oomycete,Phytophthora capsici,infects cucumber(Cucumis sativus L.)*** age-related resistance(ARR)to this pathogen was previously observed in fruit of cultivar‘Vlaspik’and shown to be associated with the *** fruits are highly susceptible,but develop resistance at~10–12 days post pollination(dpp).Peels from resistant(16 dpp)versus susceptible(8 dpp)age fruit are enriched with genes associated with defense,and methanolic extracts from resistant age peels inhibit pathogen *** we compared developing fruits from‘Vlaspik’with those of‘Gy14’,a line that does not exhibit *** analysis of peels of the two lines at 8 and 16 dpp identified 80 genes that were developmentally upregulated in resistant‘Vlaspik’16 dpp versus 8 dpp,but not in susceptible‘Gy14’at 16 dpp.A large number of these genes are annotated to be associated with defense and/or specialized metabolism,including four putative resistance(R)genes,and numerous genes involved in flavonoid and terpenoid synthesis and *** metabolomic analysis was performed on extracts from 8 and 16 dpp‘Vlaspik’and‘Gy14’fruit peels using Ultra-Performance Liquid Chromatography and Quadrupole Time-of-Flight Mass *** analysis of the metabolomes identified 113 ions uniquely abundant in resistant‘Vlaspik’16 dpp peel *** most abundant compounds in this group had relative mass defects consistent with terpenoid *** of the three most abundant ions were annotated as glycosylated nor-terpenoid ***,these analyses reveal potential mechanisms by which ARR to *** may be conferred.

关键词： metabolism resistance abundant

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Blooms of Prorocentrum donghaiense reduced the species diversity of dinoflagellate community

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Acta Oceanologica Sinica 2020年第4期39卷 110-119页

作者： Huan Wang Zhangxi Hu Zhaoyang Chai yunyan Deng Zifeng Zhan Ying Zhong Tang CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Department of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Most of reported harmful algal blooms(HABs)of microalgae(75%)have been caused by *** on the negative effects of HABs have generally focused on animals,valuable organisms in particular,and environmental factors such as dissolved oxygen and nutrients,but relatively fewer on community level,particularly that using metagenomic *** this study,we reported an investigation on the effects of a HAB caused by the dinoflagellate Prorocentrum donghaiense on the species diversity and community structure of the dinoflagellate sub-community via a pyrosequencing approach for the samples taken before,during,and after the bloom season of *** in the East China *** sequenced partial 28S rRNA gene of dinoflagellates for the field samples and evaluated the species richness and diversity indices of the dinoflagellate community,as a sub-community of the total *** obtained 800185 valid sequences(categorized into 560 operational taxonomic units,OTUs)of dinoflagellates from 50 samples and found that the biodiversity of dinoflagellate community was significantly reduced during the blooming period in comparison to that in pre-and after-blooming periods,as reflected in the four diversity indices:the species richness expressed as the number of OTUs,Chao1 index,Shannon index(evenness),and Gini-Simpson *** four indices were all found to be negatively correlated to the cell density of the bloom species *** analyses also revealed that the *** cell abundance was correlated negatively with NO3--N,and NO2--N,but positively with total nitrogen(TN)and total phosphorus(TP).Principal coordinates analysis(PCoA)showed that the community structure of dinoflagellates was markedly different among the different sampling periods,while the redundancy analysis(RDA)revealed *** abundance,salinity,NO3--N,and SiO32-were the most four significant factors shaping the dinoflagellate community *** results toget

关键词： Prorocentrum donghaiense dinoflagellate community diversity pyrosequencing East China Sea

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A Novel Route to Synthesize N,N-Dimethyl Arylmethylamines from Aryl Aldehydes, Hexamethylenetetramine and Hydrogen

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Chinese Journal of Chemistry 2020年第8期38卷 842-846页

作者： Zhengang Ke Bo Yu yunyan Wu Yanfei Zhao Peng Yang Shien Guo Zhimin Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of ColloidInterface and ThermodynamicsCAS Research/Education Centre for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing 101407China

Developing simple and green routes to access valuable chemicals is of ***,we present a green and novel route to synthesize N,N-dimethyl arylmethylamines(DAMAs)from hexamethylenetetramine(HMTA)and aryl aldehydes in the presence of hydrogen,and a series of DAMAs can be obtained in good *** approach opens the precedent for HMTA as N,N-dimethylamine source to synthesize chemicals with N,N-dimethylamine group,which has promising applications for N-containing chemicals synthesis.

关键词： synthesis. amines synthesize

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OPTIMIZED MEANSHIFT TARGET REFERENCE MODEL BASED ON IMPROVED PIXEL WEIGHTING IN VISUAL TRACKING

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Journal of Electronics(China) 2013年第3期30卷 283-289页

作者： Chen Ken Song Kangkang Kyoungho Choi Guo yunyan College of Information Science and Engineering Ningbo University Department of Electronic Engineering Mokpo National University

The generic Meanshift is susceptible to interference of background pixels with the target pixels in the kernel of the reference model, which compromises the tracking performance. In this paper, we enhance the target color feature by attenuating the background color within the kernel through enlarging the pixel weightings which map to the pixels on the target. This way, the background pixel interference is largely suppressed in the color histogram in the course of constructing the target reference model. In addition, the proposed method also reduces the number of Meanshift iterations, which speeds up the algorithmic convergence. The two tests validate the proposed approach with improved tracking robustness on real-world video sequences.

关键词： Visual tracking Meanshift Color feature histogram Pixel weighting Tracking robust-hess

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N-doped carbon supported Pd catalysts for N-formylation of amines with CO2/H2

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Science China Chemistry 2018年第6期61卷 725-731页

作者： Xiaoying Luo Hongye Zhang Zhengang Ke Cailing Wu Shien Guo yunyan Wu Bo Yu Zhimin Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of Colloid Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Using mesoporous N-doped carbons(NCs)derived from glucose and melamine as the supports,a series of Pd/NC catalysts were prepared,in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the *** was indicated that the resultant Pd/NC catalysts were effective for N-formylation of amines with CO_2and H_2in ethanol without any ***,the catalyst Pd/NC-800-6.9%containing quaternary N showed the best performance,affording a series of formylamides in good or even excellent *** investigation reveals that the interaction between the Pd nanoparticles and quaternary nitrogen in the NC support was responsible for the good performance of the catalyst.

关键词： Pd/NC C–N formation N-formylation CO2 H2

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