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Science China(Physics,Mechanics & Astronomy) 2014年第12期57卷 2259-2265页

作者： liu Yi Min liu Rong wan Department of Physics Shaoguan University

A potentially practical scheme is proposed to realize optical quantum simulation of artificial Abelian gauge field in a scalable architecture consisting of cold atomic ensembles with optical *** the present model,the collective excitations of cold atomic ensembles can be converted to the bosonic modes within the low-excitation limit,where the structure of two-dimension(2D)square plaquette enables the polaritons to move like a charged particle subjected to an external magnetic *** find that the energy spectrum of this hybrid system exhibits a shape of Hofstadter *** work provides a different perspective to the quantum simulation of condensed matter and many-body physics in the context of cavity quantum *** experimental feasibility are justified using the existing techniques.

关键词： gauge field quantum information processing cavity array

Changes in Soil Biota Resulting from Growth of the Invasive Weed, Ambrosia artemisiifolia L.(Compositae), Enhance Its Success and Reduce Growth of Co-Occurring Plants

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Journal of Integrative Agriculture 2014年第9期13卷 1962-1971页

作者： LI Hui-na XIAO Bo liu wan-xue wan Fang-hao State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

Exotic plant invasion presents a serious threat to native ecosystem structure and function. Little is known about the role of soil microbial communities in facilitating or resisting the spread of invasive plants into native communities. The purpose of this research is to understand how the invasive annual plant Ambrosia artemisiifolia L. facilitates its competition capacity through changing the structure and function of soil microbial communities. The soil characteristics of different areas invaded by A. artemisiifolia were examined. Greenhouse experiments were designed to assess the effect of A. artemisiifolia invasion-induced changes of soil biota on co-occurring plant growth, and on the interactions between A. artemisiifolia and three co-occurring plant species. The results showed that the soil organic C content was the highest in heavily invaded sites, the lowest in native plant sites, and intermediate in newly invaded sites. Soil available N, P and K concentrations in heavily invaded site were 2.4, 1.9 and 1.7 times higher than those in native plant soil, respectively. Soil pH decreased as A. artemisiifolia invasion intensity increased, and was lower in invaded sites（heavily invaded and newly invaded） than in native plant sites. The soil microbial community structure was clearly separated in the three types of sites, and A. artemisiifolia invasion increased anaerobe, sulfate-reducing bacteria and actinomycete abundance. Soil biota of invaded sites inhibits growth of co-occurring plants（Galinsoga parvifloraCav., Medicago sativa L. and Setaria plicata（Lam.） T. Cooke.） compared to soil biota from un-invaded sites, but facilitates A. artemisiifolia growth and competition with co-occurring plants. A. artemisiifolia biomass was 50-130% greater when competing with three co-occurring plants, compared to single-species competition only（invasion by A. artemisiifolia alone）, in heavily invaded soil. Results of the present study indicated that A. artemisiifolia invasion al

关键词： biological invasion invasive alien plant Ambrosia artemisiifolia L. soil biota soil fertility

A Fluorescence Optical Fiber Sensor for Amrinon Using a New Oxazole Compound

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Chemical Research in Chinese Universities 1999年第4期15卷 322-328页

作者： wanG Ying liu wan hui College of Chemistry and Chemical Engineering Southwest China Normal UniversityChongqing 400715P.R.China Analytical Center Yantai UniversityYantai 264005P.R.China)(Received Feb.81998

A new oxazole compound, 1,4 bis(naphtho[1,2 d][1,3]oxazol 2 yl)benzene(BNOB) was synthesized and incorporated into a thin plasticized polymeric membrane for sensing Amrinon. The sensor exhibits a linear response to Amrinon in the range of 7 98×10 -7 —1 52×10 -4 mol/L at pH 3 28—4 04. The response mainly originates from the Primary Inner Filter Effect, which causes a decrease in the fluorescence intensity of the sensor membrane. The distinct advantages of the proposed sensor are of full reversibility, high sensitivity and selectivity as well as short response time(<1 min), indicating that the sensor can be used to monitor Amrinon in serum samples.

关键词： 1,4-Bis(naphtho[1,2-d]oxazol-2-yl)benzene Amrinon Fluorescence optical fiber sensor

Neuroregeneration and functional recovery after stroke: advancing neural stem cell therapy toward clinical application

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Neural Regeneration Research 2021年第1期16卷 80-92页

作者： Yang Jiao Yu-wan liu Wei-Gong Chen Jing liu Stem Cell Clinical Research Center National Joint Engineering LaboratoryRegenerative Medicine CenterThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cells and Precision Medicine DalianLiaoning ProvinceChina

Stroke is a main cause of death and disability *** ability of the brain to selfrepair in the acute and chronic phases after stroke is minimal;however,promising stem cell-based interventions are emerging that may give substantial and possibly complete recovery of brain function after *** animal models and clinical trials have demonstrated that neural stem cells(NSCs)in the central nervous system can orchestrate neurological repair through nerve regeneration,neuron polarization,axon pruning,neurite outgrowth,repair of myelin,and remodeling of the microenvironment and brain *** with other types of stem cells,NSCs have unique advantages in cell replacement,paracrine action,inflammatory regulation and *** review summarizes NSC origins,characteristics,therapeutic mechanisms and repair processes,then highlights current research findings and clinical evidence for NSC *** results may be helpful to inform the direction of future stroke research and to guide clinical decision-making.

关键词： brain central nervous system cognitive impairment neurological function plasticity recovery regeneration stem cells stroke

Synthesis and Structural Characterization of Di(2-amino-5-methyl-1,8-naphthyridin-1-ium-7-carboxylato)dichlorocuprate(Ⅱ) Dihydrate

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Chinese Journal of Structural Chemistry 2007年第3期26卷 287-290页

作者： JIN Shou-Wen liu Bin CHEN wan-Zhi Department of Chemistry Zhejiang University Xixi Campus Hangzhou 310028 China

Di（2-amino-5-methyl-1,8-naphthyridin-1-ium-7-carboxylato）dichlorocuprate（Ⅱ） di- hydrate has been prepared from 5,7-dimethyl-1,8-naphthyridine-2-amine, CuCl2·2H2O and concentrated hydrochloride acid, and its structure was determined by X-ray diffraction at 298 K. The compound （C20H22Cl2CuN6O6, Mr = 576.88） crystallizes in monoclinic, space group P21/n with a = 9.102（9）, b = 12.150（12）, c = 10.619（10） A,β = 91.20°, V= 1174.1（19） A^3, Z= 2, Dc= 1.632 g/cm^3, F（000） = 590,μ = 1.208 mm^-1, R = 0.0392 and wR = 0.0984. The Cu^2＋ ion is six-coordinated by two nitrogen and two oxygen atoms from two different naphthyridine ligands at the equatorial positions together with two chloride ions located at the axial positions.

关键词： crystal structure copper chloride 5,7-dimethyi-1,8-naphthyridine-2-amine

Research on sentiment terms extraction and visualization of character sentimental interactions in A Dream of Red Mansions

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The Journal of China Universities of Posts and Telecommunications 2022年第2期29卷 24-32页

作者： Huang Pei Zhang Meng wan liu Lei Xuanzheng School of Digital Media and Design Arts Beijing University of Posts and TelecommunicationsBeijing 100876China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Network System and Network Culture Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

In the context of interdisciplinary research,using computer technology to further mine keywords in cultural texts and carry out semantic analysis can deepen the understanding of texts,and provide quantitative support and evidence for humanistic *** on the novel A Dream of Red Mansions,the automatic extraction and classification of those sentiment terms in it were realized,and detailed analysis of large-scale sentiment terms was carried *** encoder representation from transformers(BERT) pretraining and fine-tuning model was used to construct the sentiment classifier of A Dream of Red *** terms of A Dream of Red Mansions are divided into eight sentimental categories,and the relevant people in sentences are extracted according to specific *** also tries to visually display the sentimental interactions between Twelve Girls of Jinling and Jia Baoyu along with the development of the *** overall F_(1) score of BERT-based sentiment classifier reached 84.89%.The best single sentiment score reached 91.15%.Experimental results show that the classifier can satisfactorily classify the text of A Dream of Red Mansions,and the text classification and interactional analysis results can be mutually verified with the text interpretation of A dream of Red Mansions by literature experts.

关键词： A Dream of Red Mansions sentiment term extraction character sentiment interaction bidirectional encoder representation from transformers(BERT) data visualization

Estimation of the potential geographical distribution of a new potato pest(Schrankia costaestrigalis) in China under climate change

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Journal of Integrative Agriculture 2023年第8期22卷 2441-2455页

作者： XIAN Xiao-qing ZHAO Hao-xiang GUO Jian-yang ZHANG Gui-fen liu Hui liu wan-xue wan Fang-hao State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193P.R.China The National Agro-Tech Extension and Service Center Beijing 100193P.R.China

Global food security is threatened by the impacts of the spread of crop pests and changes in the complex interactions between crops and pests under climate *** costaestrigalis is a newly-reported potato pest in southern ***-warning monitoring of this insect pest could protect domestic agriculture as it has already caused regional yield reduction and/or quality decline in potato *** research aimed to confirm the potential geographical distributions(PGDs)of *** in China under different climate scenarios using an optimal MaxEnt model,and to provide baseline data for preventing agricultural damage by *** findings indicated that the accuracy of the optimal MaxEnt model was better than the default-setting model,and the minimum temperature of the coldest month,precipitation of the driest month,precipitation of the coldest quarter,and the human influence index were the variables significantly affecting the PGDs of *** highly-and moderately-suitable habitats of *** were mainly located in eastern and southern *** PGDs of *** in China will decrease under climate *** conversion of the highly-to moderately-suitable habitat will also be significant under climate *** centroid of the suitable habitat area of *** under the current climate showed a general tendency to move northeast and to the middle-high latitudes in the *** agricultural practice of plastic film mulching in potato fields will provide a favorable microclimate for *** in the suitable *** attention should be paid to the early warning and monitoring of *** in order to prevent its further spread in the main areas in China’s winter potato planting regions.

关键词： climate change potential geographical distribution crop insect pests Schrankia costaestrigalis MaxEnt model

In situ polymerization of aniline in electrospun microfibers

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Chinese Chemical Letters 2014年第1期25卷 83-86页

作者： Xiao-Qiang Li wan-wan liu Shui-Ping liu Meng-Juan Li Yong-Gui Li Ming-Qiao Ge Key Laboratory of Eco-textiles Ministry of EducationJiangnan University College of Textile & Clothing Jiangnan University

Conductive microfibers with an average diameter of ca. 1.0 μm were prepared by in situ polymerization of aniline, in which poly（vinylchloride-acrylonitrile）（PVC-AN） was used as the filament-material in electrospinning to form precursor microfibers and carry the aniline monomers. Fourier-transform infrared （FTIR） results demonstrated that PANi was successfully polymerized in the microfibers. The morphology of the PVC-AN-PANi microfibers was observed by scanning electron microscopy （SEM）. Results of differential scanning calorimetry indicated that the polymer composite of PVC-AN-PANi formed via molecular interactions. Although the conductivity of PVC-AN-PANi microfibers was still limited （2.2 × 10^-8 S/cm）, this method provided an effective and convenient approach for preparing highly uniform and soft microfibrous electrodes.

关键词： Conductive microfibers Electrospinning Polymer composite Polyaniline

First preparation of a novel polyol resin for purifying arylboronic acids

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Chinese Chemical Letters 2012年第9期23卷 993-995页

作者： Fu Long liu Sheng Biao wan Tao Jiang Key Laboratory of Marine Drugs Chinese Ministry of Education Shandong Provincial Key Laboratory of Glycoscience & Glycotechnology School of Medicine and Pharmacy Ocean University of China Qingdao 266003

A novel polystyrene-supported triol resin was first prepared by reaction of the Merrifield resin with trometamol. Using this resin, arylboronic acids were efficiently isolated and purified through a ＂capture-release＂ procedure in organic solvents. However, in basic aqueous solvents arylboronic acids were immobilized on the resin only with low yield. 2012 Tao Jiang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Polystyrene-supported polyol resin Arylboronic acid Immobilization

Pd(OAc)2 catalyzed synthesis of heteroaryl-substituted 1,8-naphthyridine derivatives via C-N-coupling reactions of chloronaphthyridines

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Chinese Chemical Letters 2007年第4期18卷 383-386页

作者： Shou Wen Jin Bin liu wan Zhi Chen Department of Chemistry Zhejiang University Xixi Campus Hangzhou 310028 China

An efficient route to synthesize the heteroaryl-substituted 1,8-naphthyridine derivatives was described. Eight 2-heteroaryl- and 2,7-diheteroaryl-1,8-naphthyridine derivatives were obtained through palladium-catalyzed C-N-coupling reactions of chloronaphthyridines with imidazole, benzimidazole, morpholine, 3,5-dimethylpyrazole, and phthalimide in moderate to good yields.

关键词： Palladium Naphthyridine C-N-coupling reaction Catalyst