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Plant-pollinator interactions in a biodiverse meadow are rather stable and tight for 3 consecutive years

Integrative Zoology 2016年第3期11卷 199-206页

作者： Qiang fang huangquan huang College of Agriculture Henan University of Science and TechnologyLuoyangChina Institute of Evolution&Ecology School of Life SciencesCentral China Normal UniversityWuhanChina

Plant-pollinator interactions can be highly variable across years in natural *** variation in the species composition and its basic structure has been investigated to understand the dynamic nature of pollination networks,little is known about the temporal dynamic of interaction strength between the same plant and pollinator species in any natural ***-mediated selection on the evolution of floral traits could be diminished if plant-pollinator interactions vary *** quantify the temporal variation in plant-pollinator interactions and the interaction strength(observed visits),we compared weighted networks between plants and pollinators in a biodiverse alpine meadow in Shangri-La,southwest China for 3 consecutive *** plant-pollinator interactions were highly dynamic such that identical interactions only accounted for 10.7%of the total between pair years,the diversity of interactions was *** identical interactions contributed 41.2%of total visits and were similar in strength and weighted *** plant species,72.6%of species were visited by identical pollinator species between pair years,accounting for over half of the total visits and three-quarters at the functional group *** generalized pollinators contributed more connectiveness and were more central in networks across ***,there was no similar or even opposite trend for plant species,which suggested that specialized plant species may also be central in pollinator *** variation in pollinator composition decreased as pollinator species numbers increased,suggesting that generalized plants experienced stable pollinator *** stable,tight interactions between generalized pollinators and specialized plants represent cornerstones of the studied community.

关键词： interaction strength plant-pollinator interaction quantitative network temporal variation turnover

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Vegetation Change of Ecotone in West of Northeast China Plain Using Time-series Remote Sensing Data

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Chinese Geographical Science 2010年第2期20卷 167-175页

作者： huang fang WANG Ping School of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China

Multi-temporal series of satellite SPOT-VEGETATION normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) data from 1998 to 2007 were used for analyzing vegetation change of the ecotone in the west of the Northeast China Plain. The yearly and monthly maximal values,anomalies and change rates of NDVI and NDWI were calculated to reveal the interannual and seasonal changes in vegetation cover and vegetation water content. Linear regression method was adopted to characterize the trends in vegetation change. The yearly maximal NDVI decreased from 0.41 in 1998 to 0.37 in 2007,implying the decreasing trend of vegetation activity. There was a significant decrease of maximal NDVI in spring and summer over the study period,while an increase trend was observed in autumn. The vegetation-improved regions and vegetation-degraded regions occupied 17.03% and 20.30% of the study area,respectively. The maximal NDWI over growing season dropped by 0.027 in 1998–2007,and about 15.15% of the study area showed a decreasing trend of water content. Vegetation water stress in autumn was better than that in spring. Vegetation cover and water content variations were sensitive to annual precipitation,autumn precipitation and summer temperature. The vegetation degradation trend in this ecotone might be induced by the warm-drying climate especially continuous spring and summer drought in the recent ten years.

关键词： vegetation change normalized difference vegetation index (NDVI) normalized difference water index (NDWI) SPOT-VEGETATION ecotone Northeast China Plain

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Synthesis,Characterization and Structure of Chiral Amino Acids and Their Corresponding Amino Alcohols with Camphoric Backbone

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1243-1249页

作者： QIAN hui-Fen huang Wei LI hui-hui YAO Cheng College of Sciences Nanjing University of Technology Nanjing 210009 China State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-（＋）-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among them, one intermediate （1S,3R）-3-amino-2,2,3- trimethyl cyclopentane-1-carboxylic acid hydrochloride 3 was structurally elucidated by X-ray diffraction techniques. Versatile intermolecular hydrogen bonding interactions observed in its packing structure result in a two-dimensional framework.

关键词： chiral amino acids and amino alcohols (1S,3R)-3-amino-2,2,3-trimethyl-cyclopentane-1-carboxylic acid hydrochloride hydrogen-bonding interactions crystal structures

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Structure of MgSO_4 in Concentrated Aqueous Solutions by X-Ray Diffraction

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Chemical Research in Chinese Universities 2011年第3期27卷 490-495页

作者： CAO Ling-di fang Yah fang Chun-hui Key Laboratory of Salt Resources and Chemistry Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 P. R. China＂ Graduate School of Chinese Academy of Sciences Beijing 100049 P. R. China

Detailed time-and-space-averaged structure of MgSO4 in the concentrated aqueous solutions was investigated via X-ray diffraction with an X’pert Pro θ-θ diffractometer at 298 K, yielding structural function and radial distribution function（RDF）. The developed KURVLR program was employed for the theoretical investigation in consideration of the ionic hydration and ion association. Multi-peaks Gaussian fitting method was applied to deconvolving the overlapping bands of Differential radial distribution function（DRDF）. The calculation of the geometric model shows that octahedrally six-coordinated Mg（H2O）62＋, with an Mg2＋…OW bond length of 0.201 nm dominates in the solutions. There exists contact ion-pair（CIP） in the more concentrated solution（1：18, H2O/salt molar ratio） with a coordination number of 0.8 and a characteristic Mg…S distance of 0.340 nm. The result indicates the hydrated SO42– ion happens in the solution. The S…OW bond distance was determined to be 0.382 nm with a coordination number of 13. The fraction of CIP increases significantly with the increasing concentration. The symmetry of the hydration structure of sulfate ion is lowered by forming complex with magnesium ion.

关键词： Solution structure X-Ray diffraction Magnesium sulfate Radial distribution function(RDF)

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Effects of land use change on the spatiotemporal variability of soil organic carbon in an urban-rural ecotone of Beijing,China

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Journal of Integrative Agriculture 2016年第4期15卷 918-928页

作者： YE hui-chun huang Yuan-fang CHEN Peng-fei huang Wen-jiang ZHANG Shi-wen huangShan-yu HOU Sen Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100094P.R.China Hainan Key Laboratory of Earth Observation Sanya 572029P.R.China College of Resources and Environment China Agricultural UniversityBeijing 100193P.R.China State Key Laboratory of Resources and Environment Information System Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China College of Earth and Environment Anhui University of Science and TechnologyHuainan 232001P.R.China Institute of Geography University of CologneKoln 50923Germany

Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon （SOC） can provide guidance for low carbon and sustainable agriculture. In this paper, based on the large-scale datasets of soil surveys in 1982 and 2009 for Pinggu District -- an urban-rural ecotone of Beijing, China, the effects of land use and land use changes on both temporal variation and spatial variation of SOC were analyzed. Results showed that from 1982 to 2009 in Pinggu District, the following land use change mainly occurred： Grain cropland converted to orchard or vegetable land, and grassland converted to forestland. The SOC content decreased in region where the land use type changed to grain cropland （e.g., vegetable land to grain cropland decreased by 0.7 g kg-1; orchard to grain cropland decreased by 0.2 g kg-l）. In contrast, the SOC content increased in region where the land use type changed to either orchard （excluding forestland） or forestland （e.g., grain cropland to orchard and forestland increased by 2.7 and 2.4 g kg-1, respectively; grassland to orchard and forestland increased by 4.8 and 4.9 g kg-1, respectively）. The organic carbon accumulation capacity per unit mass of the soil increased in the following order： grain cropland soil〈vegetable land/grassland soil〈orchard soil〈forestland soil. Therefore, to both secure supply of agricultural products and develop low carbon agriculture in a modern city, orchard has proven to be a good choice for land using.

关键词： land use change soil organic carbon spatiotemporal variability urban-rural ecotone

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Microstructures of Ti–Ni–Fe wire after severe cold-drawing and annealing

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Rare Metals 2013年第6期32卷 550-554页

作者： hui-fang Geng Fu-Shun Liu School of Material Science and Engineering Beijing University of Aeronautics and Astronatics

The microstructures and mechanical properties of Ti–47 at%Ni–3 at%Fe shape memory alloy wire under the condition of severe cold-drawing at room temperature and different postdeformation annealing processes were intensively investigated using transmission electron microscope(TEM),X-ray diffraction(XRD),Vickers microhardness tester and electron tensile *** is indicated that the structure of the alloy evolves into a predominant amorphous structure with a trace of nanocrystalline B2 phase after the cold-drawing of 76%areal *** annealing process exerted significant influence on the microstructure and mechanical *** occurs when the cold-drawn wire was annealed at 300℃ for 30 *** ultimate tensile strength and ductility as well as the superelasticity of the wire are improved significantly by cold-drawing plus postdeformation annealing.

关键词： Ti–Ni–Fe wire Severe plastic deformation Cold-drawing Annealing Amorphous structure

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Prevalence of antifolate drug resistance markers in Plasmodium vivax in China

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Frontiers of Medicine 2022年第1期16卷 83-92页

作者： fang huang Yanwen Cui He Yan hui Liu Xiangrui Guo Guangze Wang Shuisen Zhou Zhigui Xia National Institute of Parasitic Diseases Chinese Center for Disease Control and PreventionChinese Center for Tropical Diseases ResearchWHO Collaborating Center for Tropical DiseasesNational Centre for International Research on Tropical DiseasesNHC Key Laboratory of Parasite and Vector Biology(National Institute of Parasitic DiseasesChinese Center for Disease Control and Prevention)Shanghai 200025China Yunnan Institute of Parasitic Diseases Puer 665000China Yingjiang County for Disease Control and Prevention Yingjiang 679300China Hainan Center for Disease Control&Prevention Haikou 570203China

The dihydrofolate reductase(dhfr)and dihydropteroate synthetase(dhps)genes of Plasmodium vivax,as antifolate resistance-associated genes were used for drug resistance surveillance.A total of 375 *** isolates collected from different geographical locations in China in 2009–2019 were used to sequence Pvdhfr and *** majority of the isolates harbored a mutant type allele for Pvdhfr(94.5%)and Pvdhps(68.2%).The most predominant point mutations were S117T/N(77.7%)in Pvdhfr and A383G(66.8%)in *** acid changes were identified at nine residues in Pvdhfr.A quadruple-mutant haplotype at 57,58,61,and 117 was the most frequent(57.4%)among 16 distinct Pvdhfr *** in Pvdhps were detected at six codons,and the double-mutant A383G/A553G was the most prevalent(39.3%).Pvdhfr exhibited a higher mutation prevalence and greater diversity than Pvdhps in *** isolates from Yunnan carried multiple mutant haplotypes,while the majority of samples from temperate regions and Hainan Island harbored the wild type or single mutant *** study indicated that the antifolate resistance levels of *** parasites were different across China and molecular markers could be used to rapidly monitor drug *** provided evidence for updating national drug policy and treatment guidelines.

关键词： drug resistance antifolates molecular markers Plasmodium vivax China

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Blockchain-based multiple groups data sharing with anonymity and traceability

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Science China(Information Sciences) 2020年第3期63卷 7-19页

作者： hui huang Xiaofeng CHEN Jianfeng WANG State Key Laboratory of Integrated Service Networks (ISN) Xidian University College of Computer Minnan Normal University

Group data sharing enables information sharing between multiple parties for cooperative purposes. However, the existing schemes only consider scenarios in which all parties in the same organization want to share data. Achieving secure data sharing between users of different groups is also a relevant research issue. In this paper, we propose a blockchain-based data sharing scheme for multiple groups with anonymity and traceability. Owing to the consortium blockchain technique, any user in the system can easily verify the validity of the shared data without interacting with a third-party auditor. Additionally, the proposed scheme can not only enable data sharing between different groups with enhanced security anonymously but also achieve traceability and non-frameability.

关键词： multiple groups data sharing blockchain anonymity traceability

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Acceptor-acceptor-type conjugated polymer semiconductors

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Journal of Energy Chemistry 2021年第8期30卷 364-387,I0008页

作者： Dunshuai Qu Ting Qi hui huang School of Chemical Sciences University of Chinese Academy of Sciences100049 BeijingChina College of Materials Science and Opto-Electronic Technology&Center of Materials Science and Optoelectronics Engineering&CAS Center for Excellence in Topological Quantum Computation&CAS Key Laboratory of Vacuum Physic University of Chinese Academy of Sciences100049 BeijingChina

The rapid development of electronic devices such as organic field-effect transistors(OFETs)and solar cells makes the research and development of electronic transport materials *** acceptor-acceptortype(AàA-type)conjugated n-type polymer semiconductors have caught much attention due to the outstanding advantages on excellent electron-accepting capabilities,the precise adjustment of energy levels and the mass production at low fabrication *** article systematically reviews the polymerization methods of AàA-type polymers and the recent advancements applied in OFETs and polymer solar cells(PSCs).The analyses of the synthesis and the relationship between device performances and polymer molecular structures may provide a constructive guidance for the further development of highperformance n-type polymer materials.

关键词： Acceptor-acceptor-type(A-A-type) polymers Organic field-effect transistors(OFETs) Polymer solar cells(PSCs) Polymerization n-Type semiconductors

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On Hamiltonian Property of Cayley Digraphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 547-556页

作者： fang DUAN Qiong-xiang huang School of Mathematics Science Xinjiang Normal UniversityUrumqi 830017China College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830017China

Let G be a finite group generated by S and C(G,S) the Cayley digraphs of G with connection set *** this paper,we give some sufficient conditions for the existence of hamiltonian circuit in C(G,S),where G=Zm×H is a semiproduct of Zmby a subgroup H of *** particular,if m is a prime,then the Cayley digraph of G has a hamiltonian circuit unless G=Zm×*** addition,we introduce a new digraph operation,called φ-semiproduct of Γ1by Γ2and denoted by Γ1×Γ_φΓ2,in terms of mapping φ:V(Γ2)→{1,-1}.Furthermore we prove that C(Zm,{a})×_φ C(H,S) is also a Cayley digraph if φ is a homomorphism from H to{1,-1} ≤ Zm~*,which produces some classes of Cayley digraphs that have hamiltonian circuits.

关键词： Cayley digraphs hamiltonian circuit external semidirect product

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