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Response of forest distribution to past climate change: An insight into future predictions

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Chinese Science Bulletin 2013年第35期58卷 4426-4436页

作者： liu hongyan YIN Yi College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes Peking University

Vegetation dynamics could lead to changes in the global carbon and hydrology cycle,as well as feedbacks to climate *** paper reviews the response of forest dynamics to climate *** on palaeoecological studies,we summarized the features and modes of vegetation response to climate change and categorized the impacts of climate change on vegetation dynamics as three types:climate stress on vegetation,buffer effects by non-climatic factors,and perturbation of the vegetation distribution by stochastic *** to the openness of the vegetation system and the integrated effects of both climatic and non-climatic factors,the vegetation-climate relationship deviates far from its *** vegetation distribution shows a non-linear response to climate change,which also makes it difficult to quantify the modern vegetation distribution in terms of specific climatic *** analog,space-for-time-substitution and Dynamic Global Vegetation Models(DGVMs)are three approaches to predicting the future vegetation distribution,but they have all been established on the assumption of vegetation-climate *** propose that improving DGVMs is a future task for studies of vegetation dynamics because these are process-based models incorporating both disturbance(***)and the variability in Plant Functional Types(PFTs).However,palaeoecological results should be used to test the models,and issues like spatial and temporal scale,complexity of climate change,effects of non-climatic factors,vegetation-climate feedback,and human regulation on vegetation dynamics are suggested as topics for future studies.

关键词：气候变化森林分布预测非气候因素植被变化植物功能型植被分布植被动态

The LGM refugia of deciduous oak and distribution development since the LGM in China

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Science China Earth Sciences 2023年第1期66卷 80-91页

作者： Qian HAO hongyan liu Ying CHENG Zhaoliang SONG Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China School of Geography and Tourism Shaanxi Normal UniversityXi’an 710119China

The distribution development of oak has significant effects on ecosystems and ***-term forest distribution studies can help to better understand the vegetation dynamics under climate change or human activities in the *** this study,we integrated different methods(i.e.,palaeoecology,phylogeography,and species distribution models)to investigate the likely locations of glacial refugia and the postglacial development of the main deciduous oak species(i.e.,Quercus variabilis,***,***,***,*** and ***).The results indicated that mountains such as the Changbai,Qinling,and Dabie Mountains acted as the refugia in northern and central China during the Last Glacial Maximum(LGM).The present Quercus in northern China could be the result of local dispersal during the postglacial period rather than only that of long-distance migration from south to *** was the main influencing factor for oak migration,while human activities did not show much influence on this widespread *** topography acted as a buffer and made the mountains act as refugia under a deteriorated *** with other main tree genera(e.g.,Pinus and Betula),the refugia locations and migration routes of deciduous oak species were different because of their physiological *** individual migration dynamics of these three genera need to be considered when modelling their dynamics.

关键词： Quercus Pollen analysis Species distribution model Chloroplast DNA Precipitation

Synthesis, Characterization and Thermal Decomposition Mechanism of Cetyltrimethyl Ammonium Tetrathiotungstate

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Journal of Natural Gas Chemistry 2006年第2期15卷 127-133页

作者： Gaojun An Yunqi liu Yongming Chai hongyan Shang Chenguang liu State Key Laboratory of Heavy Oil Processing Key Laboratory of Catalysis CNPC China University of Petroleum Dongying 257061 China

The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate （CTriMATT） were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, X-ray diffraction （XRD）, Fourier transform infrared （FT-IR）, Ultraviolet visible （UV-Vis） spectra. The results showed that the as-synthesized CTriMATT had high purity and good crystallinity. The introduction of alkyl groups induced a shift of the stretching vibration band of W-S bond to lower wavenumber, while it had no influence on the position of WS4^2-. Thermogravimetric analysis （TG）, differential thermal analysis （DTA） and in situ XRD characterizations revealed that CTriMATT began to decompose at 423 K in nitrogen and was converted to WS2 eventually. In addition, the decomposition product of CTriMATT at 673 K in nitrogen was characterized by N2 adsorption （BET） and scanning electron microscopy （SEM）. The results demonstrated that WS2 with higher specific surface area, and pore volume could be obtained from the thermal decomposition of CTriMATT in nitrogen.

关键词： cetyltrimethyl ammonium tetrathiotungstate synthesis characterization thermal decomposition mechanism alkyl-substituted

Dual-functional conductive nanofilm absorber

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Nano Research 2023年第12期16卷 13375-13380页

作者： hongyan liu Zheng Xie Weiming liu Hongdong Li Yue Yan Xiaoli Wang Beijing Institute of Aeronautical Materials Beijing 100095China College of Rare Earth and Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Converting solar energy by to other forms of energy has attracted a lot of interest from academy to ***,the overall utilization efficiency of solar energy is inferior due to the limited effective solar spectrum ***,in order to utilize the broadband solar spectrum more efficiently,a novel hybrid absorber structure was proposed,which consists of a four-layer planar nanofilm with dual functions of heat absorption and *** average absorption in the visible range is larger than 0.95,and in the near-infrared spectral region,the average absorption is still larger than *** overall absorption of the absorber is over 0.86,while the thermal emittance is lower than 0.04,which can lead to remarkable thermal utilization ***,the full range of the solar irradiance can be utilized by incorporating the photocatalytic TiO_(2) layer into the absorber,which is active in the ultraviolet spectral *** addition to the broadband spectral usage,the virtues of inexpensiveness and environmental friendliness make it a facile alternative to be applied in solar energy transformation.

关键词： absorber photocatalysis multilayer film heat

Targeting cIAPs,a New Option for Functional Cure of Chronic Hepatitis B Infection?

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Virologica Sinica 2018年第5期33卷 459-461页

作者： hongyan liu Jinlin Hou Xiaoyong Zhang State Key Laboratory of Organ Failure Research Guangdong Provincial Key Laboratory of Viral Hepatitis ResearchDepartment of Infectious Diseases Nanfang HospitalSouthern Medical University

Hepatitis B virus (HBV)infection causes a wide spectrum of liver diseases in more than 240million people worldwide (Ott et al.2012).Patients with chronic hepatitis B (CHB)may progress to HBV-related end-stage liver di... 详细信息

关键词： Chronic Hepatitis B Infection cIAPs

The origin and evolution of carpels and fruits from an evo-devo perspective

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Journal of Integrative Plant Biology 2023年第2期65卷 283-298页

作者： hongyan liu Jun Li Pichang Gong Chaoying He State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China The Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100101China

The flower is an evolutionary innovation in angiosperms that drives the evolution of *** carpel is integral to a flower and develops into fruits after fertilization,while the perianth,consisting of the calyx and corolla,is decorative to facilitate pollination and protect the internal organs,including the carpels and ***,the nature of flower origin is carpel and stamen origin,which represents one of the greatest and fundamental unresolved issues in plant evolutionary ***,we briefly summarize the main progress and key genes identified for understanding floral development,focusing on the origin and development of the *** ABC models have played pioneering roles in elucidating flower development,but remain insufficient for resolving flower and carpel *** genetic basis for carpel origin and subsequent diversification leading to fruit diversity also remains *** on current research progress and technological advances,simplified floral models and integrative evolutionary-developmental(evodevo)strategies are proposed for elucidating the genetics of carpel origin and fruit *** birth of a few master regulatory genes and subsequent functional diversification might play a pivotal role in these evolutionary *** the identified transcription factors,AGAMOUS(AG)and CRABS CLAW(CRC)may be the two core regulatory genes for carpel origin as they determine carpel organ identity,determinacy,and ***,a comparative identification of their protein-protein interactions and downstream target genes between flowering and non-flowering plants from an evo-devo perspective may be primary projects for elucidating carpel origin and development.

关键词： AGAMOUS CRABS CLAW carpel origin evo-devo floral development fruit evolution

An anisotropic Chebyshev descriptor and its optimization for deformable shape correspondence

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Computational Visual Media 2023年第3期9卷 461-477页

作者： Shengjun liu hongyan liu Wang Chen Dong-Ming Yan Ling Hu Xinru liu Qinsong Li School of Mathematics and Statistics Central South UniversityChangsha 410000China State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 101408China School of Mathematics and Statistics Hunan First Normal UniversityChangsha 410000China Big Data Institute Central South UniversityChangsha 410000China

Shape descriptors have recently gained popularity in shape matching,statistical shape modeling,*** discriminative ability and efficiency play a decisive role in these *** this paper,we first propose a novel handcrafted anisotropic spectral descriptor using Chebyshev polynomials,called the anisotropic Chebyshev descriptor(ACD);it can effectively capture shape features in multiple *** ACD inherits many good characteristics of spectral descriptors,such as being intrinsic,robust to changes in surface discretization,***,due to the orthogonality of Chebyshev polynomials,the ACD is compact and can disambiguate intrinsic symmetry sinces everal directions are *** improve the ACD’s discrimination ability,we construct a Chebyshev spectral manifold convolutional neural network(CSMCNN)that optimizes the ACD and produces a learned *** experimental results show that the ACD outperforms existing state-of-the-art handcrafted *** combination of the ACD and the CSMCNN is better than other state-of-the-art learned descriptors in terms of discrimination,efficiency,and robustness to changes in shape resolution and discretization.

关键词： anisotropic descriptor spectral descriptor shape descriptor shape matching spectral convolution deep learning

A DFT theoretical study of CH_4 dissociation on gold-alloyed Ni(111)surface

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Journal of Natural Gas Chemistry 2011年第6期20卷 611-617页

作者： hongyan liu Ruixia Yan Riguang Zhang Baojun Wang Kechang Xie Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 Shanxi China College of Chemistry and Chemical Engineering Shanxi Datong University Datong 037009 Shanxi China

A density-functional theory（DFT）method has been conducted to systematically investigate the adsorption of CHx（x=0～4）as well as the dissociation of CHx（x=1～4）on（111）facets of gold-alloyed Ni *** results have been compared with those obtained on pure Ni（111）*** shows that the adsorption energies of CHx（x=1～3）are lower,and the reaction barriers of CH4 dissociation are higher in the first and the fourth steps on gold-alloyed Ni（111）compared with those on pure Ni（111）.In particular,the rate-determining step for CH4 dissociation is considered as the first step of dehydrogenation on gold-alloyed Ni（111）,while it is the fourth step of dehydrogenation on pure Ni（111）.Furthermore,the activation barrier in rate-determining step is higher by 0.41 eV on gold-alloyed Ni（111）than that on pure Ni（111）.From above results,it can be concluded that carbon is not easy to form on gold-alloyed Ni（111）compared with that on pure Ni（111）.

关键词： adsorption CH4 dissociation reaction barrier d-band center

Comparison of two design methods of aerodynamic biobjectives for airfoil and wing shapes

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Science China(Technological Sciences) 2004年第2期47卷 203-215页

作者： ZHU Ziqiang FU hongyan liu Hang WANG Xiaolu Beijing University of Aeronautics and Astronautics Beijing 100083 China Beijing University of Aeronautics and Astronautics Beijing 100083 China Beijing University of Aeronautics and Astronautics Beijing 100083 China Beijing University of Aeronautics and Astronautics Beijing 100083 China

A simplified adaptive wing, which deflects its leading edge and trailing edge flaps to vary its shape, is calculated to investigate the potential aerodynamic gains and compared with a biobjective optimization (BO) wing in the present paper. In subsonic-transonic flights the deflection angle of a flap is determined through optimization using a deterministic method. In supersonic flight the flaps are not deflected due to the requirement of having a minimum drag. For comparison the aerodynamic characteristics of a BO airfoil and wing is calculated. A parallel genetic algorithm is used in BO. Euler equations served as governing equations in flow field calculation. Numerical results in both 2D (airfoil) and 3D (wing) cases show that aerodynamic performances of the two design airfoils and wings are much better than those of the original ones, with the adaptive design one the best. Keywords simplified adaptive wing - biobjective optimization - airfoil and wing design

关键词： simplified adaptive wing, biobjective optimization, airfoil and wing design.