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Human Settlement Evaluation in Mountain Areas Based on Remote Sensing,GIS and Ecological Niche Modeling

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Journal of Mountain Science 2013年第3期10卷 378-387页

作者： zhao jian XU Min lu Shi-lei CAO Chun-xiang State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Graduate School of Chinese Academy of Sciences

The Qinghai-Tibet Plateau is the word＇s highest and largest plateau. Due to increasing demands for environment exploration and tourism, a large transitional area is required for altitude adaptation. Hehuang valley, which locates in the transition zone between the Loess Plateau and the Qinghai-Tibet Plateau, has convenient transportation and relatively low elevation. Our question is whether the geographic conditions here are appropriate for adapted stay before going into the Qinghai-Tibet Plateau. Therefore, in this study, we examined the potential use of ecological niche modeling （ENM） for mapping current and potential distribution patterns of human settlements. We chose the Maximum Entropy Method （Maxent）, an ENM which integrates climate, remote sensing and geographical data, to model distributions and assess land suitability for transition areas. After preprocessing and selection, the correlation between variables and spatial auto- correlation input data were removed and 106 occurrence points and 9 environmental layers were determined as the model inputs. The threshold- independent model performance was reasonable according to lO times model running, with the area under the curve （AUC） values being 0.917± 0.01, and 0.923±0.002 for test data. Cohen＇s kappa coefficient of model performance was 0.848. Results showed that 82.22% of the study extent was not suitable for human settlement. Of the remaining areas, highly suitable areas aceounted for 1.19%, moderately for 5.3% and marginally for 11.28%. These suitable areas totaled 418.79 km2, and 86.25% of the sample data was identified in the different gradient of suitable *** decisive environmental factors were slope and two climate variables： mean diurnal temperature range and temperature seasonality. Our model showed a good performance in mapping and assessing human settlements. This study provides the first predicted potential habitat distribution map for human settlement in Ledu County, which could also help in

关键词： Human settlement Remote sensing Suitability assessment Ecological niche modeling

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU jian-Qiang MA zhao-Peng CHENG Si LIU Zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Microstructure and microhardness of directionally solidified NiAl-W eutectic alloy

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Rare Metals 2020年第10期39卷 1174-1180页

作者： jian-Jun Gao Zhi-Long zhao lu-Feng Wei Kai Cui Lin Liu School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

The microstructure and microhardness of directionally solidified NiAl-W eutectic alloys at growth rates of 2-25μm·s^-1 were investigated by a Bridgman crystal growing facility at a temperature gradient of 300 K·cm^-*** view of the competitive growth between W dendritic and eutectic phases,W dendritic phase was eliminated,whereas the fully eutectic phase was prominent in the steady progress of the directionally solidified NiAl-W eutectic *** the growth rate(V)increased,both the structure and solid/liquid interface of the directionally solidified NiAl-W eutectic alloys changed from planar to *** the fibrous spacing(d)and the diameter(a)decreased with increase in growth rate(V).The Vickers microhardness(H)of the directionally solidified NiAl-W eutectic alloys decreased with fibrous spacing(d)or diameter(a)*** relationships of H to d and a were H=371.58 d^(-0.09)and H=297.70 a^(-0.09),respectively.

关键词： Microstructure Directional solidification Eutectic alloy Microhardness

Prussian Blue/Cellulose Acetate Thin Film Composite Nanofiltration Membrane for Molecular Sieving and Catalytic Fouling Resistance

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Chinese Journal of Polymer Science 2023年第4期41卷 593-604,I0009页

作者： Hai-Bo Lin jian-Guo zhao Na lu Qiu Han jian-Qiang Wang jian-Min Guan Xiao Wang Fu Liu Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China Qinghai University Qinghai810016China University of Chinese Academy of Sciences Beijing100049China

Nanofiltration(NF)membranes as high selective separators are appealing for molecular sieving,which still remains a great challenge for the mixed dyes with same *** this study,cellulose acetate(CA)membranes were firstly aminated by ethylene imine polymer(PEI),and then the thin film of metal organic frameworks(MOFs)were constructed onto aminated CA membrane through forward-diffusion,slow crystallization and in situ growth of Fe Co-Prussian blue(FeCo-PB)crystallization *** designed PB@CA composite NF membrane shows an ideal rejection for Congo red(CR)/methyl orange(MO)mixture solution,with 99.7%±0.2%for CR and 33.5%±2%for *** addition,the composite NF membrane demonstrated good efficiency for photocatalytic degradation of organic fouling(permeability recovery ratio was up to 92%)due to the active FeCo-PB ***,this work provides a practical strategy to prepare MOFs mediated thin film composite nanofiltration membrane for precise molecular sieving and catalytic antifouling performances.

关键词： Nanofiltration membrane Molecular sieving Catalytic fouling resistance Prussian blue

A Control Method for Congested Traffic in the Car-Following Model

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Chinese Physics Letters 2012年第5期29卷 49-51页

作者： GE Hong-Xia YU jian lu zhao-Ming Faculty of Science Ningbo UniversityNingbo 315211 Department of Civil and Architectural Engineering City University of Hong KongKowloonHong Kong

A simple control method to suppress traffic congestion is proposed for the car-following *** stability conditions are derived by using the control method,and the feedback signals,which act on our traffic system,are extended to the car-following *** control signals will play an effect only if the traffic is *** corresponding numerical simulation results agree well with our theoretical analysis,and our control method can successfully suppress traffic jams.

关键词： traffic method stability

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国外罕见病管理制度对中国的启示

基础医学与临床 2017年第2期37卷 273-276页

作者：王煜卢建华赵太宏肖雨龙南京医科大学附属南京医院(南京市第一医院)医务处江苏南京210006 南京医科大学医政学院江苏南京210029

通过对部分国家和地区罕见病法案的分析,探讨罕见病管理的国际经验。中国应尽快推进罕见病立法,明确罕见病界定标准,加强转化医学研究,提高罕见病诊断治疗水平。应加强政策导向作用,完善激励措施,加强多部门协作,建立健全罕见病医疗保... 详细信息

通过对部分国家和地区罕见病法案的分析,探讨罕见病管理的国际经验。中国应尽快推进罕见病立法,明确罕见病界定标准,加强转化医学研究,提高罕见病诊断治疗水平。应加强政策导向作用,完善激励措施,加强多部门协作,建立健全罕见病医疗保障体系,建立与中国国情相适应的罕见病管理体系。

关键词：罕见病罕用药立法界定标准

Nonexistence of maximizers for the functional of the centroaffine Minkowski problem

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Science China Mathematics 2018年第3期61卷 511-516页

作者： jian lu Department of Applied Mathematics Zhejiang University of Technology

The centroafhine Minkowski problem is studied, which is the critical case of the L_p-Minkowski problem. It admits a variational structure that plays an important role in studying the existence of *** this paper, we fi... 详细信息

关键词： centroaffine Minkowski problem Monge-Ampere equation variational structure Blaschke-Santalo inequality

Anisotropic inverse harmonic mean curvature flow

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Frontiers of Mathematics in China 2014年第3期9卷 509-521页

作者： jian lu Department of Applied Mathematics Zhejiang University of Technology Hangzhou 310032China

We study the evolution of convex hypersurfaces H（., t） with initial H（., 0） = 0H0 at a rate equal to H - f along its outer normal, where H is the inverse of harmonic mean curvature of H（., t）, H0 is a smooth, closed, and uniformly convex hypersurface. We find a θ^＊〉 0 and a sufficient condition about the anisotropic function f, such that if θ 〉 θ^＊, then H（.,t） remains uniformly convex and expands to infinity as t →∞ and its scaling, H（-, t）e^-nt, converges to a sphere. In addition, the convergence result is generalized to the fully nonlinear case in which the evolution rate is log H - log f instead of H - f.

关键词： Curvature flow parabolic equation asymptotic behavior

Dual-level stress plateaus in honeycombs subjected to impact loading:perspectives from bucklewaves, buckling and cell-wall progressive folding

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Acta Mechanica Sinica 2019年第1期35卷 70-77,I0003页

作者： Lang Li Zhenyu zhao Rui Zhang Bin Han Qiantheng Zhang Tian jian lu State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong UniversityXi'an 710049China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China MOE Key Laboratory for Multifunctional Materials and Structures Xi'an Jiaotong UniversityXi'an 710049China School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049China School of Engineering Brown UniversityProvidenceRI 02912USA Research Institute of Xi'an Jiaotong University ZhejiangHangzhou 311215China

Dual-level stress plateaus (i.e., relatively short peak stress plateaus, followed by prolonged crushing stress plateaus) in metallic hexagonal honeycombs subjected to out-of-plane impact loading are characterized using a combined numerical and analytical study, with the influence of the strain-rate sensitivity of the honeycomb pare nt material accounted for. The predicti ons are validated against existing experimental measurements, and good agreement is achieved. It is demonstrated that honeycombs exhibit dual-level stress plateaus when bucklewaves are initiated and propagate in cell walls, followed by buckling and progressive folding of the cell walls. The abrupt stress drop from peak to crushing plateau in the compressive stress versus strain curve can be explained in a way similar to the quasi-static buckling of a clamped plate. The duration of the peak stress plateau is more evident for strain-rate insensitive honeycombs.

关键词： Honeycomb Impact loading Dual-level stress Strain-rate sensitivity