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Bibliometric evaluation of the status of Picea research and research hotspots:comparison of China to other countries

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Journal of Forestry Research 2020年第4期31卷 1103-1114页

作者： Guozhen Duan Yu'e bai Dongmei Ye Tao Lin peng peng Min Liu Shulan bai College of Forestry Inner Mongolia Agricultural University275 Xueyuan StreetHohhot 010019People’s Republic of China

Picea *** are important components of boreal and subalpine *** have a wide geographical range in the Northern Hemisphere,extending from the Eurasian continent to North *** this study,publications on Picea species from 2002 to 2016 were identified via the Web of Science(WoS)and the China National Knowledge Infrastructure(CNKI)databases,and subjected to relationship network visualization using CiteSpace *** study represents the first such analysis of Picea and provides a reference for bibliometrics in forest tree species *** results show that the total number of publications on Picea archived in WoS was20,958 and that the number of papers published annually has increased over time,peaking at 1725 in *** studies were mainly conducted in North America,Europe and Asia;among them,Canada published the most papers and showed the strongest betweenness centrality(0.11).Among research institutions,the Swedish University of Agricultural Sciences in Uppsala had the highest publication *** research contributions of the Chinese Academy of Sciences,the Chinese Academy of Forestry,and Beijing Forestry University have improved rapidly in recent years,greatly enhancing the international impact of Chinese research in this *** research contents were grouped into five categories:forest ecosystems,pest resistance,extraction and functional analyses of active ingredients from various plant organs,nursery and afforestation techniques,and timber quality *** China,the number of papers from the CNKI database was4532,increasing at an even *** research topics on Picea included forest ecosystems,seedling and afforestation techniques,basic studies on individual species and populations,and pests and *** and outside China,hotspots in Picea research included the relationships between Picea and environmental factors,and the genomic sequences of Picea.

关键词： Picea Bibliometrics Hotspots Web of science Chinese National Knowledge Infrastructure

On the Existence and Uniqueness of Solutions to Stochastic Differential Equations Driven by G-Brownian Motion with Integral-Lipschitz Coefficients

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 589-610页

作者： Xue-peng bai Yi-qing LIN Institut de Recherche Mathématique de Rennes Université de Rennes1 School of Mathematics Shandong University Institut de Recherche Mathématique de Rennes Université de Rennes

In this paper, we study the existence and uniqueness of solutions to stochastic differential equations driven by G-Brownian motion （GSDEs） with integral-Lipschitz coefficients.

关键词： G-Brownian motion G-expectation G-stochastic differential equations G-backward stochastic differential equations integral-Lipschitz condition

Dynamics and pattern formation in a modified Leslie-Gower model with Allee effect and Bazykin functional response

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International Journal of Biomathematics 2017年第5期10卷 301-326页

作者： peng feng Department of Mathematics Florida Gulf Coast University 11501 FGCU Blvd. S. Fort Myers FL 33965 US

In this paper, we study the dynamics of a diffusive modified Leslie-Cower model with the multiplicative Allee effect and Ba^zykin functional response. We give detailed study on the stability of equilibria. Non-existence of non-constant positive steady state solutions are shown to identify the rage of parameters of spatial pattern formation. We also give the conditions of Turing instability and perform a series of numerical simulations and find that the model exhibits complex patterns.

关键词： Predator-prey Leslie-Gower Bazykin functional response Turing instability pattern formation global stability.

Effect of cooling temperature on the microstructure and corrosion behavior of X80 pipeline steel

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 347-353页

作者： Jing Ma Fan feng bai-qing Yu Hai-feng Chen Li-feng Fan School of Materials Hebei University of Science and TechnologyShijiazhuang 050018China Hebei Key Laboratory of Material Near-Net Forming Technology Shijiazhuang 050018China School of Transportation Inner Mongolia UniversityHohhot 010070China

Dual-phase accelerated cooling(DPAC) was applied to X80 pipeline steel to obtain its microstructure with different amounts of bainite and ferrite. The microstructure, hardness, and polarization behaviors of the steel, cooled to different temperatures, were investigated. Results showed that, with decreasing cooling temperature, the amount of polygon ferrite(PF) increased while that of acicular ferrite(AF) decreased. The amount of bainite correspondingly decreased, except when cooled to 760°C. Moreover, the grain size of ferrite increased. The corrosion behaviors of different phases were distinct. Martensite/austenite(M/A) islands presented at the grain boundary of the PF phase caused small pits. Numerous micro-corrosion cells were formed in the AF and bainite phases, where micropores were prone to form. X80 pipeline steel cooled to 700°C had the best corrosion resistance in the simulated seawater. The decreased amount of the PF phase reduced the area of cathode, resulting in slight corrosion. About 40 vol% of the bainite phase provided strength while the PF phase provided adequate ductility to the X80 steel. It was concluded that the appropriate cooling temperature was 700°C for ideal corrosion resistance and mechanical properties.

关键词： X80 pipeline steel Dual-phase accelerated cooling microstructure corrosion behavior

A Novel Coumarin-based Fluorescence Chemosensor for Fe^3＋

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Chemical Research in Chinese Universities 2014年第4期30卷 560-565页

作者： WANG Ruiping WAN Qihua feng feng bai Yunfeng Department of Chemistry College of Sciences Nanchang University Nanchang 330047 P. R. China Department of Chemistry Datong University Datong 037009 P. R. China

A novel coumarin derivative[7-diethylamino-2-oxo-2H-chromene-3-carboxylic acid（6-amino-pyridin2-yl）-amide,CFe1] has been synthesized and its potential application as a chemosensor for the detection of metal ions has been further *** responses of CFe1 to Fe^3＋ were studied by fluorescence emission spectrometry in the presence of other metal ions such as Al^3＋,Ba^2＋,Ca^2＋,Co^3＋,Cr^3＋,Cu^2＋,Fe^2＋,Hg^2＋,Mg^2＋,Mn^2＋,Na^＋,Ni^＋,Pb^2＋,Zn^2＋,K^＋,and Ag^＋.CFe1 showed a good selectivity for Fe^3＋ with fast response,a wide pH span of 3.3-9.18,and a large Stocks ***1 in the presence of Fe^3＋ and ethylene diamine tetraacetic acid（EDTA） makes the blue solution fade to colorless,which is due to the formation of CFe1-Fe^3＋ complex instead of any catalytic action of Fe^3＋.Furthermore,the imaging of Fe^3＋ in cultured single mice microglia cells was realized with the aid of CFe1,indicating that CFe1 has a great potential to be used as promising models for the future design of novel and robust chemosensor for metal ion detection in the field of biomedical and environmental analyses.

关键词： Coumarin Fe3+ Fluorescence Selectivity

A Control Algorithm for the Optimization of Batch Reactor-Based Processes

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Fluid Dynamics & Materials Processing 2019年第4期15卷 307-319页

作者： Yanling bai feng Liu Artificial Intelligence Institute Zhengzhou Railway Vocational&Technical CollegeZhengzhouChina Cyber Security Guard Henan Provincial Public Security DepartmentZhengzhouChina

Levenberg-Marquardt(LM)algorithm is applied for the optimization of the heat transfer of a batch *** validity of the approach is verified through comparison with experimental *** is found that the mathematical model can properly describe the heat transfer relationships characterizing the considered system,with the error being kept within±2℃.Indeed,the difference between the actual measured values and the model calculated value curve is within±1.5℃,which is in agreement with the model assumptions and demonstrates the reliability and effectiveness of the algorithm applied to the batch reactor heat transfer ***,the present work provides a theoretical reference for the conversion of practical problems in the field of chemical production into mathematical models.

关键词： Batch reactor LM algorithm parameter estimation model

Contribution of diffusion,perfusion and functional MRI to the disconnection hypothesis in subcortical vascular cognitive impairment

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Stroke & Vascular Neurology 2018年第3期3卷 131-139页

作者： Qing Ye feng bai Department of Neurology Affiliated Drum Tower HospitalNanjing University Medical SchoolNanjingJiangsuChina Jiangsu Province Stroke Center for Diagnosis and Therapy NanjingChina Nanjing Neuropsychiatry Clinic Medical Center NanjingChina Jiangsu Key Laboratory for Molecular Medicine Nanjing University Medical SchoolNanjingChina

Vascular cognitive impairment(VCI)describes all forms of cognitive impairment caused by any type of cerebrovascular *** identification of VCI is quite difficult due to the lack of both sensitive and specific *** damage to the white matter tracts,which connect the cortical and subcortical regions,has been shown in subcortical VCI(SVCI),the most common subtype of VCI that is caused by small vessel *** specific MRI sequences,including diffusion tensor imaging(DTI)and functional MRI(fMRI),have emerged as useful tools for identifying subtle white matter changes and the intrinsic connectivity between distinct cortical *** review describes the advantages of these two modalities in SVCI research and the current DTI and fMRI findings on *** DTI technique,a variety of studies found that white matter microstructural damages in the anterior and superior areas are more specific to ***,functional brain abnormalities detected by fMRI have also been mainly shown in anterior brain areas in *** characteristic distribution of brain abnormalities in SVCI interrupts the prefrontal-subcortical loop that results in cognitive impairments in particular domains,which further confirms the‘disconnection syndrome’*** addition,another MRI technique,arterial spin labelling(ASL),has been used to describe the disconnection patterns in a variety of conditions by measuring cerebral blood *** role of the ASL technique in SVCI research is also ***,the review proposes the application of multimodality fusion in the investigation of SVCI pathogenesis.

关键词： impairment subcortical diffusion

A hybrid multidimensional Riemann solver to couple self-similar method with MULTV method for complex flows

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Chinese Journal of Aeronautics 2021年第7期34卷 29-38页

作者： feng QU Di SUN Junjie FU Junqiang bai School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

Since proposed,the self-similarity variables based genuinely multidimensional Riemann solver is attracting more attentions due to its high resolution in multidimensional complex ***,it needs numerous logical operations in supersonic cases,which limit the method’s applicability in engineering problems *** order to overcome this defect,a hybrid multidimensional Riemann solver,called HMTHS(Hybrid of MulTv and multidimensional HLL scheme based on Self-similar structures),is *** simulates the strongly interacting zone by adopting the MHLLES(Multidimensional Harten-Lax-van Leer-Eifeldt scheme based on Self-similar structures)scheme at subsonic speeds,which is with a high resolution by considering the second moment in the similarity ***,it adopts the MULTV(Multidimensional Toro and Vasquez)scheme,which is with a high resolution in capturing discontinuities,to simulate the flux at supersonic *** numerical experiments,including both one-dimensional cases and twodimensional cases,are ***-dimensional moving contact discontinuity case and sod shock tube case suggest that HMTHS can accurately capture one-dimensional expansion waves,shock waves,and linear contact ***-dimensional cases,such as the double Mach reflection case,the supersonic shock/boundary layer interaction case,the hypersonic flow over the cylinder case,and the hypersonic viscous flow over the double-ellipsoid case,indicate that the HMTHS scheme is with a high resolution in simulating multidimensional complex ***,it is promising to be widely applied in both scholar and engineering areas.

关键词： Complex flows Computational fluid dynamics Multidimensional Riemann solver Self-similar

Digital ridgelet reconstruction based on local dual frame

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Science in China(Series F) 2005年第6期48卷 782-794页

作者： bai Jian feng Xiangchu Department of Applied Mathematics Xidian University Xi'an 710071 China

A global dual frame （GDF） representation for the digital ridgelet reconstruction algorithm is discussed and a novel concept of local dual frame （LDF） is presented. Based on the properties of LDF, we propose a new digital ridgelet reconstruction algorithm. The method reduces the redundancy in the digital ridgelet reconstruction while keeping the characteristics of low computation cost. When applying it to the image compression and denoising, good results are obtained.

关键词： ridgelet fast Slant Stack digital ridgelet global dual frame local dual frame