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Plant Diversity 2021年第2期43卷 111-116页

作者： juan Yue Rong Li CAs Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of sciences Beijing100049China

The species composition of plant communities is determined by a number of factors,including current environmental conditions as well as biogeographical and evolutionary *** evidence that plant diversity decreases and species relatedness increases along latitudinal and environmental gradients(e.g.,low temperatures),it remains unclear whether these same patterns occur along elevational gradients,especially in the subtropical mountainous areas harboring rich *** this study,we explored the pattern of phylogenetic relatedness of woody angiosperm assemblages and examined the effects of temperature variables on the phylogenetic relatedness among angiosperm woody plants using generalized linear model in subtropical forest communities along a broad elevational gradient in the Dulong Valley of Yunnan Province,*** results showed that woody angiosperm species in local forest plots tend to be more phylogenetically related at higher elevations and in areas with lower ***,winter average temperature,rather than mean annual temperature,is a major predictor of the pattern of increasing phylogenetic relatedness with increasing *** finding is consistent with the prediction of‘Tropical Niche Conservatism’hypothesis,which highlights the role of niche constraints in driving phylogenetic community assembly along an elevational gradient.

关键词： Dulong Valley Ecological tolerance Habitat filtering Niche conservatis

Quality assessment of the Topo-Iberia CGPs stations and data quality's effects on postfit ionosphere-free phase residuals

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Geodesy and Geodynamics 2024年第2期15卷 189-199页

作者： juan A.García-Armenteros Center for Advanced studies in Earth sciences Energy and Environment(CEACTEMA)University of Jaén23071 JaenSpain

This paper analyzed GPs data from the Topo-Iberia network spanning almost 12 years(2008-2020).The data quality information for all 26 Topo-Iberia stations is provided for the first time,complementing the spanish Geological survey’s storage *** analyses based on quality indicators obtained using TEQC have been carried *** guidelines and data quality information from the IGs stations have been considered as the quality references,with the stations ALJI,EPCU,and TIOU standing out as the worst stations,while on the contrary,FUEN,PALM,PILA,and TRIA meet the quality requirements to become an IGs *** relationship between the GPs data quality and their GAMIT-and Gipsy X-derived postfit ionosphere-free phase residuals has also been investigated,and the results reveal an inversely proportional *** has been found that the stations showing an increase in elevation of the horizon line,also show an increase in cycle slips and multipath,are among the poorest quality stations,and among those with the highest postfit RMs of phase ***,the evolution of the vegetation around the antenna should be considered as it could cause a progressive loss of quality,which is not complying with the IGs *** quality assessment shows that the Topo-Iberia stations are appropriate for geodetic purposes,but permanent monitoring would be necessary to avoid the least possible loss of data and *** addition,a method to characterize the GNss data quality is proposed.

关键词： GPs dataquality's effects IGs quality standard Postfit LC phase residual Qualityassessment Topo-Iberia CGPs network

The Initial Mesoscale Vortexes Leading to the Formation of Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric sciences 2023年第5期40卷 804-823页

作者： shenglan WU juan FANG shanghai Central Meteorological Observatory CMAShanghai 200030China Key Laboratory of Mesoscale severe Weather(MOE) School of the Atmospheric SciencesNanjing University163 Xianlin RoadNanjing 210046China

A statistical analysis of the initial vortexes leading to tropical cyclone(TC)formation in the western North Pacific(WNP)is conducted with the ECMWF ERA5 reanalysis data from 1999 to *** is found that TCs in the WNP basically originate from three kinds of vortexes,i.e.,a mid-level vortex(MV),a low-level vortex(LV),and a relatively deep vortex with notable vorticity in both the lower and middle troposphere(DV).Among them,LV and DV account for 47.9%and 24.2%of tropical cyclogenesis events,respectively,while only 27.9%of TCs develop from the MV,which is much lower than that which occurs in the North Atlantic and eastern *** a difference might be ascribed to the active monsoon systems in the WNP all year *** to the nearly upright structure of mid-level convergence in the early pre-genesis stage,TC genesis efficiency is the highest in *** with MV,LV generally takes a shorter time to intensify to a TC because of the higher humidity and the stronger low-level cyclonic circulation,which is related to air-sea interaction and boundary-layer *** examination of the relationship between tropical cyclogenesis and large-scale flow patterns indicate that the TC genesis events associated with LV are primarily related to the monsoon shear line,monsoon confluence region,and monsoon gyre,while those associated with MV are frequently connected with easterly waves and wave energy dispersion of preexisting *** with other flow patterns,tropical cyclones usually form and intensify faster in the monsoon confluence region.

关键词： TC formation initial mesoscale vortexes TC genesis efficiency large-scale flow patterns

Photosynthetic and Molecular Markers of CO_2-mediated Photosynthetic Downregulation in Nodulated Alfalfa

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Journal of Integrative Plant Biology 2013年第8期55卷 721-734页

作者： Alvaro sanz-sez Gorka Erice Iker Aranjuelo Ricardo Aroca juan Manuel Ruíz-Lozano Jone Aguirreolea juan Jos Irigoyen Manuel sanchez-Diaz Department of Plant Biology University of NavarraPamplonaE-31008Spain Department of Plant Biology University of BarcelonaBarcelonaE-8028Spain Department of Plant Biology University of Illinois at Urbana-Champaign61801USA Agrobiotechnology Institute Public University of NavarraMutilva BajaE-31192Spain Department of soil Microbiology and symbiotic systems Zaidin Experimental Station(CSIC)GranadaE-18008.Spain

Elevated CO2 leads to a decrease in potential net photosynthesis in long-term experiments and thus to a reduction in potential growth. This process is known as photosynthetic downregulation. There is no agreement on the definition of which parameters are the most sensitive for detecting CO2 acclimation. In order to investigate the most sensitive photosynthetic and molecular markers of CO2 acclimation, the effects of elevated CO2, and associated elevated temperature were analyzed in alfalfa plants inoculated with different sinorhizobium meliloti strains. Plants （Medicago sativa L. cv. Aragon） were grown in summer or autumn in temperature gradient greenhouses （TGG）. At the end of the experiment, all plants showed acclimation in both seasons, especially under elevated summer temperatures. This was probably due to the lower nitrogen （N） availability caused by decreased N2-fixation under higher temperatures. Photosynthesis measured at growth CO2 concentration, rubisco in vitro activity and maximum rate of carboxylation were the most sensitive parameters for detecting downregulation. severe acclimation was also related with decreases in leaf nitrogen content associated with declines in rubisco content （large and small subunits） and activity that resulted in a drop in photosynthesis. Despite the sensitivity of rubisco content as a marker of acclimation, it was not coordinated with gene expression, possibly due to a lag between gene transcription and protein translation.

关键词： Carbon dioxide Medicago sativa (alfalfa) photosynthetic downregulation RbcL and Rbcs sinorhizobium meliloti.

Reflected sPDEs Driven by Fractional Noises

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Acta Mathematicae Applicatae sinica 2020年第2期36卷 347-360页

作者： juan YANG Qing ZHOU school of science Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,we study the stochastic partial differential equation with two reflecting smooth walls h^1 and h^2,driven by a fractional noise,which is fractional in time and white in *** large deviation principle for the law of the solution to this equation,will be established through developing a classical ***,we obtain the H?lder continuity of the solution.

关键词： stochastic partial differential equations with two reflecting walls fractional Brownian motion large deviation principle Holder continuity

Kinetic study on desulfurization and denitrification using microwave irradiation over activated carbon

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science China(Technological sciences) 2011年第9期54卷 2321-2326页

作者： MA shuangChen YAO juan juan JIN Xin ZHANG Bo school of Environment North China Electric Power University Baoding 071003 China

sulfur dioxide （sO2） and nitrogen oxide （NOx） in flue gas can be removed by combining microwave induced catalysis and adsorption on activated carbon. The reaction mechanisms of desulfurization and denitrification by microwave irradiation were analyzed based on the measurement of reaction products. Thermodynamic parameters for desulfurization and denitrification by thermal-carbon reduction were predicted according to the principles of thermodynamics. The experimental results indicated that the desulfurization and denitrification reaction processes include three reaction stages： slow reaction zone, transitional zone and rapid reaction zone. In high temperature zone, activation energies for the reduction of sO2 and nitrogen monoxide （NO） are 30.69 and 24.06 kJ mo1-1, respectively. This study shows that microwave can effectively enhance the removal of pollutants through its heating effect and the induced catalysis.

关键词： microwave desulfurization denitrification kinetics

Two 8-node quadrilateral spline elements by B-net method

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Acta Mechanica sinica 2012年第6期28卷 1620-1629页

作者： juan Chen Chong-Jun Li school of Mathematics and Quantitative Economics Dongbei University of Finance and Economics school of Mathematical sciences Dalian University of Technology

Isoparametric quadrilateral elements are widely used in the finite element method, but the accuracy of the isoparametric quadrilateral elements will drop obviously deteriorate due to mesh distortions. spline functions have some properties of simplicity and conformality. Two 8-node quadrilateral elements have been developed using the trian- gular area coordinates and the B-net method, which can ex- actly model the quadratic field for both convex and concave quadrangles. some appropriate examples are employed to evaluate the performance of the proposed elements. The nu- merical results show that the two spline elements can obtain solutions which are highly accurate and insensitive to mesh distortions.

关键词： spline finite element B-net method Quadri-lateral element - Bivariate spline interpolation The secondorder completeness

software Vulnerabilities Overview:A Descriptive study

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Tsinghua science and Technology 2020年第2期25卷 270-280页

作者： Mario Calín sánchez juan Manuel Carrillo de Gea José Luis Fernández-Alemán Jesús Garcerán Ambrosio Toval the Department of Informatics and systems Faculty of Computer ScienceUniversity of Murcia

Computer security is a matter of great *** the last decade there have been numerous cases of cybercrime based on the exploitation of software *** fact has generated a great social concern and a greater importance of computer security as a *** this work,the most important vulnerabilities of recent years are identified,classified,and categorized individually.A measure of the impact of each vulnerability is used to carry out this classification,considering the number of products affected by each vulnerability,as well as its *** addition,the categories of vulnerabilities that have the greatest presence are *** on the results obtained in this study,we can understand the consequences of the most common vulnerabilities,which software products are affected,how to counteract these vulnerabilities,and what their current trend is.

关键词： descriptive study software security software vulnerabilities vulnerability databases

Fuzzy PID Control of space Manipulator for Both Ground Alignment and space Applications

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International Journal of Automation and computing 2014年第4期11卷 353-360页

作者： Fu-Cai Liu Li-Huan Liang juan-juan Gao Key Lab of Industrial Computer Control of Hebei Province Yanshan University

Considering gravity change from ground alignment to space applications, a fuzzy proportional-integral-differential(PID)control strategy is proposed to make the space manipulator track the desired trajectories in different gravity environments. The fuzzy PID controller is developed by combining the fuzzy approach with the PID control method, and the parameters of the PID controller can be adjusted on line based on the ability of the fuzzy controller. simulations using the dynamic model of the space manipulator have shown the effectiveness of the algorithm in the trajectory tracking problem. Compared with the results of conventional PID control,the control performance of the fuzzy PID is more effective for manipulator trajectory control.

关键词： space manipulator trajectory tracking ground alignment space applications fuzzy proportional-integral-differential (PID) gravity environment