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Plastid phylogenomics provides new insights into the systematics,diversification,and biogeography of Cymbidium(Orchidaceae)

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Plant Diversity 2024年第4期46卷 448-461页

作者： Hai-Yao Chen Zhi-Rong Zhang Xin Yao ji-Dong Ya Xiao-Hua jin {2.n Wang Lu Lu De-Zhu {2. Jun-Bo Yang Wen-bin Yu Center for Integrative Conservation&Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China university of Chinese Academy of sciences Huairou DistrictBeijing 101408China Plant Germplasm and Genomics Center Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China State Key Laboratory of Plant Diversity and Specility Crops Institute of BotanyChinese Academy of SciencesHaidian DistrictBeijing 100093China School of Pharmaceutical sciences Yunnan Key Laboratory of Pharmacology for Natural Productsand Yunnan College of Modern Biomedical IndustryKunming Medical UniversityKunmingYunnan 650500China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw 05282Myanmar

Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the ***,phylogenetic relationships of Cymbidium have not been well resolved,hampering investigations of species diversification and the biogeographical history of this *** this study,we construct a plastome phylogeny of 56 Cymbidium species,with four well-resolved major clades,which provides a framework for biogeographical and diversification rate *** dating and biogeographical analyses show that Cymbidium likely originated in the region spanning northern IndoBurma to the eastern Himalayas during the early Miocene(~2..10 Ma).It then rapidly diversified into four major clades in East Asia within approximately a million years during the middle *** *** to the adjacent regions(Borneo,Philippines,and Sulawesi)primarily occurred during the Pliocene-Pleistocene *** analyses indicate that the net diversification rate of Cymbidium has decreased since its origin,and is positively associated with changes in temperature and monsoon *** hydrothermal conditions brought by monsoon intensification in the early Miocene possibly contributed to the initial rapid diversification,after which the net diversification rate was reduced with the cooling climate after the middle *** transition from epiphytic to terrestrial habits may have enabled adaptation to cooler environments and colonization of northern niches,yet without a significant effect on diversification *** study provides new insights into how monsoon activity and temperature changes affected the diversification dynamics of plants in Southeast Asia.

关键词： Cymbidium East Asia Asian monsoons Climate change Biogeographical patterns

The change of Morin transition temperature in nanocrystalline α-Fe_2._3

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Chinese science Bulletin 1997年第4期42卷 344-346页

作者： li Haibo, GONG jie, ZHENG Weitao, CHEN Gang and YU Ruihuang1. {2. of Materials science, jilin university, Changchun 13002., china 2.{2. of Physics, Siping normal ( lege, Siping 136000, china department of Materials science Jilin University Changchun China department of Physics Siping Normal College Siping China

THE magnetic property of the ultrafine particles differs from that ot the bulk materials and has a lot of applications. Because of the size effect, magnetically ordered materials exhibit both superparamagnetism and collective magnetic excitation, and the magnetic transition temperature changes in the ultrafine particles with respect to the bulk materials as well. Bulk α-Fe2./sub>O3 is weakly ferromagnetic above the Morin transition temperature TM

关键词： Morin transition ultrafine particles Mossbauer effect.

A Perfect Representation of the limit on Solutions of a Difference Equation

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昆明理工大学学报(自然科学版) 1998年第2期 156-160+164页

作者： Cui Hongzhi (department of Mathematics Yunnan,Polytechnic university,{2. 650051) li Cunfu (Depatment of Basic sciences,{2. university of science and technology,{2. 650093)

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关键词： difference equation solution integer sequence convergence

Pointwise estimates for the maximal multilinear singular integral operators

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science china Mathematics 2005年第12期48卷 1696-1706页

作者： HU Guo’en, li Dengfeng & LU Shanzhen department of Applied Mathematics, university of Information Engineering, P. O. Box 1001 -747, Zhengzhou 450002. china College of Mathematical and Information sciences, Henan university, Kaifeng 475001, china department of Mathematics, Beijing normal university, Beijing 100875, china 1. department of Applied Mathematics University of Information Engineering P.O.Box 1001-747 450002 Zhengzhou China 2. College of Mathematical and Information sciences Henan University 475001 Kaifeng China 3. department of Mathematics Beijing Normal University 100875 Beijing China

Two pointwise estimates relating the maximal multilinear singular integral operators and some classical maximal operators are established. These pointwise estimates imply the rearrangement estimate and the BLO(Rn) est... 详细信息

关键词： multilinear singular integral,maximal operator,BMO (Rn),BLO (Rn).

Estimating surface evapotranspiration using combined MODIS and CBERS-02.data

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science china(Technological sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2. liU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, li Xiaowen1,2. ZHENG Hongsheng4 & CHEN jiayi4 1. State Key Laboratory of Remote Sensing science, Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 100101, china 2. Research Center for Remote Sensing and GIS, department of Geography, Beijing normal {12., Beijing 100875, china 3. Graduate {12. of Chinese Academy of sciences, Beijing 100039, china 4. department of Atmospheric Physics, Peking {12., Beijing 100871, china 1. State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02.data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2.04. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Analytical Potential Energy Function,Spectroscopic Constants and Vibrational Levels for A^1E_u^+ State of Dimer ~7li_2

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Communications in Theoretical Physics 2007年第12期48卷 1081-1087页

作者： SHI De-Heng~1 MA Heng~1 SUN jin-Feng~(1,2.and ZHU Zun-Lue~1~1 College of Physics & Information Engineering,Henan normal {2.,Xinxiang 453007,china~2.department of Physics & Electron science,Luoyang normal {2.,Luoyang 47102.,china College of Physics & Information Engineering Henan Normal University Xinxiang 453007 China department of Physics & Electron science Luoyang Normal University Luoyang 471022 China

The symmetry-adapted-duster configuration-interaction method is used to investigate the spectroscopicproperties of ~7li_2.A^1∑_u^+) over the internuclear distance ranging from 2.4ao to *** complete potential energycurves are calculated at numbers of basis *** the ab initio calculated points are fitted to the analytic MurrellSorbie function and then employed to compute the spectroscopic *** comparison,the spectroscopic constantsreproduced by the potential attained at D95(3df,3pd) are found to be very close to the experiments,a^d the values (T_e,D_e,R_e,ω_e,ω_eχ_e,α_e and B_e) are of 1.732.93 eV,1.161 36 eV,0.313 2. nm,2.1.95 cm^(-1),1.62. cm^(-1),0.005 35 cm^(-1),and0.490 cm^(-1),*** the potential obtained at D95(3df,3pd),the totally 75 vibrational states are found whenJ=*** vibrational levels,the classical turning points and the inertial rotation constants of the first 68 vibrationalstates are calculated for the first time and compared with the available *** agreement is *** centrifugal distortion constants of the first 32.vibrational states are also reported for the first *** reasonabledissociation limit for ~7li_2.A^1∑_u^+) is deduced using the calculated results at present.

关键词： analytic potential energy function harmonic frequency dissociation energy vibrational level classical turning point

NOTE ON REGULAR D-OPTIMAL MATRICES

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Chinese Annals of Mathematics,Series B 2003年第2期24卷 215-220页

作者： li QIAOliANG {2. of Mathematics, Hunan normal university, Changsha 410081, china. Center for Combinatorics, Nankai university, Tianjin 300071, china. E-mail: liqiaoliang@*** Hunan normal Univ Dept Math Changsha 410081 Peoples R China Nankai Univ Ctr Combinator Tianjin 300071 Peoples R China

Let A be a j x d (0,1) matrix. It is known that if j = 2. - 1 is odd, then det(AAT) ≤ (j+1)((j+1)d/4j)j; if j is even, then det(AAT) ≤ (j+1)((j+2.d/4(j+1))j. A is called a regular D-optimal matrix if it satisfies the equality of the above bounds. In this note, it is proved that if j = 2. - 1 is odd, then A is a regular D-optimal matrix if and only if A is the adjacent matrix of a (2. - 1, k, (j + l)d/4j)-BIBD; if j = 2. is even, then A is a regular D-optimal matrix if and only if A can be obtained from the adjacent matrix B of a (2. + 1,k + 1,(j + 2.d/4(j +1))-BIBD by deleting any one row from B. Three 2. x 42.regular D-optimal matrices, which were unknown in [11], are also provided.

关键词： Regular .D-optimal matrices Simplex Weighing design

Uncountable　Infinity　of　Periodic　Solutions　of　Some　Nonlinear　Autonomous　Differential－Difference　Equations

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昆明理工大学学报(自然科学版) 1995年第2期 1-11页

作者： li ji{2. Zhao Xiaohua lin Yiping (1)department of Basic science,kunming Institute of technology, kunming 650093 2.Yunnan university,kunming 65009 1)

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关键词： Periodic solutions Generalized Hamiltonian systems Differential difference equations.

SIMULATION OF NON-POINT POLLUTANTS EVOLUTION IN COASTAL PLAIN ISLAND-A CASE STUDY OF CHONGMING ISLAND

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Journal of Hydrodynamics 2008年第2期20卷 246-253页

作者： YIN Hai-long jiANG Wen-yan li jian-hua College of Environmental science and Engineering Tongji University Shanghai 200092 China department of Environmental science East China Normal University Shanghai 200063 China

The coastal plain region usually shows the agricultural dominated industry mode, so more and more attention is paid to non-point pollutants discharge. In this study, the method for assessing the influence of non-point pollutants discharge on river water quality is probed which is concluded as follows：（1） Considering the costal plain island is characterized as nearly even elevation, the conventional gravitational runoff confluence method based on eight-point gravitational flowing directions （DS） is unable to compute the runoff confluence received by the surrounding rivers, so a new method of triangular confluence based on three-points of grid center and the river segments is presented. Further the equations of non-point pollutants loads estimation and non-point pollutants confluence on rivers are presented. （2. The integration mode of non-point pollutants model and river water quality model is presented so as to further assess the non-point pollutants contribution to river water quality. （3） With the Chongming Island, the third largest island in china, as an example, the above-mentioned equations are specified. For this island, the non-point pollutants loads are estimated and linked to the developed water quality model of the river network in the island, and further the non-point pollution evolution in river network is simulated. In this scenario, the non-point pollution contribution to river water quality over the whole island is clearly displayed, and the area where the river water quality is seriously influenced by non-point pollutants discharge is distinctly depicted. This scenario also shows the water quality contribution ratio of non-point pollution to point pollution can be in the range of 55.5% to 44.5% which proves the importance of non-point pollution control in costal plain islands.

关键词： non-point pollution runoffconfluence water quality model Chongming Island