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A taxonomic re-assessment in the Chinese Bupleurum(Apiaceae):Insights from morphology,nuclear ribosomal internal transcribed spacer,and chloroplast(trnH-psbA,matK) sequences

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Journal of Systematics and Evolution 2011年第6期49卷 558-589页

作者： Chang-Bao WANG Xiang-Guang MA Xing-Jin HE(college of Life Science,sichuan university,chengdu 610064.{4.) (college of Life Science Sichuan University Chengdu 610064 China)

As one of the big genera in Apiaceae,Bupleurum *** received considerable attention from plant ***,there are still many gaps in our knowledge of this genus,especially of those species endemic to china that have often been excluded from previous *** spite of a few recent studies on the phylogeny and classification of the Chinese Bupleurum,the most essential problem of species delimitation still remains *** re-evaluate the taxonomy of the Chinese Bupleurum using morphological and molecular *** observations of living plants growing the field and herbarium specimens were made to understand the morphological variation and to ensure species identification for the molecular *** analyses were carried out on sequence data of nuclear ribosomal internal transcribed spacer(nrITS),trnH-psbA,and matK,using parsimony and Bayesian approaches to evaluate species *** of both nrITS and combined datasets of the three regions revealed the following results:(i)the Chinese Bupleurum species were divided into two major lineages;and(ii)most species were well defined,but some traditional inter-and infraspecific relationships were not *** results,along with the results of previous works support that the Chinese Bupleurum species were derived from two different lineages and should be placed in Neves and Watson’s subgenus *** detailed taxonomic re-assessment of several Chinese species resulted in new taxonomic recombinations with rank changes for three species:Bupleurum tenerum,***,and ***;new combination for one variety,*** ***;and the description of one variety and one species,*** *** and ***.

关键词： Chinese Bupleurum chloroplast sequences(trnH-psbA matK) morphology nrITS phylogenetic analyses taxonomy and new species.

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Integrated optimization methods in multisensor decision and estimation fusion

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Science china(Information Sciences) 2012年第3期55卷 545-550页

作者： LUO YingTing, SHEN XiaoJing & ZHU YunMin college of Mathematics, sichuan university chengdu, 610064. china college of Mathematics Sichuan University Chengdu China

This paper presents a significant integrated optimization point of view behind the following three successful decision and estimation fusion results: 1) a unified fusion rule for networked sensor decision systems; 2) optimal sensor data quantization for estimation fusion and 3) integrated multi-target data association tracking systems. More precisely speaking, the integrated optimization method in 1) derives a unified objective function optimizing only sensor rules given a unified fusion rule; the method in 2) derives a unified objective function optimizing both the sensor quantization rule and the final estimation in the MSE sense, and the method in 3) integrates all associated targets and their valid observations into a whole random measurement matrix dynamic system so that the optimal random matrix Kalman filtering can be applied to estimate the states of all associated targets.

关键词： integrated optimization decision fusion estimation fusion data association

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Notes on the Borwein-Choi Conjecture of Littlewood Cyclotomic Polynomials

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Acta Mathematica Sinica,English Series 2009年第1期25卷 65-76页

作者： Shao Fang HONG Wei CAOMathematical college, sichuan university, chengdu 610064. P. R. china Mathematical college Sichuan University Chengdu P. R. China

Borwein and Choi conjectured that a polynomial P（x） with coefficients ±1 of degree N - 1 is cyclotomic iffP（x）=±Φp1（±x）ΦP2（±x^p1）…Φpr（±x^p1p2…pr-1）,where N = P1P2 … pτ and the pi are primes, not necessarily distinct. Here Φ（x）：= （x^p - 1）/（x - 1） is the p-th cyclotomic polynomial. They also proved the conjecture for N odd or a power of 2. In this paper we introduce a so-called E-transformation, by which we prove the conjecture for a wider variety of cases and present the key as well as a new approach to investigate the coniecture.

关键词： cyclotomic polynomial Littlewood polynomial E-transformation Ramanujan sum least element

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QUANTITATIVE CHARACTERIZATION OF STRESS-STRAIN HYSTERESIS LOOPS OF Cu-Zn-Al SHAPE MEMORY ALLOY

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 97-102页

作者： Y.F. Guo, Y.Z. Huo, C.T. Zeng, X.T. Zu (Department of Metal Materials, sichuan university, chengdu 61.065, china) (Department of physics, sichuan university, chengdu 610064. china) Dept. of Metal Mat. Sichuan Univ. Chengdu 610065 China

A six-parameter mathematical model was introduced to simulate the stress-strain hysteresis and the sinner hysteresis of polycrystalline shape memory alloys (SMAs). By the comparison with experiments of Cu-Zn-Al SMA, it was shown that the model could be used to calculate the stress-strain relations with rather good accuracy. Moreover, it was found that the six parameters introduced in this paper represented the characteristics of the stress-strain hysteresis of polycrystalline SMAs and could be used to characterize the hysteresis quantitatively.

关键词： Characterization Hysteresis Shape memory effect Strain Stresses Zinc alloys

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Theoretical study on the hydrolysis mechanism of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine

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Science china Chemistry 2008年第10期51卷 911-917页

作者： ZHANG Chang1 & XUE Ying2? 1 college of Chemistry and Environment Protection Engineering, Southwest university for Nationalities, chengdu 61004., china 2 college of Chemistry, sichuan university, chengdu 610064. china college of Chemistry and Environment Protection Engineering Southwest University for Nationalities Chengdu China college of Chemistry Sichuan University Chengdu China

The hydrolysis mechanisms of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the density functional theory B3LYP/6-31+G(d, p) method. Two possible reaction pathways in the title reaction were considered. In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C—N single bond first (path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3LYP/6-31+G(d, p) level of theory based on the po-larizable continuum model (CPCM). In water the first mechanism (path A) is also favored.

关键词： N N-dimethyl-N′-(2′ 3′-dideoxy-3′-thiacytidine)formamidine hydrolysis solvent effect B3LYP polarizable continuum model

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Effect of rare earths on phase transformation in as-cast ZA27 alloy dur-ing compressive creep

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Rare Metals 2003年第4期22卷 259-264页

作者： WEIXiaowei SHENBaoluo DepamnentofAppliedphysics UniversityofElectronicScienceandTechnologyofChinaChengdu610045China DeparlanentofMetalScience SichuanUniversityChengdu610065China

The effect of the mixed rare earths of Ce on the phase transformation in ascast ZA 27 alloy during compressive was investigated under 37 MPa and at 160 deg C by X-raydiffraction technique and SEM. The results showed that the as cast microstructure of ZA 27-RE alloyconsisted of a dendritic Al-rich alpha' surrounded by Zn-rich beta' phase, interdendritic epsilonphase and Zn-rich eta phase together with a complex Z phase which was a complex constitute compound,(RE,Cu)Al_5Zn_(16), dispersed in crystal interfaces or branch crystal interfaces and stable duringcompressive creep test at 160 deg C. The phase transformations of ZA 27-RE alloy, decomposition ofbeta' phase arid four transformation, were delayed by the addition of rare earths, also the lamellarstructure and the spheroidized structure in ZA 27-RE alloy were finer than in ZA 27 alloy duringcompressive creep test at 160 deg C at the same creep time, and the compressive creep resistance ofZA 27-RE alloy was higher than that of ZA 27 alloy.

关键词： microstructure change compressive creep rare earths ZA 27 alloy

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Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1,3, SUN Weiguo1,2 & FENG Hao1 1. Institute of physics, sichuan university, chengdu 61.065, china 2. {4. of Chemical Engineering, sichuan university, chengdu 61.065, china 3. Mianyang Teacher抯 {4., Mianyang 621000, china Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) Institute of physics Sichuan University Chengdu China Mianyang Teacher's college Mianyang China college of Chemical Engineering Sichuan University Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2π state of CO+, the X2∑ g + state of Li 2 + , the X2∑ g + state of He 2 + , the 12∏u state of Na 2 + , the A2∏u state of N 2 + , the X1∑+ state of KrH+, the X2∑+ state of SiO+ and the A2π state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.

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Constructing globally consecutive 3D conductive network using P-doped biochar cotton fiber for superior performance of silicon-based anodes

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Journal of Materials Science & Technology 2024年第6期173卷 181-191页

作者： Jun Cao Jianhong Gao Kun Wang Zhuoying Wu Xinxin Zhu Han Li Min Ling chengdu Liang Jun Chen Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Institute of Zhejiang university-Quzhou Zheda Road 99Quzhou 324000China

The inferior conductivity and drastic volume expansion of silicon still remain the bottleneck in achieving high energy density Lithium-ion Batteries(LIBs).The design of the three-dimensional structure of electrodes by compositing silicon and carbon materials has been employed to tackle the above challenges,however,the exorbitant costs and the uncertainty of the conductive structure persist,leaving ample room for ***,silicon nanoparticles were innovatively composited with eco-friendly biochar sourced from cotton to fabricate a 3D globally consecutive conductive *** network serves a dual purpose:enhancing overall electrode conductivity and serving as a scaffold to maintain electrode *** conductivity of the network was further augmented by introducing P-doping at the optimum doping temperature of 350℃.Unlike the local conductive sites formed by the mere mixing of silicon and conductive agents,the consecutive network can affirm the improvement of the conductivity at a macro ***,first-principle calculations further validated that the rapid diffusion of Li^(+)is attributed to the tailored electronic microstructure and charge rearrangement of the *** prepared consecutive conductive Si@P-doped carbonized cotton fiber anode outperforms the inconsecutive Si@Graphite anode in both cycling performance(capacity retention of 1777.15 mAh g^(-1) vs.682.56 mAh g^(-1) after 150 cycles at 0.3 C)and rate performance(124..24.mAh g^(-1) vs.370.28 mAh g^(-1) at 2.0 C).The findings of this study may open up new avenues for the development of globally interconnected conductive networks in Si-based anodes,thereby enabling the fabrication of high-performance LIBs.

关键词： 3D conductive network Biochar carbon-silicon anode Heteroatoms doping strategy DFT calculation Lithium-ion battery

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STABILITY RADIUS OF NON-SMOOTH PRITCHARD-SALAMON SYSTEMS AND THE ALGEBRAIC RICCATI EQUATION

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Journal of Systems Science & Complexity 2009年第2期22卷 220-227页

作者： Weisheng JIANG Falun HUANG Tingyu ZHU college of Mathematics and physics Chongqing University Chongqing 400044 China. college of Mathematics Sichuan University Chengdu 610064 China.

The authors discuss the stability radius of the non-smooth Pritchard-Salamon systemsunder structured perturbations.A formula for the stability radius in terms of t he norm of a certaininput-output operator is ***,the ... 详细信息

关键词： Operator Riccati equation Pritehard-Salamon system stability radius.

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SYSTEM OF GENERALIZED VECTOR QUASI-EQUILIBRIUM PROBLEMS ON PRODUCT FC-SPACES

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Acta Mathematica Scientia 2007年第3期27卷 522-534页

作者：丁协平 college of Mathematics and Software Science Sichuan Normal University

By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equilibrium existence theorems, some new existence theorems of solutions for the system of generalized vector quasi-equilibrium problems are established in noncompact product FC-spaces. These results improve and generalize some recent results in literature to product FC-spaces without any convexity structure.

关键词： Maximal element generalized game equilibrium system of generalized vector quasi-equilibrium problems FC-spaces

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