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Simulation and modal analysis of the uplift device of a sugarcane harvester using virtual prototype technology
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作者 胡迎春 《Journal of Chongqing University》 CAS 2007年第3期187-191,共5页
A three-dimensional model of the uplift device of a sugarcane harvester was built up in Pro/Engineer. Simulation and evaluation of its motional and dynamic performance were performed with the automatic dynamic analysi... A three-dimensional model of the uplift device of a sugarcane harvester was built up in Pro/Engineer. Simulation and evaluation of its motional and dynamic performance were performed with the automatic dynamic analysis of mechanical system (ADAMS). ANSYS program was applied to the structural analysis of the model. A finite element analytic model was built up with the bottom-up methodology and was meshed. The default Block Lanczos method was used to work out the native frequency. The results indicate that the five lower modes-the transpotaion wheel, the left holding device, the right holding device, the left cutter disk, and the right cutter disk- and displacement of vibratory type only slightly affect the process of sugarcane harvester and harvesting quality. So it is advisable that the optimization of the static intensity other than the dynamic stiffness of uplift device be executed. 展开更多
关键词 dynamic simulation modal analysis displacement of vibratory type harvesting quality
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Time-Dependent Variational Approach to Ground-State Phase Transition and Phonon Dispersion Relation of the Quantum Double-Well Model 被引量:3
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作者 钟红伟 徐海清 黄乒花 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第8期2758-2761,共4页
The ground-state phase transition and the phonon dispersion relation of the quantum double-well model are studied by means of the time-dependent variational approach combined with a Hartree-type many-body trial wavefu... The ground-state phase transition and the phonon dispersion relation of the quantum double-well model are studied by means of the time-dependent variational approach combined with a Hartree-type many-body trial wavefunction. The single-particle state is taken to be a frozen Jackiw-Kerman wavefunction. Under the condition of minimum uncertainty relation, we obtain an effective classical Hamiltonian for the system and equations of motion for the particle's expectation values. It is shown that the effective substrate potential transits from a symmetric double-well potential to a symmetric single-well potential, and the ground state exhibits a transition from a broken symmetry phase to a restored symmetry phase as increasing the strength of quantum fluctuations. We also obtain the phonon dispersion relations and the phonon gaps at the two phases. 展开更多
关键词 FIELD-THEORY POLYACETYLENE DYNAMICS SOLITONS APPROXIMATION FLUCTUATIONS PRESSURE CHAINS ICE
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The Determination of Iodide Based on a Flow-injection Coupling Irreversible Biamperometry 被引量:3
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作者 Li Jun LI Hao CHENG +5 位作者 Wen Yi HUANG Hong Xing KONG Jian Ling WU Jian Ping LU Wei GAO Jun Feng SONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第12期1629-1632,共4页
A novel flow-injection irreversible biamperometric method is described for the direct determination of iodide. The method is based on electrochemical oxidation of iodide at the gold electrode and the reduction of perm... A novel flow-injection irreversible biamperometric method is described for the direct determination of iodide. The method is based on electrochemical oxidation of iodide at the gold electrode and the reduction of permanganate at the platinum electrode to form an irreversible biamperometric detection system. Under the applied potential difference of 0 V, in the 0.05 mol/L sulfuric acid, iodidecan be determined over the range 4.00×10^-7-1.00×10^-5 mol/L with a sampling frequency of 120 samples per hour. The detection limit for I- is 3.0×10^-7 mol/L and the RSD for 40 replicate determinations of 4.0×10^-5 mol/L potassium iodide is 1.68%. The new method was applied to the analysis of iodide in table salt with satisfactory results. 展开更多
关键词 IODIDE flow injection irreversible biamperometry gold electrode platinum electrode
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Process Reengineering of Cold Chain Logistics of Agricultural Products Based on Low-carbon Economy 被引量:7
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作者 GUO Hong-xia SHAO Ming 《Asian Agricultural Research》 2012年第2期59-62,共4页
Through the process analysis of cold chain logistics of agricultural products,we find that cold chain logistics of agricultural products contradict the development model of low-carbon economy to some extent.We apply t... Through the process analysis of cold chain logistics of agricultural products,we find that cold chain logistics of agricultural products contradict the development model of low-carbon economy to some extent.We apply the development idea of low-carbon economy,introduce the thirdparty logistics companies,establish distribution center of cold chain logistics of agricultural products,and strengthen information sharing,to reengineer the process of cold chain logistics of agricultural products in China.The results show that applying low-carbon economy to process reengineering of cold chain logistics of agricultural products,has advantages of increasing added value of products,promoting scale merit and abating lag,plays a role in promoting emission reduction,high efficiency and environmental protection in the process of cold chain logistics of agricultural products in China. 展开更多
关键词 Low carbon economy Business process reengineering Agricultural products Cold chain logistics
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Determination of chlorogenic acid by flow injection irreversible biamperometry 被引量:3
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作者 Li Jun Li Qi Feng Chen +5 位作者 Lai Bo Yu Zhao Heng Zhong Jun Feng Hao Cheng Hong Xing Kong Jian Ling Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第4期431-434,共4页
A flow injection irreversible biamperometric method for the determination of chlorogenic acid is described. The proposed method is based on the electrochemical oxidation of chlorogenic acid at pretreated platinum elec... A flow injection irreversible biamperometric method for the determination of chlorogenic acid is described. The proposed method is based on the electrochemical oxidation of chlorogenic acid at pretreated platinum electrode and the reduction of permanganate at another electrode to form an irreversible biamperometric detection system. Under the external potential difference (z^v) of 0 V, in the 0.05 mol/L sulfuric acid, chlorogenic acid can be determined over the range 0.8-120 mg/L with a sample measurement frequency of 80 samples/h. The detection limit is 0.18 mg/L. The proposed method exhibits the satisfactory reproducibility with a relative standard derivation (R.S.D.) of 2.21% for 19 successive determinations of 40 mg/L. 展开更多
关键词 Flow injection Irreversible biamperometry Chlorogenic acid HONEYSUCKLE
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Synthesis of mesoporous cerium-zirconium mixed oxides by hydrothermal templating method 被引量:3
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作者 王曼娟 古映莹 +2 位作者 秦利平 李金林 徐文泱 《Journal of Central South University of Technology》 EI 2008年第6期796-800,共5页
Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal tempera... Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm3/g. 展开更多
关键词 cerium-zirconium mixed oxides hydrothermal method cetyl trimethyl ammonium bromide MESOPORE template
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Determination of levodopa in pharmaceutical preparations by irreversible biamperometry 被引量:2
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作者 Li Jun Li Qi Feng Chen +2 位作者 Hao Cheng Lai Bo Yu Jian Ling Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第6期703-706,共4页
Based on the electrocatalytic oxidation of levodopa at gold electrode and the reduction of permanganate at platinum electrode, a novel flow injection irreversible biamperometric method is developed for the determinati... Based on the electrocatalytic oxidation of levodopa at gold electrode and the reduction of permanganate at platinum electrode, a novel flow injection irreversible biamperometric method is developed for the determination of levodopa under the potential difference of 0 V imposed between two electrodes. In H2SO4 solution, the linear relationships between currents and the concentrations of levodopa are obtained in the range from 0.04 mg/L to 20 mg/L with the detection limit of 0.012 mg/L. The proposed method is applied to the determination of levodopa in pharmaceutical preparations. 展开更多
关键词 Flow injection LEVODOPA Irreversible biamperometry Gold electrode Platinum electrode
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Gluonic Origin and Glueball Nature of Pomeron 被引量:2
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作者 ZHOU Li-Juan HE Xiao-Rong MA Wei-Xing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期509-513,共5页
The Pomeron-nucleon coupling vertex is theoretically derived from the fundamental theory of strong interaction QCD. The empirical vertex βγ^μF1 (t) used commonly in diffractive processes with a coupling strength ... The Pomeron-nucleon coupling vertex is theoretically derived from the fundamental theory of strong interaction QCD. The empirical vertex βγ^μF1 (t) used commonly in diffractive processes with a coupling strength β = 6.0 GeV^-1 is initially obtained from QCD theoretically. Our study not only reproduces the Pomeron-nucleon coupling from QCD but also clearly shows the gluonlc origin and glueball nature of Pomeron, which is a longstanding puzzle. From this investigation, we claim that Pomeron can be regarded as a Reggeized tensor glueball ζ(2230) with quantum numbers of I^GJ^PC = 0+2++. Since the tensor glueball ζ(2230) lies on the Pomeron trajectory αp(t = Mζ^2) = 2, the longstanding puzzle that no physical particle lies on the Pomeron trajectory, αp(t) = 1.08 + 0.20 GeV^-2 .t, seems to be solved. 展开更多
关键词 POMERON GLUON GLUEBALL QCD coupling vertex of Pomeron
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Synthesis and electrochemical performance of Li_3V_2(PO_4)_3 by optimized sol-gel synthesis routine 被引量:2
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作者 张倩 李艳红 +2 位作者 钟胜奎 肖新和 颜波 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第8期1545-1549,共5页
Li3V2(PO4)3 samples were synthesized by sol-gel route and high temperature solid-state reaction. The influence of Li3V2(PO4)3 as cathode materials for lithium-ion batteries on electrochemical performances was inve... Li3V2(PO4)3 samples were synthesized by sol-gel route and high temperature solid-state reaction. The influence of Li3V2(PO4)3 as cathode materials for lithium-ion batteries on electrochemical performances was investigated. The structure of Li3Va(PO4)3 as cathode materials for lithium-ion batteries and morphology of Li3V2(PO4)3 were characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). Electrochemical performances were characterized by charge/discharge and AC impedance measurements. Li3V2(PO4)3 with smaller grain size shows better performances in terms of the discharge capacity and cycle stability. The improved electrochemical properties of Li3V2(PO4)3 are attributed to the refined grains and enhanced electrical conductivity. AC impedance measurements also show that the Li3V2(PO4)3 synthesized by sol-gel route exhibits significantly decreased charge-transfer resistance and shortened migration distance of lithium ions. 展开更多
关键词 lithium ion batteries cathode material Li3V2(PO4)3 sol-gel method
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Non-perturbative Aspects of QCD and Parameterized Quark Propagator 被引量:2
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作者 ZHOU Li-Juan GU Yun-Ting +2 位作者 MA Wei-Xing MENG Cheng-Ju PAN Ji-Huan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期181-188,共8页
Based on the Global Color Symmetry Model, the non-perturbative Q, CD vacuum is investigated in the parameterized fully dressed quark propagator. Our theoretical predictions for various quantities characterized the QCD... Based on the Global Color Symmetry Model, the non-perturbative Q, CD vacuum is investigated in the parameterized fully dressed quark propagator. Our theoretical predictions for various quantities characterized the QCD vacuum are in agreement with those predicted by many other phenomenologieal QCD inspired models. The successful predictions clearly indicate the extensive validity of our parameterized quark propagator used here. A detailed discussion on the arbitrariness in determining the integration cut-off parameter ofμ in calculating QCD vacuum condensates and a good method, which avoided the dependence of calculating results on the cut-off parameter is also strongly recommended to readers. 展开更多
关键词 global color symmetry model parameterized quark propagator non-perturbative QCD vacuumand vacuum condensate
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Dynamical Running Mass of Quark in the Dyson-Schwinger Equation Approach 被引量:1
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作者 MA Wei-Xing SHEN Peng-Nian ZHOU Li-Juan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第11期571-576,共6页
Based on the Dyson-Schwinger equations of QCD in the "rainbow" approximation, the fully dressed quarkpropagator Sf(p) is investigated, and then an algebraic parametrization form of the propagator is obtained... Based on the Dyson-Schwinger equations of QCD in the "rainbow" approximation, the fully dressed quarkpropagator Sf(p) is investigated, and then an algebraic parametrization form of the propagator is obtained as a solutionof the equations. The dressed quark amplitudes Af and Bf built up the fully dressed quark propagator and the dynamicalrunning masses Mf defined by Af and Bf for light quarks u, d and s are calculated, respectively. Using the predictedrunning masses Mf, quark condensates <0|q(0)q(0)|0> = -(0.255 GeV)a for u, d quarks, and <0|s s|0> = 0.8<0|q(0)q(0)]0)for s quark, and experimental pion decay constant fπ = 0.093 GeV, the masses of Goldstone bosons K, π, and η are alsoevaluated. The numerical results show that the masses of quarks are dependent on their momentum p2. The fully dressedquark amplitudes Af and Bf have correct behaviors which can be used for many purposes in our future researches onnonperturbative QCD. 展开更多
关键词 Dyson-Schwinger equations QUARK propagator QUARK mass the MASSES of Goldstone BOSONS
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Effect of Microwave Processing on Aluminate Cement Clinkering 被引量:1
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作者 董健苗 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第2期77-79,共3页
When raw materials were preheated to 1000-1300 ℃ by electricity and microwave was inputted for 1 min 5 s-4 mins, then alunminate clinkers were obtained. The f-CaO contents,XRD patterns and lithofacies analysis show t... When raw materials were preheated to 1000-1300 ℃ by electricity and microwave was inputted for 1 min 5 s-4 mins, then alunminate clinkers were obtained. The f-CaO contents,XRD patterns and lithofacies analysis show that the microwave processing accelerates the clinkering reaction,and Fe_2O_3 is contributed to the aluminate cement clinkering. The appearance of liquid phase in process of microwave heating increases the microwave absorbability of materials greatly. 展开更多
关键词 microwave promoting clinkering aluminate cement F-CAO X-ray diffraction lithofacies photo
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A variational solution of 2-D sound-structure interaction problems 被引量:1
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作者 Yuying Huang Haidong Su Yu Xiang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第2期127-131,共5页
Based on the fluid-structure coupling theory, a localized variational principle for analyzing the sound radiation from elastic structure submerged in water due to harmonic excitations is presented. It will be a powerf... Based on the fluid-structure coupling theory, a localized variational principle for analyzing the sound radiation from elastic structure submerged in water due to harmonic excitations is presented. It will be a powerful tool to formulate various numerical methods for steady response of structural-acoustic systems. By means of this variational principle a hybrid element method, in which an analytical solution valid in most of the surrounding water is incorporated with finite elements distributed in the structure and its neighboring water, is devised. Computational examples are then given to demonstrate its high accuracy and time saving. 展开更多
关键词 Variational principle Acoustic radiation Fluid-structure coupling vibration Hybrid element method
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New matrix method for analyzing vibration and damping effect of sandwich circular cylindrical shell with viscoelastic core 被引量:1
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作者 向宇 黄玉盈 +2 位作者 陆静 袁丽芸 邹时智 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第12期1587-1600,共14页
Based on the linear theories of thin cylindrical shells and viscoelastic materials, a governing equation describing vibration of a sandwich circular cylindrical shell with a viscoelastic core under harmonic excitation... Based on the linear theories of thin cylindrical shells and viscoelastic materials, a governing equation describing vibration of a sandwich circular cylindrical shell with a viscoelastic core under harmonic excitation is derived. The equation can be written as a matrix differential equation of the first order, and is obtained by considering the energy dissipation due to the shear deformation of the viscoelastic core layer and the interaction between all layers. A new matrix method for solving the governing equation is then presented With an extended homogeneous capacity precision integration approach. Having obtained these, vibration characteristics and damping effect of the sandwich cylindrical shell can be studied. The method differs from a recently published work as the state vector in the governing equation is composed of displacements and internal forces of the sandwich shell rather than displacements and their derivatives. So the present method can be applied to solve dynamic problems of the kind of sandwich shells with various boundary conditions and partially constrained layer damping. Numerical examples show that the proposed approach is effective and reliable compared with the existing methods. 展开更多
关键词 constrained layer damping matrix differential equation of first order circular cylindrical shell high precision integration approach
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Asymptotic behavior of 2D generalized stochastic Ginzburg-Landau equation with additive noise 被引量:1
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作者 李栋龙 郭柏灵 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第8期945-956,共12页
The 2D generalized stochastic Ginzburg-Landau equation with additive noise is considered. The compactness of the random dynamical system is established with a priori estimate method, showing that the random dynamical ... The 2D generalized stochastic Ginzburg-Landau equation with additive noise is considered. The compactness of the random dynamical system is established with a priori estimate method, showing that the random dynamical system possesses a random attractor in H^1 0. 展开更多
关键词 2D generalized stochastic Ginzburg-Landau equation random dynamical system random attractor
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ALL MEROMORPHIC SOLUTIONS OF AN AUXILIARY ORDINARY DIFFERENTIAL EQUATION AND ITS APPLICATIONS 被引量:1
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作者 袁文俊 熊维玲 +1 位作者 林剑鸣 吴永洪 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1241-1250,共10页
In this paper, we first employ the complex method to deritive all meromorphic solutions of an auxiliary ordinary differential equation, and then find all meromorphic exact solutions of the modified ZK equation, modifi... In this paper, we first employ the complex method to deritive all meromorphic solutions of an auxiliary ordinary differential equation, and then find all meromorphic exact solutions of the modified ZK equation, modified KdV equation, nonlinear Klein-Gordon equation and modified BBM equation. Our work shows that there exist some classes of rational solutions wr,2 (z) and simple periodic solutions ws,1 (z) which are new and are not degenerated successively to by the elliptic function solutions. 展开更多
关键词 differential equation exact solution meromorphic function elliptic function
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Determination of Metamizole Sodium by Cyclic Voltammetry Under Microwave Activation 被引量:1
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作者 LI Li-jun CHENG Long-jun +3 位作者 CAI Zhuo LAN Su-mei GUO Xiao-fei LI Yan-qing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第4期537-540,共4页
Microwave radiation was applied to the detection of metamizole sodium by cyclic voltammetry. The electrochemical characteristics of metamizole sodium were studied by cyclic voltammetry at GC electrode under microwave ... Microwave radiation was applied to the detection of metamizole sodium by cyclic voltammetry. The electrochemical characteristics of metamizole sodium were studied by cyclic voltammetry at GC electrode under microwave radiation and a considerable current enhancement was observed for metamizole sodium in aqueous 0.05 mol/L H2SO4. Under the optional conditions, metamizole sodium was determined in the absence and presence of microwave activation. In the absence of microwave activation cyclic voltammogram of metamizole sodium shows good linear relationship in a concentration range of 8.0×10^-5-1.0×10^-3 mol/L in aqueous 0.05 mol/L H2SO4 with a detection limit of 6.75× 10^-6 mol/L(S/N=3) and the equation of linear regression is Ip=12.973c-0.1905(R^2=0.9996, n=6); in the presence of 80 W microwave activation cyclic voltammogram of metamizole sodiumin shows good linear relationship in a concentration range of 4.0× 10^-5-1.0×10^-3 mol/L in aqueous 0.05 mol/L H2SO4 with a detection limit of 4,41 × 10^-6 mol/L(S/N=3) and the equation of linear regression is Ip=25.107c-0.1193(R^2=0.9973, n=7). The current in the presence of 80 W microwave activation increases to about 2 orders of magnitude compared with that in the absence of microwave activation. The proposed method in the presence of microwave activation showed high selectivity and sensitivity, and the sampling of the disposal method is simple. The method was verified by the determination of Metamizole Sodium tablet with satisfactory results. 展开更多
关键词 MICROWAVE Metamizole sodium Cyclic voltammetry
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Gasser-Leutwyler Coefficients of Chiral Lagrangian for Pseudoscalar Goldstone Bosons in Dyson-Schwinger Equations 被引量:1
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作者 GU Yun-Ting QIN Song-Mei +1 位作者 ZHOU Li-Juan MA Wei-Xing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1205-1210,共6页
Based on the Dyson-Schwinger equations of quark propagator in rainbow truncation with an effective gluonpropagator,the ten unknown Gasser-Leutwyler coefficients of the chiral Lagrangian for pseudoscalar Goldstone boso... Based on the Dyson-Schwinger equations of quark propagator in rainbow truncation with an effective gluonpropagator,the ten unknown Gasser-Leutwyler coefficients of the chiral Lagrangian for pseudoscalar Goldstone bosonsare predicted.The predicted values of L_i with i=1,2,...,10 are in a reasonable agreement with empirical values usedwidely in literature,and the values predicted by many other theoretical models with QCD characteristics. 展开更多
关键词 chiral perturbation theory Gasser-Leutwyler coefficient Dyson-Schwinger equation
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Ratio of Real to Imaginary for pp and pp Elastic Scatterings in QCD Inspired Model 被引量:1
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作者 LU Juan MA Wei-Xing HE Xiao-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期550-554,共5页
We use the QCD inspired model to analyze the ratio of the real to the imaginary for pp and pp elastic scatterings. A calculation for the ratio of the real to the imaginary is performed in which the contributions from ... We use the QCD inspired model to analyze the ratio of the real to the imaginary for pp and pp elastic scatterings. A calculation for the ratio of the real to the imaginary is performed in which the contributions from gluongluon interaction, quark-quark interaction, quark-gluon interaction, and odd eikonal profile function are included. Our results show that the QCD inspired model gives a good fit to the LHC experimental data. 展开更多
关键词 QCD inspired model eikonal profile function ratio of real to imaginary
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Quark Mass Dependence of Nucleon Magnetic Moment and Charge Radii 被引量:1
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作者 MA Wei-Xing ZHOU Li-Juan +1 位作者 GU Yun-Ting PING Rong-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期333-336,共4页
Understanding hadron structure within the framework of QCD is an extremely challenging problem. Our purpose here is to explain the model-independent consequences of the approximated chiral symmetry of QCD for two famo... Understanding hadron structure within the framework of QCD is an extremely challenging problem. Our purpose here is to explain the model-independent consequences of the approximated chiral symmetry of QCD for two famous results concerning the quark structure of the nucleon. We show that both the apparent success of the constituent quark model in reproducing the ratio of proton to neutron magnetic moments and the apparent success of the Foldy term in reproducing the observed charge radius of the neutron are coincidental. That is, a relatively small change of the current quark mass would spoil both results. 展开更多
关键词 quark mass nucleon magnetic moment nucleon charge radius
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