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气固多相反应流中的煤粉颗粒相能量方程 被引量:1
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作者 张 健 朱成凯 周力行 《力学与实践》 CSCD 北大核心 2002年第3期10-12,共3页
为了合理地预测燃烧装置内煤粉颗粒的燃烧行为,从多相反应流中一般形式的颗粒相能量方程出发,导出了煤粉颗粒相的能量方程,给出了方程中反映相变引起的气固相间相互作用的源相的具体表达式,与此同时还给出了气相能量方程中代表相间相互... 为了合理地预测燃烧装置内煤粉颗粒的燃烧行为,从多相反应流中一般形式的颗粒相能量方程出发,导出了煤粉颗粒相的能量方程,给出了方程中反映相变引起的气固相间相互作用的源相的具体表达式,与此同时还给出了气相能量方程中代表相间相互作用的颗粒源项的一种计算式. 展开更多
关键词 气固多反应流 煤粉颗粒 相能量方程 相能量方程 燃烧理论
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Fe-Mn 二元系中相能量 MEAM 研究 被引量:2
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作者 戎咏华 赵恒北 +1 位作者 郭正洪 徐祖耀 《上海交通大学学报》 EI CAS CSCD 北大核心 1998年第2期62-64,76,共4页
应用修正嵌入原子法(MEAM)研究了Fe-Mn二元合金中γ相(fcc)和α(bcc)随Mn含量变化的不同能量,它们的能量变化趋势与Fe-Mn二元相图的推测结果一致.由此表明,用MEAM法研究Fe-Mn二元系中两种立方... 应用修正嵌入原子法(MEAM)研究了Fe-Mn二元合金中γ相(fcc)和α(bcc)随Mn含量变化的不同能量,它们的能量变化趋势与Fe-Mn二元相图的推测结果一致.由此表明,用MEAM法研究Fe-Mn二元系中两种立方相的能量是有效的. 展开更多
关键词 修正嵌入原子法 相能量 铁锰合金 二元合金
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利用固相能量守恒定律判定煤炭最短发火期
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作者 朱云辉 程功林 +1 位作者 方良才 夏仕伯 《煤矿开采》 北大核心 2010年第6期20-22,共3页
利用固相能量守恒定律判定煤炭最短发火期技术,建立简便实效的数学模型,并与使用TGA/SDTA851 e同步热分析仪所得的数据进行拟合,对煤的实验最短发火期进行测算,大幅提高最短发火期预测的效率和精度,对我国研究煤自燃预测预报和煤炭自燃... 利用固相能量守恒定律判定煤炭最短发火期技术,建立简便实效的数学模型,并与使用TGA/SDTA851 e同步热分析仪所得的数据进行拟合,对煤的实验最短发火期进行测算,大幅提高最短发火期预测的效率和精度,对我国研究煤自燃预测预报和煤炭自燃预防具有重要的参考价值。 展开更多
关键词 相能量守恒定律 最短发火期 数学模型
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远砂坝能量相单元沉积模式及流动单元划分 被引量:7
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作者 马世忠 葛政俊 +3 位作者 王继平 王一博 占永江 刘吉余(审稿) 《大庆石油学院学报》 CAS 北大核心 2006年第2期9-12,143,共4页
基于单砂体内部特征(岩性、物性、厚度及其分布等)控制着驱油效率与波及体积,且又受控于其沉积过程,根据单砂体成因、形成过程,确定了微相单砂体及其内部能量单元的沉积模式,进而实现单砂体内流动单元的划分.以杏南PⅠ4单元远砂坝微相为... 基于单砂体内部特征(岩性、物性、厚度及其分布等)控制着驱油效率与波及体积,且又受控于其沉积过程,根据单砂体成因、形成过程,确定了微相单砂体及其内部能量单元的沉积模式,进而实现单砂体内流动单元的划分.以杏南PⅠ4单元远砂坝微相为例,建立了远砂坝能量相单元沉积模式,在此控制下,将远砂坝划为4类流动单元6级能量单元,并将远砂坝内部能量相单元、形成机制、流动单元有机结合,揭示了远砂坝内部流动单元平面分布规律. 展开更多
关键词 远砂坝 级单砂体 能量单元 沉积模式 流动单元
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最小能量函数法求解多元相平衡 被引量:2
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作者 杜建华 胡雪蛟 刘翔 《大连理工大学学报》 CAS CSCD 北大核心 2001年第z1期1-4,共4页
根据孤立系统平衡时熵最大原理 ,利用已有的优化工具包 ,在一定温度和压力下 ,使系统吉布斯自由能最小化 ,求解多元相平衡问题 .作为实例 ,给出了绿色制冷剂 R32与 R1 34 a混合体系在不同压力 ( 2 0 k Pa~ 5 MPa)下平衡组分的计算结果 ... 根据孤立系统平衡时熵最大原理 ,利用已有的优化工具包 ,在一定温度和压力下 ,使系统吉布斯自由能最小化 ,求解多元相平衡问题 .作为实例 ,给出了绿色制冷剂 R32与 R1 34 a混合体系在不同压力 ( 2 0 k Pa~ 5 MPa)下平衡组分的计算结果 ;该结果同已有的实验数据吻合 .由于该方法的基础性和一般性 ,有望成为包括流体流动、浓度扩散、物质相变以及化学反应在内的复杂过程的统一的热力学处理方法 . 展开更多
关键词 平衡/最小能量 非线性优化
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基于下垂移相的三端口直流能量路由器功率协调控制策略 被引量:13
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作者 涂春鸣 栾思平 +1 位作者 肖凡 兰征 《电网技术》 EI CSCD 北大核心 2019年第11期4105-4114,共10页
针对应用于多个直流微网间互联的三端口直流能量路由器,分析了三端口直流微网的运行状态和能量路由器各端口的工作模式。在此基础上,分析了单母线直流微网传统下垂控制存在的问题和局限性;为此提出基于标幺化下垂移相的三端口直流能量... 针对应用于多个直流微网间互联的三端口直流能量路由器,分析了三端口直流微网的运行状态和能量路由器各端口的工作模式。在此基础上,分析了单母线直流微网传统下垂控制存在的问题和局限性;为此提出基于标幺化下垂移相的三端口直流能量路由器功率协调控制策略,实现能量在多个直流微网间的合理分配和减小各直流微网中的母线电压偏差;通过将单母线直流微网的电压-有功功率下垂特性标幺化,从而得到不同电压等级直流子微网间需交换的能量,无需切换三端口直流能量路由器端口工作模式便可确保各直流子微网在正常、不正常和功率故障状态下的功率支撑。仿真结果验证了所提下垂移相功率协调控制策略的正确性和可行性。 展开更多
关键词 直流微网 三端口能量路由器:下垂移 功率协调控制
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Laws of strata energy release and corresponding safety warning system in metal mine 被引量:5
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作者 刘志祥 郭永乐 +1 位作者 刘超 卢俊华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2508-2512,共5页
The strata deformation in mining area was monitored in Dabaoshan copper-iron mine,and an analytical method of strata energy release was put forward.On the basis of chaotic theory,by reconstructing the phase space for ... The strata deformation in mining area was monitored in Dabaoshan copper-iron mine,and an analytical method of strata energy release was put forward.On the basis of chaotic theory,by reconstructing the phase space for time series data of strata energy release,the saturated embedding dimension and the correlation dimension of the dynamic system were obtained to be 4 and 1.212 8,respectively,and the evolution laws of distances between phase points of strata energy release in the phase space were revealed.With grey theory,a prediction model of strata energy release was set up,the maximum error of which was less than 6.7%.The results show that there are chaotic characters in strata energy release during mining;after reconstructing phase space,the subtle changing characteristics of energy release can be magnified,and the internal rules can be fully demonstrated.According to the laws,a warning system for strata stability in mining area was established to provide a technical safeguard for safe mining. 展开更多
关键词 strata energy release phase space reconstruction grey theory safety warning system
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Energies and Transition Rates of Low-Lying Excited States for Beryllium
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作者 韩利红 苟秉聪 王菲 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期109-112,共4页
Low lying excited states of beryllium are calculated with multiconfiguration interaction method. The relativisitic corrections and mass polarization are included. The oscillator strength and radiation rates are also ... Low lying excited states of beryllium are calculated with multiconfiguration interaction method. The relativisitic corrections and mass polarization are included. The oscillator strength and radiation rates are also calculated. Our results are in good agreement with other theoretical data. 展开更多
关键词 oscillator strength radiation transition BERYLLIUM
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计算机辅助的胸部X线诊断
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作者 梁志刚 李坤成 《放射学实践》 2003年第9期696-696,共1页
关键词 计算机辅助 胸部 X线诊断 双重能量减法 特征分析法
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改进型McMurray-Bedford逆变电路研究
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作者 许雪生 《宁波大学学报(教育科学版)》 1988年第2期82-94,共13页
本文对改进型McMurray-Bedford逆变电路作了改进,它不需要增加元件,就可起到回收换相电感能量的目的,这比文献中见到的同样目的的电路要简单;此外,本文从逆变电路的整个网络出发,并考虑到换相电感间耦合系数K<1的实际情况,分析逆变... 本文对改进型McMurray-Bedford逆变电路作了改进,它不需要增加元件,就可起到回收换相电感能量的目的,这比文献中见到的同样目的的电路要简单;此外,本文从逆变电路的整个网络出发,并考虑到换相电感间耦合系数K<1的实际情况,分析逆变电路的换相过程,从而导出了一组换相参数。 展开更多
关键词 电压换逆变电路 相能量回收 参数的计算公式
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Influence of the Interaction Between Phonons and Coulomb Potential on the Properties of a Bound Polaron in a Quantum Dot
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作者 尹辑文 于毅夫 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1883-1887,共5页
The properties of a bound polaron in a parabolic quantum dot with weak electron-LO-phonon coupling under a Coulomb field are studied. The ground state energy of the bound polaron is derived by using a linear combinati... The properties of a bound polaron in a parabolic quantum dot with weak electron-LO-phonon coupling under a Coulomb field are studied. The ground state energy of the bound polaron is derived by using a linear combination operator and the perturbation method. The influence of the interaction between phonons with different wave vectors in the recoil process on the ground state energy of the bound polaron is discussed. Numerical calculations are performed,and the results show that the ground state energy increases significantly as the effective confinement length of the quantum dot decreases,considering of the interaction between phonons. When l0〉1.0, the influence of the interaction between phonons on the ground state energy cannot be ignored. 展开更多
关键词 parabolic quantum dot bound polaron interaction between phonons ground state energy
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A New Type of Power Clock for DSCRL Adiabatic Circuit
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作者 罗家俊 李晓民 +1 位作者 陈潮枢 仇玉林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第7期757-761,共5页
An asymmetry power clock,4 phase power clock supplying the power to the DSCRL(dual swing charge recovery logic) adiabatic circuit is presented.It is much simpler than the 6 phase power clock,symmetry power clock,us... An asymmetry power clock,4 phase power clock supplying the power to the DSCRL(dual swing charge recovery logic) adiabatic circuit is presented.It is much simpler than the 6 phase power clock,symmetry power clock,used in the DSCRL adiabatic circuit.Although the 4 phase power clock is simpler,the DSCRL adiabatic circuit still shows good performance and high efficiency of energy transfer and recovery.This conclusion has been proved by the result of the HSPICE simulation using the 0 6μm CMOS technology. 展开更多
关键词 DSCRL adiabatic circuit low power 4 phase power clock energy recover
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Comparative Investigation of Mo(CO)6 Adsorption on Clean and OxidiZed Si(111) Surfaces
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作者 姜志全 黄伟新 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第6期729-734,I0004,共7页
Mo(CO)6 adsorption on the clean, oxygen-precovered and deeply oxidized Si(lll) surfaces was comparatively investigated by high-resolution electron energy loss spectroscopy. The downward vibrational frequency shift... Mo(CO)6 adsorption on the clean, oxygen-precovered and deeply oxidized Si(lll) surfaces was comparatively investigated by high-resolution electron energy loss spectroscopy. The downward vibrational frequency shift of the C-O stretching mode in adsorbed Mo(CO)6 illustrates that different interactions of adsorbed Mo(CO)6 occur on clean Si(111) and SiO2/Si(111) surfaces, weak on the former and strong on the latter. The strong interaction on SiO2/Si(111) might lead to the partial dissociation of Mo(CO)6, consequently the formation of molybdenum subcarbonyls. Therefore, employing Mo(CO)6 as the precursor, metallic molybdenum could be successfully deposited on the SiO2/Si(111) surface but not on the clean Si(111) surface. A portion of the deposited metallic molybdenum is transformed into the MoOa on the SiO2/Si(111) surface upon heating, and the evolved MoO3 finally desorbs from the substrate upon annealing at elevated temperatures. 展开更多
关键词 Molybdenum hexacarbonyl SiO2/Si(111) Interaction High-resolution electron energy loss spectroscopy
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Heisenberg Group and Energy-Momentum Conservative Law in de-Sitter Spaces—— In Memory of the 100th Anniversary of Einstein's Special Relativity and the 70th Anniversary of Dirac's de-Sitter Spaces 被引量:9
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作者 LU Qi-Keng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期389-392,共4页
In 1935 Dirac established the physical wave equations in the de-Sitter spaces but neither energy-momentum operators nor their conservative laws were given. In this article it is proved that in the de-Sitter group ther... In 1935 Dirac established the physical wave equations in the de-Sitter spaces but neither energy-momentum operators nor their conservative laws were given. In this article it is proved that in the de-Sitter group there is a subgroup group isomorphic to the Heisenberg group and the generators of this groups are the energy-momentum operators which obey a conservative law. 展开更多
关键词 energy-momentum conservation Heisenberg grup de-Sitter space
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Performances of Five Representative Force Fields on Gaseous Amino Acids with Different Termini
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作者 陈欣 林子敬 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第2期179-186,I0001,共9页
There is a growing interest in the study of structures and properties of biomolecules in gas phase. Applications of force fields are highly desirable for the computational efficiency of the gas phase study. To help th... There is a growing interest in the study of structures and properties of biomolecules in gas phase. Applications of force fields are highly desirable for the computational efficiency of the gas phase study. To help the selection of force fields, the performances of five repre- sentative force fields for gaseous neutral, protonated, deprotonated and capped amino acids are systematically examined and compared. The tested properties include relative conforma- tional energies, energy differences between cis and trans structures, the number and strength of predicted hydrogen bonds, and the quality of the optimized structures. The results of BHandHLYP/6-311++G(d,p) are used as the references. GROMOS53A6 and ENCADS are found to perform poorly for gaseous biomoleeules, while the performance of AMBER99SB, CHARMM27 and OPLSAA/L are comparable when applicable. Considering the general availability of the force field parameters, CHARMM27 is the most recommended, followed by OPLSAA/L, for the study of biomolecules in gas phase 展开更多
关键词 CONFORMATION Relative energies Correlation coefficient Hydrogen bond Molecular mechanics
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Finite Range Effects on Fusion and/or Breakup of ~6He+^(238)U and ^(11)Li+^(208)Pb Systems 被引量:1
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作者 Sukhvinder S.Duhan Manjeet Singh +1 位作者 Rajesh Kharab H.C.Sharma 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期649-654,共6页
We have studied the effects of the finite range on the fusion and/or breakup of ^6He^+238U and ^11Li+^208pb Pb dynamic polarization potential approach. It has been found of the interaction between the fragments of t... We have studied the effects of the finite range on the fusion and/or breakup of ^6He^+238U and ^11Li+^208pb Pb dynamic polarization potential approach. It has been found of the interaction between the fragments of the projectile systems at near barrier energies within the framework of that at near barrier energies the maximum flux is lost to the breakup channel and at energies well above the Coulomb barrier the fusion coupled with the breakup channel opens up, initially with sharp rise and later becoming saturated at energy nearly twice of the Coulomb barrier. Further, it is found that the breakup cross section increases with the increasing range of the interaction between the fragments of the projectile while the fusion coupled with the breakup channel cross section decreases with the increasing range. 展开更多
关键词 FUSION BREAKUP polarization potential and weakly bound nuclei
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New Agegraphic Dark Energy in Brans-Dicke Theory 被引量:1
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作者 LIU Xiang-Lai ZHANG Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期761-768,共8页
In this paper, we investigate the new agegraphic dark energy model in the framework of Brans-Dicke theory, which is a natural extension of the Einstein's general relativity. In this framework the form of the new ageg... In this paper, we investigate the new agegraphic dark energy model in the framework of Brans-Dicke theory, which is a natural extension of the Einstein's general relativity. In this framework the form of the new agegraphic dark energy density takes as pq = 3n^2Ф(t)η^-2, where η is the conformal age of the universe and Ф(t) is the Brans-Dicke scalar field representing the inverse of the time-variable Newton's constant. We derive the equation of state of the new agegraphic dark energy and the deceleration parameter of the universe in the Brans-Dicke theory. It is very interesting to find that in the Brans-Dicke theory the agegraphic dark energy realizes quintom-like behavior, i.e., its equation of state crosses the phantom divide ω= -1 during the evolution. We also compare the situation of the agegraphic dark energy model in the Brans-Dicke theory with that in the Einstein's theory. In addition, we discuss the new agegraphic dark energy model with interaction in the framework of the Brans-Dicke theory. 展开更多
关键词 agegraphic dark energy quantum gravity cosmic acceleration Brans--Dicke theory
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Volumetric fraction measurement in oil-water-gas multiphase flow with dual energy gamma-ray system 被引量:3
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作者 李东晖 吴应湘 +1 位作者 李志彪 钟兴福 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第12期1405-1411,共7页
Volumetric fraction distribution measurement is a constituent part of process tomography system in oil-water-gas multiphase flow. With the technological development of nuclear radial inspection, dual-energy γ-ray tec... Volumetric fraction distribution measurement is a constituent part of process tomography system in oil-water-gas multiphase flow. With the technological development of nuclear radial inspection, dual-energy γ-ray techniques make it possible to investigate the concentration of the different components on the cross-section of oil-water-gas multiphase pipe-flow. The dual-energy gamma-ray technique is based on materials attenuation coefficients measurement comprised of two radioactive isotopes of 241Am and 241Cs which have emission energies at 59.5 keV and 662 keV in this project. Nuclear instruments and data acquisition system were designed to measure the material’s attenuation dose rate and a number of static tests were conducted at the Multiphase Laboratory, Institute of Mechanics, Chinese Academy of Sciences. Three phases of oil-water-gas media were inves- tigated for their possible use to simulate different media volumetric fraction distributions in experimental vessels. Attenuation intensities were measured, and the arithmetic of linear attenuation coefficients and the equations of volumetric fractions were studied. Investigation of an unexpected measurement error from attenuation equations revealed that a modified arithmetic was involved and finally the system achieved acceptable accuracy in experimental research. 展开更多
关键词 Volumetric fraction Multiphase flow Dual-energy γ-ray Process tomography
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Ground-State and Thermal Entanglement in Three-Spin Heisenberg-XXZ Chain with Three-Spin Interaction 被引量:4
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作者 ZHANG Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期249-254,共6页
The entanglement properties of a three-spin X X Z Heisenberg chain with three-spin interaction are studied by means of concurrence of pairwise entanglement. We show that ground-state pairwise entanglement, pairwise th... The entanglement properties of a three-spin X X Z Heisenberg chain with three-spin interaction are studied by means of concurrence of pairwise entanglement. We show that ground-state pairwise entanglement, pairwise thermal entanglement, or quantum phase transition is not present in antiferromagnetic spin chain. For the ferromagnetic case, quantum phase transition takes place at A = 1 for anisotropic interaction and at some values of three-spin coupling strength, and pairwise thermal entanglement increases when the value of J/T increases and with anisotropic interaction and three-spin interaction decrease. In addition, we find that increasing the anisotropic interaction and the three-spin interaction will decrease critical temperature. 展开更多
关键词 xspin chain thermal entanglement quantum phase transition
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An Interacting Two-Fluid Scenario for Quintom Dark Energy 被引量:2
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作者 ZHANG Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期762-768,共7页
The Quintom dark energy is a proposal that explains the recent observations that mildly favor the equation of state of dark energy ω crossing -1 near the past. The Quintom model is often constructed by two scalar fie... The Quintom dark energy is a proposal that explains the recent observations that mildly favor the equation of state of dark energy ω crossing -1 near the past. The Quintom model is often constructed by two scalar fields, where one is the quintessence feld and another is the phantom field. The cosmological implication of the coupling of the two fields of the dark energy is out of question worth investigating. However, the consideration of the coupling in the field scenario is somewhat complex thus we propose an interacting two-fluid Quintom scenario for simplicity. The interaction between the two components is parametrized by a constant 71 in this scenario. The cosmological implications of this parametrization are investigated in detail in this paper. Also, a diagnostic for this model is performed by using the statefinder pairs {s, r} and {q, r}. 展开更多
关键词 Quintom dark energy interacting two-fluid scenario statefinder diagnostic
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