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2×5×5纯态量子体系完全纠缠态的分类 被引量:1
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作者 程硕 李军利 乔从丰 《中国科学院研究生院学报》 CAS CSCD 北大核心 2009年第3期303-309,共7页
基于"随机局域操作和经典通讯"对2×5×5纯态量子系统的完全纠缠态进行了分类,共得到34个不等价类.其中有3个类对应的纠缠态含有连续参数.对含参数类的参数进行了详细研究,发现其中有2个类只含1个独立参数;另外1个含... 基于"随机局域操作和经典通讯"对2×5×5纯态量子系统的完全纠缠态进行了分类,共得到34个不等价类.其中有3个类对应的纠缠态含有连续参数.对含参数类的参数进行了详细研究,发现其中有2个类只含1个独立参数;另外1个含有2个独立参数.而且这些独立参数并不完全任意,它们有确定的对称性.对于1个独立参数情形,得到该参数具有D3群对称性. 展开更多
关键词 量子纠缠 分类 多体
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A Study of One S- and One P-Wave Heavy Meson Interaction in a Chiral Quark Model 被引量:1
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作者 李明涛 王文玲 +1 位作者 董宇兵 张宗烨 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第1期63-70,共8页
The analytical forms of the interaction potentials between one pseudo-scalar/vector and one scalar/tensor/axial-vector heavy mesons are deduced based on a chiral quark model. Our results explicitly show the attractive... The analytical forms of the interaction potentials between one pseudo-scalar/vector and one scalar/tensor/axial-vector heavy mesons are deduced based on a chiral quark model. Our results explicitly show the attractive property between the two heavy mesons. Consequently, a series of possible molecular states are obtained. It is expected that our study might shed some light on the popular discussions of the newly observed XYZ states. 展开更多
关键词 P-WAVE chiral quark model new resonances
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Effect of Vibration on Water Transport through Carbon Nanotubes 被引量:1
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作者 陆杭军 弓晓晶 +2 位作者 王春雷 方海平 万荣正 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第3期1145-1148,共4页
We study the response of water permeation properties through a carbon nanotube on the time-dependent mechanical signals. It is found that there is a critical frequency of vibrating fc (about 1333 GHz) which plays a ... We study the response of water permeation properties through a carbon nanotube on the time-dependent mechanical signals. It is found that there is a critical frequency of vibrating fc (about 1333 GHz) which plays a significant role in the water permeation properties. The total water flow, the net flux, the number of hydrogen bonds and the dipole flipping frequency of the single-file water chain inside the nanotube are almost unchanged for the frequency of vibrating f 〈 fc. Simulation results show that the nanotube can be effectively resistant to the mechanical noise. Such excellent effect of noise screening is attributed to the exceptional property of water molecules connected by strong hydrogen bonds with each other and forming a one-dimensional water chain inside the nanotube. Our findings are important for the understanding of why biological systems can achieve accurate information transfer in an environment full of fluctuations. 展开更多
关键词 MOLECULAR-DYNAMICS CONDUCTION CHANNEL
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A Discussion of Deuteron Transverse Charge Densities
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作者 梁翠英 董宇兵 梁伟红 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第9期383-387,共5页
The deuteron transverse charge density ρC(b) is the two-dimensional Fourier transform of its charge form factor in the impact space. We show that different parameterizations of the charge form factors provide differe... The deuteron transverse charge density ρC(b) is the two-dimensional Fourier transform of its charge form factor in the impact space. We show that different parameterizations of the charge form factors provide different ρC(b),in particular at the central value of impact parameter(b = 0), although all the parameterizations can well reproduce the form factors in the region of small Q2. In addition, we also check the explicit contributions from the different coordinate intervals of the deuteron wave function to its root-mean-square radius. 展开更多
关键词 DEUTERON ELECTROMAGNETIC FORM factors TRANSVERSE CHARGE density root-mean-square
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Water and Ion Permeation through Electrically Charged Nanopore
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作者 曾立 左光宏 +4 位作者 弓晓晶 陆杭军 王春雷 吴可非 万荣正 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第4期1486-1489,共4页
The behaviour of water and small solutes in confined geometries is important to a variety of chemical and nanofluidic applications. Here we investigate the permeation and distribution of water and ions in electrically... The behaviour of water and small solutes in confined geometries is important to a variety of chemical and nanofluidic applications. Here we investigate the permeation and distribution of water and ions in electrically charged carbon cylindrical nanopore during the osmotic process using molecular dynamics simulations. In the simulations, charges are distributed uniformly on the pores with diameter of 0.9 nm. For nanopores with no charge or a low charge, ions are difficult to enter. With the increasing of charge densities on the pores, ions will appear inside the nanopores because of the large electronic forces between the ions and the charged pores. Different ion entries induce varying effects on osmotic water flow. Our simulations reveal that the osmotic water can flow through the negatively charged pore occupied by K^+ ions, while water flux through the positively charged pores will be disrupted by Cl^- ions inside the pores. This may be explained by the different radial distributions of K^+ ions and Cl^- ions inside the charged nanopores. 展开更多
关键词 MOLECULAR-DYNAMICS SIMULATIONS CARBON NANOTUBE MEMBRANES ELECTROOSMOTIC FLOW TRANSPORT CHANNEL MECHANISM SURFACE
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Gating of Water Flow Induced by Bending of a Carbon Nanotube 被引量:1
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作者 王棽 陆杭军 +2 位作者 涂育松 王春雷 方海平 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第6期291-293,共3页
The ON-OFF state transition of the water transport induced by the structural bending of a carbon nanotube is studied by molecule dynamics simulation. The water permeation through a bent carbon nanotube shows excellent... The ON-OFF state transition of the water transport induced by the structural bending of a carbon nanotube is studied by molecule dynamics simulation. The water permeation through a bent carbon nanotube shows excellent gating property with a threshold bending angle of about 14.6°. We also investigate the water density distribution inside the nanochannel to illustrate the mechanism. 展开更多
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A Quasi-One-Dimensional Model for a Chain of Water Molecules on the Nanometer Scale
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作者 吴可非 万荣正 +2 位作者 王春雷 任秀平 方海平 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第3期192-195,共4页
Water confined into the interior channels of narrow carbon nanotubes or transmembrane proteins can form collectively oriented molecular chains held together by tight hydrogen bonds. We develop a quasi-one-dimensional ... Water confined into the interior channels of narrow carbon nanotubes or transmembrane proteins can form collectively oriented molecular chains held together by tight hydrogen bonds. We develop a quasi-one-dimensional model for a chain of water molecules which interact with each other via the Coulomb and power-like repulsive interactions. We explore the equilibrium property of the water chain and derive an exact analytical expression for the total interaction energy of the water chain, denoted by W(0)int. It is found that W(0)int is minimal when the distance between the two neighboring water molecules in a hydrogen-bonded chain is equal to 0.265 nm. The model is expected to be useful for studying analytically the properties of single-file water molecules inside water channels, such as the concerted motion of water molecules. 展开更多
关键词 Soft matter liquids and polymers Atomic and molecular physics Biological physics
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Dynamic Effect of Rolling Massage on Blood Flow
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作者 CHEN Yan-Yan YI Hou-Hui +1 位作者 LI Hua-Bing FANG Hai-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期331-334,共4页
The Chinese traditional medical massage has been used as a natural therapy to eliminate some diseases. Here, the effect of the rolling massage frequency to the blood flow in the blood vessels under the rolling massage... The Chinese traditional medical massage has been used as a natural therapy to eliminate some diseases. Here, the effect of the rolling massage frequency to the blood flow in the blood vessels under the rolling massage manipulation is studied by the lattice Boltzmann simulation. The simulation results show that when the frequency is smaller than or comparable to the pulsatile frequency of the blood flow, the effect on the blood flux by the rolling massage is small. 011 the contrast, if the frequency is twice or more times of the pulsatile frequency of the blood flow, the blood flux is greatly enhanced and increases linearly with respect to the frequency. Similar behavior has also been observed on the shear stress on the blood vessel walls. The result is helpful for understanding that the rolling massage has the function of promoting the blood circulation and removing the blood stasis. 展开更多
关键词 rolling manipulation moving stenosed vessel wall shear stress LBM
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Effect of Center-of-Mass Motion Removal in the Molecular Dynamics Simulations
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作者 万荣正 李松焱 方海平 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第8期114-116,共3页
Molecule dynamics simulation is now widely used in the study of nano pores, proteins and nano-scale devices. The limited friction in such a system requires the method of center-of-mass motion removal to be applied. We... Molecule dynamics simulation is now widely used in the study of nano pores, proteins and nano-scale devices. The limited friction in such a system requires the method of center-of-mass motion removal to be applied. We test the effect of different time period T of this method under osmotic pressure difference, and find that the impact on the net flux is very small together with the effective reduction of the accumulated numerical error when the period T is above 0.1 ps. The simulation results also show that the change of this time period of method has very little effect on the potential of mean force of the water inside the carbon nanotubes. 展开更多
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Water Transport through Multinanopores Membranes
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作者 曾立 郭宏凯 +2 位作者 左光宏 万荣正 方海平 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第3期302-305,共4页
We investigate the influence of correlation between water molecules transport through the neighbouring nanopores, whose centres are at a distance of only 6.2A, using the molecular dynamics simulations. Water molecule ... We investigate the influence of correlation between water molecules transport through the neighbouring nanopores, whose centres are at a distance of only 6.2A, using the molecular dynamics simulations. Water molecule distribution in nanopore and average water flow are obtained. It is found that the average water molecule number and water flow are slightly different between a system made of the neighbouring nanopores and a system of a single pore. This indicates that transport of water chains in neighbouring pores do no show significant influence each other. These findings should be helpful in designing efficient artificial membrane made of nanopores and providing an insight into effects of the biological channel structure on the water permeation. 展开更多
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The parametric symmetry and numbers of the entangled class of 2×M×N system 被引量:2
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作者 LI XiKun LI JunLi +1 位作者 LIU Bin QIAO CongFeng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第8期1471-1475,共5页
We present in the work two intriguing results in the entanglement classification of a pure and true tripartite entangled state of 2 × M × N under stochastic local operation and classical communication: (i) t... We present in the work two intriguing results in the entanglement classification of a pure and true tripartite entangled state of 2 × M × N under stochastic local operation and classical communication: (i) the internal symmetric properties of the nonlocal parameters in the continuous entangled class; (ii) the analytic expression for the total numbers of the true and pure entangled class 2 × M × N states. These properties help better understand the nature of the 2 × M × N entangled system. 展开更多
关键词 ENTANGLEMENT quantum information matrix theory
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Deuteron electromagnetic form factors in transverse plane with a phenomenological Lagrangian approach 被引量:1
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作者 梁翠英 董宇兵 梁伟红 《Chinese Physics C》 SCIE CAS CSCD 2014年第7期50-58,共9页
A phenomenological Lagrangian approach is employed to study the electromagnetic properties of deuteron The deuteron is regarded as a loosely bound state of a proton and a neutron. The deuteron electromagnetic form fac... A phenomenological Lagrangian approach is employed to study the electromagnetic properties of deuteron The deuteron is regarded as a loosely bound state of a proton and a neutron. The deuteron electromagnetic form factors are expressed in light-front representation in the transverse plane. The transverse charge density of the deuteron is discussed. 展开更多
关键词 DEUTERON NUCLEON electromagnetic form factors transverse plane impact parameter space
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Λc重子谱疑难(英文)
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作者 吕齐放 董宇兵 +1 位作者 刘翔 MATSUKI Takayuki 《原子核物理评论》 CAS CSCD 北大核心 2018年第1期1-4,共4页
Λ_c+重子家族存在一个疑难,也就是重夸克有效理论预言的轨道角动量为L=2的多重态中的态在实验上是缺失的,而且已发现的Λ_c(2765)+和Λ_c(2940)+的JP量子数仍然未知。在本工作中,我们使用双夸克图像计算了重子的质量,研究了Λ_c(2765)... Λ_c+重子家族存在一个疑难,也就是重夸克有效理论预言的轨道角动量为L=2的多重态中的态在实验上是缺失的,而且已发现的Λ_c(2765)+和Λ_c(2940)+的JP量子数仍然未知。在本工作中,我们使用双夸克图像计算了重子的质量,研究了Λ_c(2765)+和Λ_c(2940)+的可能归类以及仍缺失的具有L=2和量子数的Λ_c+态,进而指出Λ_c(2880)+的峰结构中实际上已经包含了L=2、这一缺失态,并建议Λ_c(2765)+和Λ_c(2940)+的量子数应分别为2S(1/2+)和2P(1/2-)。 展开更多
关键词 Λc家族 相对论夸克模型 对夸克
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Constituent counting rule and the production of d~*(2380) at high energies
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作者 Yubing Dong Pengnian Shen 《Chinese Physics C》 SCIE CAS CSCD 2019年第5期41-46,共6页
The constituent counting rule, determining the scaling behavior of the transition amplitudes in an exclusive process at high energies, is applied to probe the internal structure of the newly observed d*(2380) resonanc... The constituent counting rule, determining the scaling behavior of the transition amplitudes in an exclusive process at high energies, is applied to probe the internal structure of the newly observed d*(2380) resonance. Several selected exclusive processes at high energies for the production of d* are discussed. Results of two structural scenarios for d*(2380), a hexaquark dominant compact system in the quark degrees of freedom, and a threebody bound state in the hadronic degrees of freedom, are analyzed and compared. A rather remarkable difference between the results of these two scenarios for the mentioned processes are addressed. 展开更多
关键词 CONSTITUENT chiral QUARK model d^*(2380) CONSTITUENT COUNTING RULE EXCLUSIVE process
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Holographic models of the scalar sector of QCD
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作者 Frédéric Jugeau 《Chinese Physics C》 SCIE CAS CSCD 2010年第9期1516-1519,共4页
We investigate the AdS/QCD duality for the two-point correlation functions of the lowest dimension scalar meson and scalar glueball operators,in the case of the Soft Wall holographic model of QCD.Masses and decay cons... We investigate the AdS/QCD duality for the two-point correlation functions of the lowest dimension scalar meson and scalar glueball operators,in the case of the Soft Wall holographic model of QCD.Masses and decay constants as well as gluon condensates are compared to their QCD estimates.In particular,the role of the boundary conditions for the bulk-to-boundary propagators is emphasized. 展开更多
关键词 AdS/QCD correspondence holographic models of QCD hadron spectroscopy
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DJpsiFDC:an event generator for the process gg→J/ψJ/ψ at the LHC
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作者 乔从丰 王健 郑阳恒 《Chinese Physics C》 SCIE CAS CSCD 2011年第3期209-213,共5页
DJpsiFDC is an event generator package for the process gg → J/ψJ/ψ. It generates events for primary leading-order 2 → 2 processes. The package could generate a Les Houches Event (LHE) document and this could eas... DJpsiFDC is an event generator package for the process gg → J/ψJ/ψ. It generates events for primary leading-order 2 → 2 processes. The package could generate a Les Houches Event (LHE) document and this could easily be embedded into detector simulation software frameworks. The package is produced in Fortran code. 展开更多
关键词 event generator FDC J/ψ pair color-octet
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Pion charge form factor and constraints from space-time translations
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作者 B.Desplanques 董宇兵 《Chinese Physics C》 SCIE CAS CSCD 2010年第9期1342-1345,共4页
The role of Poincaré covariant space-time translations is investigated in the case of a relativistic quantum mechanics approach to the pion charge form factor.It is shown that the related constraints are generall... The role of Poincaré covariant space-time translations is investigated in the case of a relativistic quantum mechanics approach to the pion charge form factor.It is shown that the related constraints are generally inconsistent with the assumption of a single-particle current,which is most often referred to.The only exception is the front-form approach with q ^+ = 0.How accounting for the related constraints,as well as restoring the equivalence of different RQM approaches in estimating form factors,is discussed.Some extensions of this work and,in particular,the relationship with a dispersion-relation approach,are presented.Conclusions relative to the underlying dynamics are given. 展开更多
关键词 form factors PION relativisty COVARIANCE TRANSLATIONS
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J^P assignments of Λ_c^+ baryons
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作者 陈兵 王登霞 张爱林 《Chinese Physics C》 SCIE CAS CSCD 2009年第12期1327-1330,共4页
The "good" diquark is employed to study A+ baryons within a mass loaded flux tube model. The study indicates that all A+ baryons candidates in the 2008 review by the Particle Data Group (PDG) are well described ... The "good" diquark is employed to study A+ baryons within a mass loaded flux tube model. The study indicates that all A+ baryons candidates in the 2008 review by the Particle Data Group (PDG) are well described in the mass loaded flux model. The quantum numbers JP of these A+ candidates are assigned. If Ac(2765)+ is an orbitally excited A+, it is likely the JP=3/2+one. If ∧c(2765)+ is an orbitally excited ∑c, there ought to be another JP=3/2+∧c+with mass ≈2770 MeV. In the model, there exists no JP=1/2+∧c+(≈2700)predicted in existing literature. Ac (2940)+ is very possible the orbitally excited baryon with 展开更多
关键词 DIQUARK flux tube model charmed baryons
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A study of transverse charge density of pions in relativistic quantum mechanics
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作者 董宇兵 王翼展 《Chinese Physics C》 SCIE CAS CSCD 2011年第8期713-716,共4页
The transverse charge density of pions is calculated based on relativistic quantum mechanics, where the pion is regarded as a quark-antiquark bound state. Corrections from the two spin-1/2 constituents and from the wa... The transverse charge density of pions is calculated based on relativistic quantum mechanics, where the pion is regarded as a quark-antiquark bound state. Corrections from the two spin-1/2 constituents and from the wave function of a quark and antiquark inside the bound system are discussed. The calculated results are compared to the results with a realistic effective Lagrangian approach as well as to that with a simple covariant model where the pion is regarded as a composite system with two scalar particles. 展开更多
关键词 transverse charge density PION compositeness condition relativistic quantum mechanics
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A study of meson-meson potential in the chiral quark model
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作者 李明涛 董宇兵 张宗烨 《Chinese Physics C》 SCIE CAS CSCD 2011年第7期622-628,共7页
An effective potential in a meson-meson system is discussed based on the SU(3) chiral constituent quark model, and the analytic form of the potential is explicitly given. In addition, the effective potential is empl... An effective potential in a meson-meson system is discussed based on the SU(3) chiral constituent quark model, and the analytic form of the potential is explicitly given. In addition, the effective potential is employed to study the bound state problem of ωφ, which is related to the new resonance of f0(1810) observed in BES Ⅱ very recently. 展开更多
关键词 cluster model SU(3) chiral quark model molecule states meson-meson effective potential
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