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
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
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
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
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
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
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
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
The effect of the two-photon exchange on the deuteron electromagnetic form factors is estimated based on an effective Lagrangian approach. A numerical estimate calculation of the effect is discussed. In particular, th...The effect of the two-photon exchange on the deuteron electromagnetic form factors is estimated based on an effective Lagrangian approach. A numerical estimate calculation of the effect is discussed. In particular, the effect on the polarization observables is analyzed.展开更多
The electromagnetic form factors and low-energy observables of the deuteron are studied with the help of the light-front approach, where the deuteron is regarded as a weakly bound state of a proton and a neutron. Both...The electromagnetic form factors and low-energy observables of the deuteron are studied with the help of the light-front approach, where the deuteron is regarded as a weakly bound state of a proton and a neutron. Both the S and D wave interacting vertexes among the deuteron, proton, and neutron are taken into account. Moreover,the regularization functions are also introduced. In our calculations, the vertex and the regularization functions are employed to simulate the momentum distribution inside the deuteron. Our numerical results show that the lightfront approach can roughly reproduce the deuteron electromagnetic form factors, like charge G0, magnetic G1, and quadrupole G2, in the low Q~2 region. The important effect of the D wave vertex on G2is also addressed.展开更多
Dirac and Pauli form factors are investigated in the relativistic chiral effective Lagrangian.The octet and decuplet intermediate states are included in the one-loop calculation.The 4-dimensional regulator is introduc...Dirac and Pauli form factors are investigated in the relativistic chiral effective Lagrangian.The octet and decuplet intermediate states are included in the one-loop calculation.The 4-dimensional regulator is introduced to deal with the divergence.Different from the non-relativistic case,this 4-dimensional regulator is generated from the nonlocal Lagrangian with the gauge link,which guarantees local gauge invariance.As a result,additional diagrams appear which ensure electric charge 1 and 0 for proton and neutron respectively.The obtained Dirac and Pauli form factors of the nucleons are all reasonable up to relatively large Q;.展开更多
The electromagnetic form factors of the deuteron, particularly its quadrupole form factor, are studied with the help of a phenomenological Lagrangian approach where the vertex of the deuteron proton-neutron with D-sta...The electromagnetic form factors of the deuteron, particularly its quadrupole form factor, are studied with the help of a phenomenological Lagrangian approach where the vertex of the deuteron proton-neutron with D-state contribution is explicitly taken into account. The results show the importance of this contribution to the deuteron quadrupole form factor in the approach.展开更多
We adopt the quark pair creation model to investigate the light meson emissions of several charmoniumlike states.The quark pair creation model is applied to four-body systems,and we calculate the pion/kaon emissions o...We adopt the quark pair creation model to investigate the light meson emissions of several charmoniumlike states.The quark pair creation model is applied to four-body systems,and we calculate the pion/kaon emissions of X(4700),Z_(c)(4430),Y(4230),Y(4360),Y(4390),and Y(4660)within compact tetraquark configurations.We find that the pion/kaon decay widths of X(4700)and Z_(c)(4430)the resonances Y(4230),Y(4360),Y(4390),and Y(4660)cay behaviors will provide useful information for future experimental searches and theoretical interpretations.展开更多
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
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
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
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
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
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
基金Supported by the National Natural Science Foundation of China under Grant Nos 10604060, 10674146 and 10825520, the National Basic Research Program of China under Grant No 2007CB36000, and the Shanghai Supercomputer Center of China.
文摘分子动力学模拟现在广泛地在 nano 毛孔,蛋白质和 nano 规模设备的学习被使用。在如此的一个系统的有限磨擦要求要使用的 center-of-mass 运动移动的方法。我们在渗透的压力差别下面测试这个方法的不同时间时期 T 的效果,并且当时期 T 在 0.1 ps 上面时,发现网流动上的影响和积累的数字错误的有效减小是很小的。模拟结果也证明变化这次,方法的时期在碳 nanotubes 内在水的吝啬的力量的潜力上有很小的效果。[从作者抽象]
基金Supported by the National Natural Science Foundation of China under Grant No 10604060, and the Shanghai Supercomputer Center of China.
文摘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.
基金Supported by Chinese Academy of Sciences, the National Natural Science Foundation of China under Grant Nos 10604060 and 10674146, and Shanghai Supercomputer Center. We thank Professor Haiping FANG for the suggestion of the project and helpful discussion.
文摘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.
基金Supported by Chinese Academy of Sciences, the National Natural Science Foundation of China under Grant Nos 10674146 and 10825520, the National Basic Research Program of China under Grant No 2007CB936000, and Shanghai Supercomputer Center.
文摘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.
基金Supported by the National Natural Science Foundation of China under Grants Nos 10604060 and 10674146. To whom correspondence should be addressed. We thank Jingyuan Li, Songyan Li and Xiaoyan Zhou for helpful discussion and suggestions. This research is assisted by the Shanghai Supercomputer Center of China.
文摘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.
基金Supported by Chinese Academy of Sciences, the National Natural Science Foundation of China under Grant Nos 10674146, 10604060 and 10825520, and Shanghai Supercomputer Center of China.We thank Professor Hu Jun for the suggestion of this work, and Wang Chunlei and Xiu Peng for helpful discussion and comments.
文摘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.
基金Supported by National Natural Science Foundation of China(10975146,11035006,11261130,11165005)DFGthe NSFC through funds provided to the Sino-Germen CRC 110"Symmetries and the Emergence of Structure in QCD"
文摘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.
基金partly supported by the National Sciences Foundations of China under grants No.10775148,10975146 (Y.B.)grateful to the CAS for grant No KJCX3-SYW-N2
文摘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.
基金Supported by National Natural Science Foundation of China (10935012, 10928510, 10821063, 10775179)CAS Key Projects(KJCX2-yw-N29, H92A0200S2)100 Talents Program of CAS
文摘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.
基金Supported by National Natural Science Foundation of China (10775148,10975146)
文摘The effect of the two-photon exchange on the deuteron electromagnetic form factors is estimated based on an effective Lagrangian approach. A numerical estimate calculation of the effect is discussed. In particular, the effect on the polarization observables is analyzed.
基金Supported by National Natural Science Foundation of China(10975146,11475192)The fund provided by the Sino-German CRC110 “Symmetries and the Emergence of Structure in QCD”FAPESP grant 2011/11973-4 for funding his visit to ICTP-SAIFR
文摘The electromagnetic form factors and low-energy observables of the deuteron are studied with the help of the light-front approach, where the deuteron is regarded as a weakly bound state of a proton and a neutron. Both the S and D wave interacting vertexes among the deuteron, proton, and neutron are taken into account. Moreover,the regularization functions are also introduced. In our calculations, the vertex and the regularization functions are employed to simulate the momentum distribution inside the deuteron. Our numerical results show that the lightfront approach can roughly reproduce the deuteron electromagnetic form factors, like charge G0, magnetic G1, and quadrupole G2, in the low Q~2 region. The important effect of the D wave vertex on G2is also addressed.
基金Supported by National Natural Science Foundation of China(11475186)Sino-German CRC 110(NSFC 11621131001)
文摘Dirac and Pauli form factors are investigated in the relativistic chiral effective Lagrangian.The octet and decuplet intermediate states are included in the one-loop calculation.The 4-dimensional regulator is introduced to deal with the divergence.Different from the non-relativistic case,this 4-dimensional regulator is generated from the nonlocal Lagrangian with the gauge link,which guarantees local gauge invariance.As a result,additional diagrams appear which ensure electric charge 1 and 0 for proton and neutron respectively.The obtained Dirac and Pauli form factors of the nucleons are all reasonable up to relatively large Q;.
基金Supported by NSFC(11475192,10975146,11035006,10775148)
文摘The electromagnetic form factors of the deuteron, particularly its quadrupole form factor, are studied with the help of a phenomenological Lagrangian approach where the vertex of the deuteron proton-neutron with D-state contribution is explicitly taken into account. The results show the importance of this contribution to the deuteron quadrupole form factor in the approach.
基金Supported by the National Natural Science Foundation of China(11705056,12175037,11947224,11475192,11975245,U1832173)the Key Project of Hunan Provincial Education Department under(21A0039)+3 种基金the State Scholarship Fund of China Scholarship Council(22006725011)the Sino-German CRC 110“Symmetries and the Emergence of Structure in QCD”project by NSFC(12070131001)the Key Research Program of Frontier Sciences,CAS(Y7292610K1)the National Key Research and Development Program of China(2020YFA0406300)。
文摘We adopt the quark pair creation model to investigate the light meson emissions of several charmoniumlike states.The quark pair creation model is applied to four-body systems,and we calculate the pion/kaon emissions of X(4700),Z_(c)(4430),Y(4230),Y(4360),Y(4390),and Y(4660)within compact tetraquark configurations.We find that the pion/kaon decay widths of X(4700)and Z_(c)(4430)the resonances Y(4230),Y(4360),Y(4390),and Y(4660)cay behaviors will provide useful information for future experimental searches and theoretical interpretations.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10935012, 10928510, 10821063 and 10775179)the Chinese Academy of Sciences Key Projects (Grant Nos. KJCX2-yw-N29 andH92A0200S2)the Scientific Research Fund of Graduate University, the Chinese Academy of Sciences
文摘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.
基金Supported by National Natural Science Foundation of China under Grant Nos.11105158,11035006,10975146,11261130,and 11475192Ministry of Science and Technology of China under Grant No.2009CB825200+1 种基金the Fundamental Research Funds for the Central Universities of Chinathe DFG and NSFC through Funds Provides to the Sino–German CRC 110"Symmetries and the Emergence of Structure in QCD"
文摘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.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10975146,11035006,11261130,and 11165005
文摘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.
基金Supported by the National Natural Sciences Foundations of China(11475192,11475181,11521505,11565007,11635009)the Sino-German CRC 110 "Symmetries and the Emergence of Structure in QCD" project by NSFC(11621131001)+1 种基金the Key Research Program of Frontier Sciences,CAS,(Y7292610K1)the IHEP Innovation Fund(Y4545190Y2)
文摘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.
基金Supported by National Natrual Science Foundation (10775146, 10775148, 10975146, 11035006)Ministry of Science and Technology of China (2009CB825200)
文摘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.
基金Supported by National Natural Science Foundation of China (10775148,10975146,11035006)
文摘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.