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Dialogue on Supranuclear Matter at the Dream Field:A Summary
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作者 ZHOU Enping JIANG Jinchen +4 位作者 LUO Yudong WANG Weiyang XIA Chengjun ZHANG Chen XU Renxin 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第6期1143-1156,共14页
Understanding the equation of state of cold dense matter,i.e.,those inside neutron stars,is a key problem in the multi-messenger astronomical era.In order to facilitate the scientific discussions between different com... Understanding the equation of state of cold dense matter,i.e.,those inside neutron stars,is a key problem in the multi-messenger astronomical era.In order to facilitate the scientific discussions between different commu-nities in the relevant fields,particularly between nuclear physicists and astrophysicists,we have organized the Dialo-gue at the Dream Field(DDF2024).The participants explored topics of various fields such as pulsar astrophysics,transient phenomena,hadronic and nuclear matter,supra-nuclear matter with quark degree of freedom,numerical relativity.This involved discussions on the mechanisms,model constructions,observational impacts,and introduc-tions of new facilities.In-depth exchanges were carried out through invited talks and free discussions,as well as a visit to view the FAST telescope. 展开更多
关键词 pulsar neutron star γ-ray burst fast radio burst dense matter numerical relativity
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柏拉图的自我批判 被引量:3
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作者 陆沉 《四川大学学报(哲学社会科学版)》 CSSCI 北大核心 2003年第4期56-62,共7页
《巴门尼德篇》是柏拉图(Platon)最重要的哲学著作之一,它主要由两个部分组成,第一部分是柏拉图对自己的以《斐多篇》—《国家篇》为代表的"相论"的错误的反思批判,在第二部分,柏拉图尝试重建"相论",结果是一个初... 《巴门尼德篇》是柏拉图(Platon)最重要的哲学著作之一,它主要由两个部分组成,第一部分是柏拉图对自己的以《斐多篇》—《国家篇》为代表的"相论"的错误的反思批判,在第二部分,柏拉图尝试重建"相论",结果是一个初步的范畴论②。 展开更多
关键词 柏拉图 “相” “相论” 范畴论 目的论 实体化
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Characterization of ST13 Protein Expression in Human Colorectal Cancer Tissues 被引量:4
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作者 郑树 邵吉民 +2 位作者 董琦 彭佳萍 张苏展 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期2-7,65,共7页
Objective: To characterize the expression of ST13 protein in human tissuesfor investigation of the function of colorectal cancer related gene ST13. Methods: ST13 ORF wascloned and over-expressed in E.coli. The recombi... Objective: To characterize the expression of ST13 protein in human tissuesfor investigation of the function of colorectal cancer related gene ST13. Methods: ST13 ORF wascloned and over-expressed in E.coli. The recombinant ST13 protein was purified by affinitychromatography. ST13 monoclonal antibodies were generated and affinity purified with the recombinantprotein. Immunoblot and immunohistochemical staining were employed to analyze ST13 proteinexpression in human tissues. Results: The expression and purification of the recombinant ST13protein were confirmed by SDS-PAGE. The protein yield reached about 2.5 mg/L of induced bacterialculture with a purity of 91.3%. Three strains of hybridoma were obtained with antibody titers from10~4 to 10~5 in ascites fluids and with high specificity for ST13 protein. Immunoblot showed thatthe apparent Mr of ST13 protein in SW480 cells and human tissues estimated by SDS-PAGE mobility wasapproximately 50 000, which was about 10 000 larger than the 41 324 calculated, but theglycosylation of the protein was excluded. Computer modeling revealed the protein to be ahydrophilic molecule. Immunohistochemical staining showed that ST13 protein was evenly distributedin cytoplasm and expressed in colon, stomach, liver, and other epithelial cells. Differences in thestaining intensity of the protein were observed between normal and cancer tissues as well as amongdifferent normal or carcinoma tissues. Conclusion: ST13 protein is a cytoplasmic molecule with anapparent Mr of 50 000. The protein is expressed in colorectal and other epithelial tissues. Theexpression level of the protein is down-regulated in colorectal cancer and varies among differentnormal and/or carcinoma tissues. Comparison of cDNA sequences and protein characteristics indicatesthat ST13 protein and hsp70-interacting protein (Hip) are same proteins, raising the possibilitythat ST13 protein is involved in the development of colorectal cancer through Hsp70 molecularchaperone machinery. 展开更多
关键词 colorectal cancer related gene ST13 prokaryotic expression monoclonalantibody preparation immunocytochemical staining western blot protein/characterization/expressionlevel
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Theoretical investigations on CO oxidation reaction catalyzed by gold nanoparticles 被引量:2
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作者 孙科举 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第10期1608-1618,共11页
It is crucial to understand the mechanism of low temperature CO oxidation reaction catalyzed by gold nanoparticles so as to find out the origin of the high catalytic reactivity and extend the indus‐trialization appli... It is crucial to understand the mechanism of low temperature CO oxidation reaction catalyzed by gold nanoparticles so as to find out the origin of the high catalytic reactivity and extend the indus‐trialization applications of nano gold catalysts. In this work, some theoretical works on CO adsorp‐tion, O2 adsorption, atomic oxygen adsorption, formation of surface gold oxide films, reaction mechanisms of CO oxidation involving O2 reaction with CO and O2 dissociation before reacting with CO on gold surfaces and Au/metal oxide were summarized, and the influences of coordination number, charge transfer and relativity of gold on CO oxidation reaction were briefly reviewed. It was found that CO reaction mechanism depended on the systems with or without oxide and the strong relativistic effects might play an important role in CO oxidation reaction on gold catalysts. In particular, the relativistic effects are related to the unique behaviors of CO adsorption, O adsorption, O2 activation on gold surfaces, effects of coordination number and the wide gap between the chem‐ical inertness of bulk gold and high catalytic activity of nano gold. The present work helps us to understand the CO oxidation reaction mechanism on gold catalysts and the influence of relativistic effects on gold catalysis. 展开更多
关键词 Carbon monoxide oxidation reaction Gold nanoparticle Reaction mechanism Theoretical calculation Relativistic effect
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ESTIMATION METHOD FOR AIRCRAFT SIMILARITY BASED ON FUZZY THEORY AND GREY INCIDENCE ANALYSIS 被引量:4
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作者 李永平 陈闵叶 刘明 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期194-198,共5页
An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the... An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the method of grey incidence analysis. Nine feature attributes of aircraft are selected to estimate the similarity between the new aircraft and the existing aircraft. A new aircraft X and other six existing aircrafts are taken as examples. Analyses show that similarity estimation results obtained from the method are in accordance with practice. 展开更多
关键词 aircraft similarity fuzzy theory grey incidence analysis
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INTERNET TRAFFIC DATA FLOW FORECAST BY RBF NEURAL NETWORK BASED ON PHASE SPACE RECONSTRUCTION 被引量:4
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作者 陆锦军 王执铨 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期316-322,共7页
Characteristics of the Internet traffic data flow are studied based on the chaos theory. A phase space that is isometric with the network dynamic system is reconstructed by using the single variable time series of a n... Characteristics of the Internet traffic data flow are studied based on the chaos theory. A phase space that is isometric with the network dynamic system is reconstructed by using the single variable time series of a network flow. Some parameters, such as the correlative dimension and the Lyapunov exponent are calculated, and the chaos characteristic is proved to exist in Internet traffic data flows. A neural network model is construct- ed based on radial basis function (RBF) to forecast actual Internet traffic data flow. Simulation results show that, compared with other forecasts of the forward-feedback neural network, the forecast of the RBF neural network based on the chaos theory has faster learning capacity and higher forecasting accuracy. 展开更多
关键词 chaos theory phase space reeonstruction Lyapunov exponent tnternet data flow radial basis function neural network
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A Straightforward Method of Calculating Finely the Soft X-Ray Spectra of Hydrogenlike Highly Ionized-States
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作者 尹钊 张国营 张学龙 《Journal of Southeast University(English Edition)》 EI CAS 2001年第2期87-90,共4页
A new method of calculating finely the soft X ray spectra of hydrogenlike highly ionized states is presented. It is based on the relation of the ionicity and the ionization energies of hydrogenlike atoms and the new... A new method of calculating finely the soft X ray spectra of hydrogenlike highly ionized states is presented. It is based on the relation of the ionicity and the ionization energies of hydrogenlike atoms and the new model of potential function of hydrogenlike atoms. The relativistic revision and the spin orbit couping of excitation energy levels are taken into account. The calculated results are in good agreement with the experiments. 展开更多
关键词 hydrogenlike ions spectra of soft X ray effect of ionicity relativistic effect
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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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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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High Pressure Phase Stability of Ti with Self-consistent ab initio Lattice Dynamics Approach
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作者 曾召益 胡翠娥 +2 位作者 刘勋 张伟 蔡灵仓 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期168-172,I0001,共6页
The traditional quasiharmonic approximation cannot predict the phase diagram of Ti accu- rately, due to the well-known soften phonon modes of the β-Ti. By means of self-consistent ab initio lattice dynamics (SCAILD... The traditional quasiharmonic approximation cannot predict the phase diagram of Ti accu- rately, due to the well-known soften phonon modes of the β-Ti. By means of self-consistent ab initio lattice dynamics (SCAILD) method, in which the effects of phonon-phonon in- teractions are considered, the phonon dispersion relations at finite temperature for Ti are calculated. From the phonon dispersions, we extrapolat the acoustic velocities and harmonic elastic constants. The dynamical stable regions and phase diagram of Ti are also predicted successfully. The results show that SCAILD method can be designed to work for strongly anharmonic systems where the QHA fails. 展开更多
关键词 Transition metal Lattice dynmnics Phase transition Density functionaltheory
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Density Functional Study on Relative Energies, Structures, and Bonding ofLow-lying Electronic States of Lutetium Dimer
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作者 夏琼琼 肖伟 +2 位作者 章永凡 宁利新 崔执凤 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期371-379,447,共10页
Low-lying electronic states of the lutetium dimer (Lu2) were studied based on density functional theory (DFT) using ten different density functionals together with three different relativistic effective core pseud... Low-lying electronic states of the lutetium dimer (Lu2) were studied based on density functional theory (DFT) using ten different density functionals together with three different relativistic effective core pseudopotentials (RECPs). Relative state energies, equilibrium bond lengths, vibrational frequencies, and ground-state dissociation energies were evaluated. It was found that the ground state is a triplet state irrespective of the type of functional and RECP used. This result is in contrast with a previous DFT calculation which gave a singlet ground state for Lu2. By comparing with the high-level ab initio and available experimental results, it is evident that the hybrid-GGA functionals combined with the Stuttgart smallcore RECP yield the best overall agreement for the properties under study. The effects of Hartree-Fock exchange in B3LYP functional on the calculated bond length and dissociation energy of the ground state were examined, and rationalized in terms of 5d participation in Lu-Lu covalent bonding. 展开更多
关键词 Lutetium dimer Density functional theory Relativistic effective core pseudopotential Hartree-Fock exchange Covalent bonding
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Relativistic Calculations for Be-like Iron 被引量:4
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作者 YANG Jian-Hui LI Ping +1 位作者 ZHANG Jian-Ping LI Hui-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期468-472,共5页
Relativistic configuration interaction calculations for the states of 1s^22s^2, 1s^22s3l (l = s,p,d) and 1s^22p31 (l=s,p,d) configurations of iron are carried out using relativistic configuration interaction (RCI... Relativistic configuration interaction calculations for the states of 1s^22s^2, 1s^22s3l (l = s,p,d) and 1s^22p31 (l=s,p,d) configurations of iron are carried out using relativistic configuration interaction (RCI) and multi-configuration Dirac-Fock (MCDF) method in the active interaction approach. In the present calculation, a large-scale configuration expansion was used in describing the target states. These results are extensively compared with other available calculative and experimental and observed values, the corresponding present results are in good agreement with experimental and observed values, and some differences are found with other available calculative values. Because more relativistic effects are considered than before, the present results should be more accurate and reliable. 展开更多
关键词 TRANSITION Fe XXIII multi-configuration Dirac-Fock relativistic configuration interaction
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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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Mei Symmetry and Noether Symmetry of the Relativistic Variable Mass System 被引量:2
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作者 FANGJian-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期349-352,共4页
The definition and criterion of the Mei symmetry of a relativistic variable mass system are given. The relation between the Mei symmetry and the Noether symmetry of the system is found under infinitesimal transformati... The definition and criterion of the Mei symmetry of a relativistic variable mass system are given. The relation between the Mei symmetry and the Noether symmetry of the system is found under infinitesimal transformations of groups. The conserved quantities to which the Mei symmetry and Noether symmetry of the system lead are obtained.An example is given to illustrate the application of the result. 展开更多
关键词 RELATIVITY variable mass system Mei symmetry Noether symmetry conserved quantity relativistic variable mass system
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Integrating Factors and Conservation Laws for Relativistic Mechanical System 被引量:4
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作者 ZHANG Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期231-234,共4页
In this paper, we present a new method to construct the conservation laws for relativistic mechanical systems by finding corresponding integrating factors. First, the Lagrange equations of relativistic mechanical syst... In this paper, we present a new method to construct the conservation laws for relativistic mechanical systems by finding corresponding integrating factors. First, the Lagrange equations of relativistic mechanical systems are established, and the definition of integrating factors of the systems is given; second, the necessary conditions for the existence of conserved quantities of the relativistic mechanical systems are studied in detail, and the relation between the conservation laws and the integrating factors of the systems is obtained and the generalized Killing equations for the determination of the integrating factors are given; finally, the conservation theorem and its inverse for the systems are established, and an example is given to illustrate the application of the results. 展开更多
关键词 RELATIVITY mechanical system conservation law integrating factor Killing equation
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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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Routh Order Reduction Method of Relativistic Birkhoffian Systems 被引量:3
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作者 LUO Shao-Kai GUO Yong-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期209-212,共4页
Routh order reduction method of the relativistic Birkhoffian equations is studied. For a relativistic Birkhoffian system, the cyclic integrals can be found by using the perfect differential method. Through these cycli... Routh order reduction method of the relativistic Birkhoffian equations is studied. For a relativistic Birkhoffian system, the cyclic integrals can be found by using the perfect differential method. Through these cyclic integrals, the order of the system can be reduced. If the relativistic Birkhoffian system has a cyclic integral, then the Birkhoffian equations can be reduced at least by two degrees and the Birkhoffian form can be kept. The relations among the relativistic Birkhoffian mechanics, the relativistic Hamiltonian mechanics, and the relativistic Lagrangian mechanics are discussed, and the Routh order reduction method of the relativistic Lagrangian system is obtained. And an example is given to illustrate the application of the result. 展开更多
关键词 RELATIVITY Birkhoffian system Lagrangian system cyclic integral order reduction method
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Lie Symmetrical Perturbation and Adiabatic Invariants of Generalized Hojman Type for Relativistic Birkhoffian Systems 被引量:4
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作者 LUO Shao-Kai GUO Yong-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期25-30,共6页
For a relativistic Birkhoffian system, the Lie symmetrical perturbation and adiabatic invariants of generalized Bojman type are studied under general infinitesimal transformations. On the basis of the invariance of re... For a relativistic Birkhoffian system, the Lie symmetrical perturbation and adiabatic invariants of generalized Bojman type are studied under general infinitesimal transformations. On the basis of the invariance of relativistic Birkhotfian equations under general infinitesimal transformations,Lie symmetrical transformations of the system are constructed, which only depend on the Birkhoffian variables. The exact invariants in the form of generalized Hojman conserved quantities led by the Lie symmetries of relativistic Birkhoffian system without perturbations are given. Based on the definition of higher-order adiabatic invariants of a mechanical system, the perturbation of Lie symmetries for relativistic Birkhoffian system with the action of small disturbance is investigated, and a new type of adiabatic invariants of the system is obtained. In the end of the paper, an example is given to illustrate the application of the results. 展开更多
关键词 relativity BirkhofIian system Lie symmetrical perturbation exact invariant adiabatic invariant of generalized Hojman type
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Relativistic Consistent Angular-Momentum Projected Shell-Model: Relativistic Mean Field 被引量:3
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作者 LIYan-Song LONGGui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期429-434,共6页
We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method... We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method. In this new model, nuclear ground-state properties are first calculated consistently using relativistic mean-field (RMF) theory. Then angular momentum projection method is used to project out states with good angular momentum from a few important configurations. By diagonalizing the hamiltonian, the energy levels and wave functions are obtained. This model is a new attempt for the understanding of nuclear structure of normal nuclei and for the prediction of nuclear properties of nuclei far from stability. In this paper, we will describe the treatment of the relativistic mean field. A computer code, RECAPS-RMF, is developed. It solves the relativistic mean field with axial-symmetric deformation in the spherical harmonic oscillator basis. Comparisons between our calculations and existing relativistic mean-field calculations are made to test the model. These include the ground-state properties of spherical nuclei <SUP>16</SUP>O and <SUP>208</SUP>Pb, the deformed nucleus <SUP>20</SUP>Ne. Good agreement is obtained. 展开更多
关键词 relativistic consistent angular-momentum projected shell-model relativistic mean field projected shell model PECAPS-RMF
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Quantum Entropy of Black Hole with Internal Global Monopole 被引量:4
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作者 HANYi-Wen YANGShu-Zheng LIUWen-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期382-384,共3页
Using the generalized uncertainty relation, the new equation of state density is obtained, and then the entropy of black hole with an internal global monopole is discussed. The divergence that appears in black hole en... Using the generalized uncertainty relation, the new equation of state density is obtained, and then the entropy of black hole with an internal global monopole is discussed. The divergence that appears in black hole entropy calculation through original brick-wall model is overcome. The result of the direct proportion between black hole entropy and its event horizon area is drawn and given. The result shows that the black hole entropy must be the entropy of quantum state near the event horizon. 展开更多
关键词 generalized uncertainty relation state density quantum entropy black hole
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