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Natural gas hydrate shell model in gas-slurry pipeline flow 被引量:10
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作者 Jing Gong Bohui Shi Jiankui Zhao 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第3期261-266,共6页
A hydrate shell model coupled with one-dimensional two-fluid pipe flow model was established to study the flow characteristics of gas-hydrate slurry flow system.The hydrate shell model was developed with kinetic limit... A hydrate shell model coupled with one-dimensional two-fluid pipe flow model was established to study the flow characteristics of gas-hydrate slurry flow system.The hydrate shell model was developed with kinetic limitations and mass transfer limitations,and it was solved by Euler method.The analysis of influence factors was performed.It was found that the diffusion coefficient was a key parameter in hydrate forming process.Considering the hydrate kinetics model and the contacting area between gas and water,the hydrate shell model was more close to its practical situations. 展开更多
关键词 natural gas hydrate shell model gas-slurry pipeline flow
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Anomalous scaling in a non-Gaussian random shell model for passive scalars 被引量:1
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作者 赵英奎 陈式刚 王光瑞 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2848-2854,共7页
In this paper, we have introduced a shell-model of Kraichnan's passive scalar problem. Different from the original problem, the prescribed random velocity field is non-Gaussian and σ correlated in time, and its intr... In this paper, we have introduced a shell-model of Kraichnan's passive scalar problem. Different from the original problem, the prescribed random velocity field is non-Gaussian and σ correlated in time, and its introduction is inspired by She and Levveque (Phys. Rev. Lett. 72, 336 (1994)). For comparison, we also give the passive scalar advected by the Gaussian random velocity field. The anomalous scaling exponents H(p) of passive scalar advected by these two kinds of random velocities above are determined for structure function with values of p up to 15 by Monte Carlo simulations of the random shell model, with Gear methods used to solve the stochastic differential equations. We find that the H(p) advected by the non-Gaussian random velocity is not more anomalous than that advected by the Gaussian random velocity. Whether the advecting velocity is non-Gaussian or Gaussian, similar scaling exponents of passive scalar are obtained with the same molecular diffusivity. 展开更多
关键词 SCALING shell model She and Leveque (SL) model NON-GAUSSIAN passive scalar
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Elastic Constants of Superconducting MgB2 from Molecular Dynamics Simulations with Shell Model 被引量:1
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作者 GUO Yun-Dong CHEN Xiang-Rong +1 位作者 YANG Xiang-Dong GOU Qing-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期936-940,共5页
The elastic constants of superconducting MgB2 are calculated using a molecular dynamics method (MD)with shell model. The lattice parameters, five independent elastic constants, equations of state (EOS), Debye temperat... The elastic constants of superconducting MgB2 are calculated using a molecular dynamics method (MD)with shell model. The lattice parameters, five independent elastic constants, equations of state (EOS), Debye temperature, and bulk modulus of MgB2 are obtained. Meanwhile, the dependence of the bulk modulus B, the lattice parameters a and c, and the unit cell volume V on the applied pressure are presented. It is demonstrated that the method introduced here can well reproduce the experimental results with a reasonable accuracy. 展开更多
关键词 MGB2 elastic constants shell model molecular dynamics
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Nucleon—Pair Shell Model:Magnetic Excitations for Ba Isotopes 被引量:1
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作者 LUOYan-An NINGPing-Zhi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期331-334,共4页
Magnetic excitations for Ba isotopes are discussed within the nucleon-pair shell model truncated in the SD subspace. With the SD pair determined by a surface- interaction, M1 transitions for are well fitted. The M1 a... Magnetic excitations for Ba isotopes are discussed within the nucleon-pair shell model truncated in the SD subspace. With the SD pair determined by a surface- interaction, M1 transitions for are well fitted. The M1 and M3 transitions for and are also predicted. It is shown that the statement, the collective magnetic properties are due to the orbital motion of nucleons, is approximately valid. 展开更多
关键词 the nucleon-pair shell model magnetic excitation Ba isotopes
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Attractive fixed-point solution study of shell model for homogeneous isotropic turbulence
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作者 郭昊 李超 +1 位作者 屈秋林 刘沛清 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第3期259-268,共10页
The attractive fixed-point solution of a nonlinear cascade model is stud- ied for the homogeneous isotropic turbulence containing a parameter C, introduced by Desnyansky and Novikov. With a traditional constant positi... The attractive fixed-point solution of a nonlinear cascade model is stud- ied for the homogeneous isotropic turbulence containing a parameter C, introduced by Desnyansky and Novikov. With a traditional constant positive external force added on the first shell equation, it can be found that the attractive fixed-point solution of the model depends on both the parameter C and the external force. Thus, an explicit force is introduced to remove the effects of the external force on the attractive fixed-point solu- tion. F^arthermore, two groups of attractive fixed-point solutions are derived theoretically and studied numerically. One of the groups has the same scaling behavior of the velocity in the whole inertial range and agrees well with those observed by Bell and Nelkin for the nonnegative parameters. The other is found to have different scaling behaviors of the velocity at the odd and even number shells for the negative parameters. This special characteristic may be used to study the anomalous scaling behavior of the turbulence. 展开更多
关键词 TURBULENCE shell model attractive fixed-point SCALING
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Shell Model for Elastic and Thermodynamic Properties of Gallium Nitride with Hexagonal Wurtzite Structure
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作者 CHENG Yan TU Ya-Jing +1 位作者 ZENG Zhao-Yi GOU Qing-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1443-1448,共6页
Shell model molecular dynamic simulation with interatomic pair potential is utilized to investigate the elastic and thermodynamic properties of gallium nitride with hexagonal wurtzite structure (w-GaN) at high press... Shell model molecular dynamic simulation with interatomic pair potential is utilized to investigate the elastic and thermodynamic properties of gallium nitride with hexagonal wurtzite structure (w-GaN) at high pressure. The calculated elastic constants Cij at zero pressure and 300 K agree well with the experimental data and other calculated values. Meanwhile, the dependences of the relative volume V/Vo, elastic constants Cij, entropy S, enthalpy H, and heat capacities Cv and Up on pressure are successfully obtained. From the elastic constants obtained, we also calculate the shear modulus G, bulk modulus B, Young's modulus E, Poisson's ratio v, Debye temperature ΘD, and shear anisotropic factor Ashear on pressures. 展开更多
关键词 shell model molecular dynamics elastic properties thermodynamic properties GaN
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Phonon Dispersion and Thermodynamics Properties of CaF_2 via Shell Model Molecular Dynamics Simulations
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作者 CHENG Yan HU Cui-E +2 位作者 ZENG Zhao-Yi GONG Min GOU Qing-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期904-908,共5页
The phonon and thermodynamics properties of face-centered cubic CaF2 at high pressure and high temperature are investigated by using the shell model interatomic pair potential within General Utility Lattice Program (... The phonon and thermodynamics properties of face-centered cubic CaF2 at high pressure and high temperature are investigated by using the shell model interatomic pair potential within General Utility Lattice Program (GULP). The phonon dispersion curves and the corresponding density of state (PDOS) in this work are consistent with the experimental data and other theoretical results. The transverse optical (TO) and longitudinal optical (LO) mode splitting as well as heat capacity at constant volume Cv and entropy S versus pressure and temperature are also obtained. 展开更多
关键词 shell model molecular dynamics phonon dispersion thermodynamic property CAF2
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Probability Distribution Function of Passive Scalars in Shell Models
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作者 ZHANG Xiao-Qiang WANG Guang-Rui CHEN Shi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期1033-1038,共6页
A shell-model version of passive scalar problem is introduced, which is inspired by the model of K. Ohkitani and M. Yakhot [K. Ohkitani and M. Yakhot, Phys. Rev. Lett. 60 (1988) 983; K. Ohkitani and M. Yakhot, Prog.... A shell-model version of passive scalar problem is introduced, which is inspired by the model of K. Ohkitani and M. Yakhot [K. Ohkitani and M. Yakhot, Phys. Rev. Lett. 60 (1988) 983; K. Ohkitani and M. Yakhot, Prog. Theor. Phys. 81 (1988) 329]. As in the original problem, the prescribed random velocity field is Gaussian and 5 correlated in time. Deterministic differential equations are regarded as nonlinear Langevin equation. Then, the Fokker-Planck equations of PDF for passive scalars are obtained and solved numerically. In energy input range (n 〈 5, n is the shell number.), the probability distribution function (PDF) of passive scalars is near the Gaussian distribution. In inertial range (5≤ n ≤ 16) and dissipation range (n ≥ 17), the probability distribution function (PDF) of passive scalars has obvious intermittence. And the scaling power of passive scalar is anomalous. The results of numerical simulations are compared with experimental measurements. 展开更多
关键词 shell model passive scalar distribution function
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Influence of Velocity Shell Correlations on Anomalous Scaling Exponents of Passive Scalars in Shell Models
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作者 ZHANG Xiao-Qiang WANG Guang-Rui CHEN Shi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期211-214,共4页
We propose a new approach to the old-standing problem of the anomaly of the scaling exponents of passive scalars of turbulence. Different to the original problem, the distribution function of the prescribed random vel... We propose a new approach to the old-standing problem of the anomaly of the scaling exponents of passive scalars of turbulence. Different to the original problem, the distribution function of the prescribed random velocity field is multi-dimensional normal and delta-correlated in time. Here, our random velocity field is spatially correlative. For comparison, we also give the result obtained by the Gaussian random velocity field without spatial correlation. The anomalous scaling exponents H(p) of passive scalar advected by two kinds of random velocity above are determined for structure function up to p= 15 by numerical simulations of the random shell model with Runge-Kutta methods to solve the stochastic differential equations. We observed that the H(p) 's obtained by the multi-dimeasional normal distribution random velocity are more anomalous than those obtained by the independent Gaussian random velocity. 展开更多
关键词 shell models passive scalar distribution function
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Shell Model Description of Neutron-Deficient Sn Isotopes
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作者 Erdal Dikmen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期899-903,共5页
The shell model calculations in the sdgh major shell for the neutron-deficient ^106,107,108,109Sn isotopes have been carried out by using CD-Bonn and Nijmegenl two-body effective nucleon-nucleon interactions. The sing... The shell model calculations in the sdgh major shell for the neutron-deficient ^106,107,108,109Sn isotopes have been carried out by using CD-Bonn and Nijmegenl two-body effective nucleon-nucleon interactions. The singleshell states and the corresponding matrix elements needed for describing Sn isotopes are reconstructed to calculate the coefficient of fractional parantage by reducing the calculation requirements. This reconstruction allows us to do the shell model calculations of the neutron deficient Sn isotopes in very reasonable time. The results are compared to the recent high-resolution experimental data and found to be in good agreement with experiments. 展开更多
关键词 shell model low-lying states effective interactions
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A Shell Model Mass Formula for Exotic Light Nuclei
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作者 Mariano Bauer Hugo Garcfa Tecocoatzi Cristian Mojica 《Journal of Physical Science and Application》 2012年第8期306-314,共9页
An analytic phenomenological shell model mass formula for light nuclei is constructed. The formula takes into account the non locality of the self consistent single particle potential and the special features of light... An analytic phenomenological shell model mass formula for light nuclei is constructed. The formula takes into account the non locality of the self consistent single particle potential and the special features of light nuclei, namely: (a) charge and mass distributions are closer to a Gaussian shape than to the shape characteristic in medium and heavy nuclei; (b) the central charge and mass densities are larger than, and decrease towards, the "asymptotic" values that are the reference parameters for nuclear matter; and (c) after a shell closure, the next level has a larger orbital angular momentum and a noticeably larger mean square radius. Only then a good numerical fit is obtained with parameters consistent with optical model analysis and empirical spin-orbit couplings. A correlation between the "skin effect" and the symmetry dependence of the optical potential is established. Towards the neutron drip line the potential well depth, the spin-orbit splitting of the single particle levels and the gap between major shells decrease, as has been observed. The ensuing shift and contraction of the single particle level scheme may lead to: (a) to strong configuration mixing and new magic numbers, and (b) the onset of the halo effect, to avoid the expulsion of single particle levels to the continuum. 展开更多
关键词 Light nuclei features shell model mass formula skin effect halo effect.
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Prediction of Radioactive Half-Lives and Atomic Nucleus Dimensions in a Concentric Shell Model or Flocon Model
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作者 Marc Mignonat 《Journal of Modern Physics》 CAS 2022年第8期1216-1251,共36页
Considering only the wave aspect, we determine the energy of a bond between 2 nucleons;this quantified energy is associated with a standing wave. Then, starting from the mass loss corresponding to this energy, we dete... Considering only the wave aspect, we determine the energy of a bond between 2 nucleons;this quantified energy is associated with a standing wave. Then, starting from the mass loss corresponding to this energy, we determine the number of bonds in this nucleus. The mass defect value for a link is used to determine a specific length at that link. Fixing a precise distance between nucleons makes it possible to determine a geometry of the nucleus and its dimensions. It makes it possible to understand when this bond is stronger than the electrostatic force and allows deducing a shell model built in a precise order. The calculation on the mass defect will also make it possible to determine that one or more nucleons concerned by the radioactivity will be bound by a single bond to the rest of the nucleus or, on the contrary, bound by several bonds which induce short 1/2 lives or, on the contrary, very long. The analysis of the bonds on H, He and C make it possible to write formulae which are then applied to the nuclei to find the radioactive 1/2 lives. To find by equations the radioactive 1/2 lives does not call into question the standard model since it concerns only the defect of mass of the nuclei with energies that are not used to find the main particles of the standard model. This model, which favours a geometric approach to the detriment of a mathematical approach based on differential equations, can lead to theoretical questions about the possibility of interpreting the structure of the nucleus in a more undulatory way. It is possible to explain radioactivity in a more deterministic way. 展开更多
关键词 ½ Radioactive Lives Atomic Nucleus Dimensions shell model
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Astrophysics: Macroobject Shell Model 被引量:3
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期776-790,共15页
The model proposes that Nuclei of all macroobjects (Galaxy clusters, Galaxies, Star clusters, Extrasolar systems) are made up of Dark Matter Particles (DMP). These Nuclei are surrounded by Shells composed of both Dark... The model proposes that Nuclei of all macroobjects (Galaxy clusters, Galaxies, Star clusters, Extrasolar systems) are made up of Dark Matter Particles (DMP). These Nuclei are surrounded by Shells composed of both Dark and Baryonic matter. This model is used to explain various astrophysical phenomena: Multi-wavelength Pulsars;Binary Millisecond Pulsars;Gamma-Ray Bursts;Fast Radio Bursts;Young Stellar Object Dippers;Starburst Galaxies;Gravitational Waves. New types of Fermi Compact Stars made of DMP are introduced: Neutralino star, WIMP star, and DIRAC star. Gamma-Ray Pulsars are rotating Neutralino and WIMP stars. Merger of binary DIRAC stars can be a source of Gravitational waves. 展开更多
关键词 HYPERSPHERE World-Universe model Medium of the World Macroobject shell model Dark Matter Particles Gamma-Ray BURSTS Fast Radio BURSTS Multiwavelength PULSARS Binary MILLISECOND PULSARS Young Stellar Object Dippers STARBURST Galaxies Gravitational Waves
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Study of rotational bands of ^(129)La using the projectedshell model
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作者 WANG Zixing SHEN Shuifa +3 位作者 SHI Shuanghui GU Jiahui LIU Jingyi ZHU Zhiyuan (Shanghai Institute of Nuclear Research, the Chinese Academy of Sciences, Shanghai 201800) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1999年第3期149-154,共6页
The projected shell model is applied to the nucleus 129La. The present results of theoretical calculations about the one-quasiproton bands are compared with experimental data. The agreement with both the yrast πh11/2... The projected shell model is applied to the nucleus 129La. The present results of theoretical calculations about the one-quasiproton bands are compared with experimental data. The agreement with both the yrast πh11/2 band πg7/2 band is satisfactory. We also assign the πg7/2 [νh11/2]2 configuration with an oblate shape for one of bands in 129La. 展开更多
关键词 奇数质子核 129La 高层模型 旋转能带
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Shell Model Investigation of High Spin States for Ce Isotopes
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作者 Sang, Jianping Liu, Yong 《Chinese journal of nuclear physics》 EI 1994年第2期146-152,共7页
-A truncated shell model approach is presented for studying the properties oflow-lying states as well as the high-spin states in even-even nuclei with the help of thegeneralized boson-fermion expansion technique.The p... -A truncated shell model approach is presented for studying the properties oflow-lying states as well as the high-spin states in even-even nuclei with the help of thegeneralized boson-fermion expansion technique.The primary fermion state space isspanned by the interacting valence protons and neutrons with effective nucleon-nucleonforce.The truncated model space is considered as a direct sum of two subspaces corre-sponding to the configurations of(sd)<sup>N</sup> and(sd)<sup>N-1</sup>,respectively,plus a broken fermionpair.Numerical calculations are carried out for <sup>130~134</sup>Ce isotopes.The calculated spec-trum reproduces the experimental data quite well,especially the backbending appearingin these nuclei.The results suggest that the approach is able to describe the spectroscopyof states with angular momenta up to J≈20. 展开更多
关键词 Truncated shell model BOSON-FERMION expansion 130~134Ce ISOTOPES HIGH-SPIN states
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Shell stand:Stable thin shell models for 3D fabrication
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作者 Yu Xing Xiaoxuan Wang +3 位作者 Lin Lu Andrei Sharf Daniel Cohen-Or Changhe Tu 《Computational Visual Media》 SCIE EI CSCD 2024年第4期643-657,共15页
A thin shell model refers to a surface or structure,where the object’s thickness is considered negligible.In the context of 3D printing,thin shell models are characterized by having lightweight,hollow structures,and ... A thin shell model refers to a surface or structure,where the object’s thickness is considered negligible.In the context of 3D printing,thin shell models are characterized by having lightweight,hollow structures,and reduced material usage.Their versatility and visual appeal make them popular in various fields,such as cloth simulation,character skinning,and for thin-walled structures like leaves,paper,or metal sheets.Nevertheless,optimization of thin shell models without external support remains a challenge due to their minimal interior operational space.For the same reasons,hollowing methods are also unsuitable for this task.In fact,thin shell modulation methods are required to preserve the visual appearance of a two-sided surface which further constrain the problem space.In this paper,we introduce a new visual disparity metric tailored for shell models,integrating local details and global shape attributes in terms of visual perception.Our method modulates thin shell models using global deformations and local thickening while accounting for visual saliency,stability,and structural integrity.Thereby,thin shell models such as bas-reliefs,hollow shapes,and cloth can be stabilized to stand in arbitrary orientations,making them ideal for 3D printing. 展开更多
关键词 surface models thin shell models optimization BALANCE stability 3D fabrication
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基于SHELL模型的航空货物运输安全问题研究
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作者 钟波兰 龙海燕 《长沙航空职业技术学院学报》 2024年第3期82-87,共6页
文章阐述了SHELL 模型的基本理论,分析了航空货物运输的基本流程及常见安全问题,应用SHELL模型重点探究航空货物运输中人与硬件(L-H)、人与软件(L-S)、人与环境(L-E)及人与人(L-L)的要素特征与关系界面,梳理引发安全问题导致不安全事件... 文章阐述了SHELL 模型的基本理论,分析了航空货物运输的基本流程及常见安全问题,应用SHELL模型重点探究航空货物运输中人与硬件(L-H)、人与软件(L-S)、人与环境(L-E)及人与人(L-L)的要素特征与关系界面,梳理引发安全问题导致不安全事件的原因,提出缩小关系界面空隙、提高关系匹配度的措施,保障航空货物运输安全,促进航空货运持续稳定发展。 展开更多
关键词 shell模型 航空货物运输 安全
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基于邻域K-shell分布的关键节点识别方法 被引量:3
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作者 吴亚丽 任远光 +3 位作者 董昂 周傲然 吴学金 郑帅龙 《计算机工程与应用》 CSCD 北大核心 2024年第2期87-95,共9页
复杂网络中关键节点的精准识别对于网络结构稳定和信息传播起着至关重要的作用。传统K-shell方法仅通过节点在网络中所处位置对节点的重要性进行评估,导致区分度不高。基于此,综合考虑了节点的全局信息和局部信息对节点重要性的影响,提... 复杂网络中关键节点的精准识别对于网络结构稳定和信息传播起着至关重要的作用。传统K-shell方法仅通过节点在网络中所处位置对节点的重要性进行评估,导致区分度不高。基于此,综合考虑了节点的全局信息和局部信息对节点重要性的影响,提出一种基于邻域K-shell分布的关键节点识别方法。该方法通过节点邻域Ks值定义节点的熵,从而反映邻居节点的K-shell分布特征。通过11个网络数据集上的仿真实验,验证了所提方法能够更准确地识别并区分复杂网络中的关键节点。 展开更多
关键词 复杂网络 关键节点 K-shell 易感-感染-恢复模型(SIR)
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基于K-shell的加权网络节点影响力研究方法
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作者 吴思源 许爽 《大连民族大学学报》 CAS 2024年第5期444-448,共5页
针对现有关键节点识别方法在准确性和分辨率上的局限性,提出了一种改进的K-shell排序方法,在传统K-shell分解的基础上,结合节点度数、邻居节点影响力和边权重,引入信息熵理论,细化同一K-shell层内节点的相对重要性。实验结果表明:该方... 针对现有关键节点识别方法在准确性和分辨率上的局限性,提出了一种改进的K-shell排序方法,在传统K-shell分解的基础上,结合节点度数、邻居节点影响力和边权重,引入信息熵理论,细化同一K-shell层内节点的相对重要性。实验结果表明:该方法显著提升了排序的准确性和单调性,能够更有效地区分同一K-shell层内的节点重要性,准确识别出对网络结构影响较大的关键节点。该算法从多个维度考虑影响关键节点识别重要性的因素,在准确性和分辨率方面有显著的提升,对网络匿名隐私保护中的关键节点挖掘具有重要意义。 展开更多
关键词 节点重要性 K-shell 加权网络 SIR模型 复杂网络
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC Electron POSITRON COULOMB Force ATTRACTION REPULSION Wave Function Electric Magnetic Radiation Pressure shell THEOREM 3D Computer model Quantum
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