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Constraining nuclear symmetry energy with the charge radii of mirror-pair nuclei 被引量:6
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作者 Rong An Shuai Sun +1 位作者 Li-Gang Cao Feng-Shou Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第8期154-163,共10页
The nuclear charge radius plays a vital role in determining the equation of state of isospin asymmetric nuclear matter.Based on the correlation between the differences in charge radii of mirror-partner nuclei and the ... The nuclear charge radius plays a vital role in determining the equation of state of isospin asymmetric nuclear matter.Based on the correlation between the differences in charge radii of mirror-partner nuclei and the slope parameter(L)of symmetry energy at the nuclear saturation density,an analysis of the calibrated slope parameter L was performed in finite nuclei.In this study,relativistic and nonrelativistic energy density functionals were employed to constrain the nuclear symmetry energy through the available databases of the mirror-pair nuclei^(36)Ca–^(36)S,^(38)Ca–^(38)Ar,and ^(54)Ni–^(54)Fe.The deduced nuclear symmetry energy was located in the range 29.89–31.85 MeV,and L of the symmetry energy essentially covered the range 22.50–51.55 MeV at the saturation density.Moreover,the extracted L_(s) at the sensitivity density p_(s)=0.10 fm^(-3) was located in the interval range 30.52–39.76 MeV. 展开更多
关键词 Symmetry energy Charge radii Mirror nuclei
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Predictions of nuclear charge radii based on the convolutional neural network 被引量:1
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作者 Ying-Yu Cao Jian-You Guo Bo Zhou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第10期83-90,共8页
In this study, we developed a neural network that incorporates a fully connected layer with a convolutional layer to predict the nuclear charge radii based on the relationships between four local nuclear charge radii.... In this study, we developed a neural network that incorporates a fully connected layer with a convolutional layer to predict the nuclear charge radii based on the relationships between four local nuclear charge radii. The convolutional neural network(CNN) combines the isospin and pairing effects to describe the charge radii of nuclei with A ≥ 39 and Z ≥ 20. The developed neural network achieved a root mean square(RMS) deviation of 0.0195 fm for a dataset with 928 nuclei. Specifically, the CNN reproduced the trend of the inverted parabolic behavior and odd–even staggering observed in the calcium isotopic chain, demonstrating reliable predictive capability. 展开更多
关键词 Nuclear charge radii Machine learning Neural network
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Analytical solutions for characteristic radii of circular roadway surrounding rock plastic zone and their application 被引量:16
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作者 Xiaofei Guo Zhiqiang Zhao +2 位作者 Xu Gao Xiangye Wu Nianjie Ma 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第2期263-272,共10页
In the non-uniform stress field, the surrounding rock plastic zone of the circular roadway shows different shapes under the different confining pressure conditions. Based on the boundary shape characteristics of the p... In the non-uniform stress field, the surrounding rock plastic zone of the circular roadway shows different shapes under the different confining pressure conditions. Based on the boundary shape characteristics of the plastic zone, the characteristic radii of the plastic zone were proposed, namely the horizontal,longitudinal and medial axis radii, which could reflect the plastic zone shapes characteristics and classify the sizes of the key parts. On the theoretical basis of elastic-plastic mechanics, analytical solutions for the characteristic radii were obtained by theoretical deduction, and the relationships between the characteristic radii and key influencing factors were analyzed. Finally, the evaluation criterion of the circular roadway surrounding rock plastic zone shapes, evaluation criterion of the location of potential hazards caused by the roadway surrounding rock and evaluation critical points of roadway dynamic disasters based on characteristic radii were proposed. This work could provide a theoretical basis for stability analysis of the surrounding rock, support design, and guide the prevention and control of dynamic roadway disasters. 展开更多
关键词 INHOMOGENEOUS stress field Analytical solutions CHARACTERISTIC radii Morphological identification Disaster area
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Crystal Radii and Their Application on the Study of Electronic Structures of LaX(X=N,P,As,Sb)
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作者 孟庆波 武志坚 张思远 《分子科学学报》 CAS CSCD 1998年第1期3-8,共6页
以Philips-VanVechten理论和晶体光学性质为基础,计算了LaX(X=N,P,As,Sb)晶体的离子半径(单位:nm):(La:N)为(0.1414,0.1236),(La:P)为(0.1518,0.14... 以Philips-VanVechten理论和晶体光学性质为基础,计算了LaX(X=N,P,As,Sb)晶体的离子半径(单位:nm):(La:N)为(0.1414,0.1236),(La:P)为(0.1518,0.1489),(La:As)为(0.1536,0.1526),(La:Sb)为(0.1586,0.1651).用LMTO-ASA方法对LaX系列晶体的能带结构进行了计算.所得到的能隙是:LaN为2.30eV,LaP为2.05eV,LaAs为1.66eV,LaSb为1.34eV.与实验结果相符.这也证明了作者得到的半径的合理性. 展开更多
关键词 LaX(X=N`P`As`Sb) 晶体半径 LMTO-ASA 能隙
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Polymer Radii and Moments in the Polycondensation Reaction of A_a Type
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作者 Li Zesheng, Sun Jiazhong, Ba Xinwu and Tang Aoqing (Institute of Theoretical Chemistry, Jilin University, Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第4期370-372,共3页
For the polycondensation reaction of A. type, the kth radius for k>2 can be expressed in terms of polymer moments.
关键词 Polymer radii Polymer moment POLYCONDENSATION
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Representations of Real and Complex Stability Radii of 2-Dimensional LinearSystems
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作者 Lequan Min1.2 Ning Song1(l Applied Science School, University of Science and Technology’ Beijing, Beijing 100083, China2 China Center of Advanced Science and Technology, Beijing 100080, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第4期299-301,共3页
Rigorous proofs are given for the representations of real and complex stability' radii of 2-dimensional linear systems. This representations can be used to analyze the robustness of a nominal 2-dimensional linear ... Rigorous proofs are given for the representations of real and complex stability' radii of 2-dimensional linear systems. This representations can be used to analyze the robustness of a nominal 2-dimensional linear system under pelturbation of the system parameters, in particular testing the effect of numerical algorithms which are used to calculate the real stability radii of higher dimensional piecewise-linear systems. 展开更多
关键词 linear systems ROBUSTNESS stability radii
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Nuclear Interaction Radii for Light Exotic Nuclei
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作者 FENG Jun SHEN Wenqing MA Yugang 《Chinese Physics Letters》 SCIE CAS CSCD 1993年第7期401-404,共4页
We developed a simple model to calculate the interaction radii for light neutron-rich nuclei based on Coulomb-modified Glauber model.Considering a relation of surface diffuseness of neutron distribution with the neutr... We developed a simple model to calculate the interaction radii for light neutron-rich nuclei based on Coulomb-modified Glauber model.Considering a relation of surface diffuseness of neutron distribution with the neutron separation energy of nucleus,the large increasing of nuclear interaction radii for exotic nuclei(such as ^(6)He,^(8)He,^(11)Li,^(11)Be)on ^(12)C target can be reasonably explained. 展开更多
关键词 INTERACTION SEPARATION radii
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Magnetic Moments and Electromagnetic Radii of Nucleon and △(1232) in an Extended Goldstone-Boson-Exchange Model
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作者 HEJun Yu-Bing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期139-146,共8页
We derive the exchange currents of pseudoscalar, vector, and scalar mesons from Feynman diagrams, and use them to calculate the magnetic form factors of nucleon and △(1232). The magnetic moments and electromagnetic r... We derive the exchange currents of pseudoscalar, vector, and scalar mesons from Feynman diagrams, and use them to calculate the magnetic form factors of nucleon and △(1232). The magnetic moments and electromagnetic radii are obtained by using those form factors and the parameters determined from the masses of nucleon and △(1232).We find the magnetic moments and electromagnetic radii of nucleon and △(1232) can be produced very well in the extended Goldstone-Boson-exchange model in which all of pseudoscalar, vector, and scalar meson nonet are included.The magnetic moments of △(1232) are closer to experiment values and results from lattice calculation than the results obtained by the model without other mesons except for pion and sigma. 展开更多
关键词 magnetic moments electromagnetic radii nucleon and Δ(1232) extendedgoldstone-boson-exchange model
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Semi-Empirical Formulas for Nuclear Charge Radii
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作者 Wang, Jiansong Shen, Wenqing +1 位作者 Feng, Jun Ye, Wei 《Chinese journal of nuclear physics》 EI 1997年第1期23-30,共8页
Considering the relationship between the nuclear radius and the average bindingenergy of nucleons,a simple semi-empirical formula for the nuclear rms charge radii is suggest-ed together with the formula for light neut... Considering the relationship between the nuclear radius and the average bindingenergy of nucleons,a simple semi-empirical formula for the nuclear rms charge radii is suggest-ed together with the formula for light neutron-rich nuclear rms neutron radii.These formulascan well fit the new experimental values. 展开更多
关键词 Root-mean-square(rms)radii BINDING ENERGY Separation ENERGY Relativemean-field(RMF)
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Predictions of nuclear charge radii
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作者 李光胜 橙许 鲍曼 《Chinese Physics C》 SCIE CAS CSCD 2023年第8期75-80,共6页
In this study,we improve the relations of the charge-radius difference of two isotopes by considering a term that relates to the proton number and the parity of the neutron number.The correction reduces the root-mean-... In this study,we improve the relations of the charge-radius difference of two isotopes by considering a term that relates to the proton number and the parity of the neutron number.The correction reduces the root-mean-squared deviation to 0.0041 fm for 651 nuclei with a neutron number larger than 20,in comparison with experiment-al data compiled in the CR2013 database.The improved relations are combined with local relations consisting of the charge radii of four neighboring nuclei.These combinations also prove to be efficient in describing and predicting nuclear charge radii and can reflect the structure evolutions of nuclei.Our predictions of 2467 unknown nuclear charge radii at competitive accuracy,which are calculated using these two types of relations,are tabulated in the Supplemental Material. 展开更多
关键词 nuclear charge radii ISOTOPES root-mean-squared deviation
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STARLIKENESS ASSOCIATED WITH THE SINE HYPERBOLIC FUNCTION
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作者 Mohsan RAZA Hadiqa ZAHID Jinlin LIU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1244-1270,共27页
Let q_(λ)(z)=1+λsinh(ζ),0<λ<1/sinh(1)be a non-vanishing analytic function in the open unit disk.We introduce a subclass S^(*)(q_(λ))of starlike functions which contains the functions f such that zf'/f i... Let q_(λ)(z)=1+λsinh(ζ),0<λ<1/sinh(1)be a non-vanishing analytic function in the open unit disk.We introduce a subclass S^(*)(q_(λ))of starlike functions which contains the functions f such that zf'/f is subordinated by q_(λ).We establish inclusion and radii results for the class S^(*)(q_(λ))for several known classes of starlike functions.Furthermore,we obtain sharp coefficient bounds and sharp Hankel determinants of order two for the class S^(*)(q_(λ)).We also find a sharp bound for the third Hankel determinant for the caseλ=1/2. 展开更多
关键词 starlike functions sine hyperbolic functions radii problems coefficient bounds Hankel determinants
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Solution of the Nucleon Structure Problem from a Field Theory of Fermions and Bosons and the Origin of the Proton Stability
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作者 Hans-Peter Morsch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1655-1669,共15页
A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor r... A bound state formalism derived from a fermion-boson symmetric Lagrangian has been used to calculate the nucleon masses, the charge neutrality of the neutron, the magnetic moments and the electromagnetic form factor ratios μpGEp/GMpand μnGEn/GMn. A quantitative description is obtained, assuming a mixing of a scalar bound state of 3(f f¯)fstructure with its corresponding vector (f f¯)fstate (f indicating massless elementary fermions). Only a few parameters are needed, mainly fixed by energy and momentum conservation. The nucleon stability is explained by an extra binding in the confinement potential, negative for electric and positive for magnetic binding of the proton, and opposite for the neutron. The stronger electric extra binding of the proton allows a decay of the neutron to proton and electron. 展开更多
关键词 Proton and Neutron Properties Described in a New Bound State Formalism by a Mixing of Two Related Bound States Quantitative Agreement with Their Masses radii Magnetic Moments and Electromagnetic Form Factor Ratios High Stability Due to Extra Binding in the Confinement Potential
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Evolution of nuclear charge radii in copper and indium isotopes 被引量:1
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作者 Rong An Xiang Jiang +1 位作者 Li-Gang Cao Feng-Shou Zhang 《Chinese Physics C》 SCIE CAS CSCD 2022年第6期138-146,共9页
Systematic trends in nuclear charge radii are of great interest due to universal shell effects and odd-even staggering(OES).The modified root mean square(rms)charge radius formula,which phenomenologically accounts for... Systematic trends in nuclear charge radii are of great interest due to universal shell effects and odd-even staggering(OES).The modified root mean square(rms)charge radius formula,which phenomenologically accounts for the formation of neutron-proton(np)correlations,is here applied for the first time to the study of odd-Z copper and indium isotopes.Theoretical results obtained by the relativistic mean field(RMF)model with NL3,PK1 and NL3^(*)parameter sets are compared with experimental data.Our results show that both OES and the abrupt changes across N=50 and 82 shell closures are clearly reproduced in nuclear charge radii.The inverted parabolic-like behaviors of rms charge radii can also be described remarkably well between two neutron magic numbers,namely N=28 to 50 for copper isotopes and N=50 to 82 for indium isotopes.This implies that the np-correlations play an indispensable role in quantitatively determining the fine structures of nuclear charge radii along odd-Z isotopic chains.Also,our conclusions have almost no dependence on the effective forces. 展开更多
关键词 nuclear charge radii neutron-proton correlations relativistic mean field theory odd-even staggering shell closure
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Real stability radii and quadratic matrix inequality
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作者 胡庭姝 黄琳 《Chinese Science Bulletin》 SCIE EI CAS 1996年第24期2043-2046,共4页
In the sequel,we suppose system (2) to be C<sub>g</sub>-stable,i.e.C<sub>g</sub> is a given open set in thecomplex plane and all the eigenvalues of A are in C<sub>g</sub>.Both B∈... In the sequel,we suppose system (2) to be C<sub>g</sub>-stable,i.e.C<sub>g</sub> is a given open set in thecomplex plane and all the eigenvalues of A are in C<sub>g</sub>.Both B∈R<sup>n×m</sup> and C∈R<sup>p×n</sup> are giv-en.Δ∈R<sup>m×p</sup> is an unknown perturbation matrix.In the following,σ(·)is used to de-scribe the maximum singular value of the matrix;R(·) and N(·) are the column spaceand null space of matrix respectively. 展开更多
关键词 parameter PERTURBATIONS REAL STABILITY radii QUADRATIC matrix inequality.
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Ionic effective radii under high-temperatures state
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作者 FU ZhengminInstitute of Physics, Chinese Academy of Sciences, Beijing 100080, China 《Chinese Science Bulletin》 SCIE EI CAS 1997年第15期1265-1268,共4页
REFERENCES [1, 2] prove that ionic radii will increase or decrease with temperature rising orlowering. If the ionic radii at room temperature are known, many phenomena of the ioniccompounds occurring at room temperatu... REFERENCES [1, 2] prove that ionic radii will increase or decrease with temperature rising orlowering. If the ionic radii at room temperature are known, many phenomena of the ioniccompounds occurring at room temperature can be explained. Also if the ionic radii at high tem-perature are known, many phenomena of the ionic compounds occurring at high temperaturecan also be explained. Therefore, to calculate the effective radii of ions at high temperature isconsidered of great significance. For example, the 'investigation of KIO<sub>3</sub>-CsIO<sub>3</sub> 展开更多
关键词 high temperature IONIC EFFECTIVE radii IONIC compounds.
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A GENERAL EQUATION FOR CALCULATING THE SINGLE BOND RADII R(1)OF ACTINIDES
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作者 陈秀芳 左秀忠 +1 位作者 余瑞璜 钱存富 《Chinese Science Bulletin》 SCIE EI CAS 1991年第22期1871-1873,共3页
Ⅰ. INTRODUCTION The valence state changes of actinides are complicated by their electron structures, because the valence electron structures of an element are different in different compounds. For this reason, study ... Ⅰ. INTRODUCTION The valence state changes of actinides are complicated by their electron structures, because the valence electron structures of an element are different in different compounds. For this reason, study on the electron structures of metals and compounds of actinides is of important theoretical significance. The equation for calculating the single bond radii R(1) and the hybrid levels of valence 3 actinides have been established by Chen et al., 展开更多
关键词 single BOND radii ACTINIDES
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EFFECT OF IONIC RADII ON UNIT-CELL VOLUMES OF ISOSTRUCTURAL COMPOUNDS
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作者 张金民 叶大年 《Science China Chemistry》 SCIE EI CAS 1989年第8期1014-1024,共11页
The relation between cell-edges or unit-cell volumes of isostructural compounds and theionic radii has wide applications in crystal chemistry. The authors have proved: (1) For a series of multiple isostructural compou... The relation between cell-edges or unit-cell volumes of isostructural compounds and theionic radii has wide applications in crystal chemistry. The authors have proved: (1) For a series of multiple isostructural compounds such as A_mB_n…X_p, when the anionand other cations are fixed, there exists the following relation between the unit-cell volume Vand the radius r_A of a certain cation such as A: V = (a + br_A)(r_X + r_A)~3 (a and b are constants). (2) For binary isostructural compounds A_mX_p, the above relation is reduced to V = k(r_X + r_A)~3 (k is a constant). (3) For binary isostructural compounds the relation between V and r_A^3 is approximatelylinear, and for multiple compounds, it is often curvilinear but still approximately linear whenthe variation of r_A is slight. As another approximation, a linear relation also exists betweenV and r_A for isostructural compounds. (4) The relation of ce1l-edge a vs. r_A is linear for binary isostructural compounds. Butno such a good linear relation exists for multiple isostructural compounds. 展开更多
关键词 ISOSTRUCTURAL COMPOUNDS UNIT-CELL VOLUMES IONIC radii
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Theoretical study on characteristic ionic radii 被引量:4
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作者 Zhongzhi Yang Guohui Li +2 位作者 Dongxia Zhao Hongbin He Renan Sun 《Chinese Science Bulletin》 SCIE EI CAS 1998年第17期1452-1455,共4页
The characteristic radii for univalent cations and anions were defined by the classical turning point of the electron movement in an ion. The numerical results of the elements from first- to third-rows in the periodic... The characteristic radii for univalent cations and anions were defined by the classical turning point of the electron movement in an ion. The numerical results of the elements from first- to third-rows in the periodic table were obtained using %ab initio% method. The results correlate quite well with Pauling ionic radii and Shannon and Prewitt ionic radii. 展开更多
关键词 UNIVALENT CATIONS and ANIONS CHARACTERISTIC radii %ab-initio% method.
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变基圆涡旋式压缩机多刚柔耦合动力学特性分析
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作者 柴红阳 胡欣 +1 位作者 何泽银 孙权 《制冷与空调》 2024年第1期87-94,共8页
为阐明汽车空调涡旋压缩机转子系统摩擦副非稳态动态激励机理,建立变基圆涡旋式压缩机多刚柔耦合动力学模型,以变基圆涡旋压缩机气体力为边界条件,研究轴系摩擦副动态接触激励;而后,基于变基圆涡旋式压缩机多刚柔耦合动力学模型,对动态... 为阐明汽车空调涡旋压缩机转子系统摩擦副非稳态动态激励机理,建立变基圆涡旋式压缩机多刚柔耦合动力学模型,以变基圆涡旋压缩机气体力为边界条件,研究轴系摩擦副动态接触激励;而后,基于变基圆涡旋式压缩机多刚柔耦合动力学模型,对动态接触激励进行影响因素分析。结果表明,动态接触激励力的频率响应峰值主要出现在100Hz、200Hz、700Hz与2300Hz及其边频处,为转频的整数倍次与动涡盘的1/2倍频处;为降低变基圆涡旋式压缩机轴系摩擦损耗,应合理设置防自转机构间隙及个数。 展开更多
关键词 变基圆 涡旋压缩机 转子系统 刚柔耦合 汽车空调
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两异径湿球颗粒间静态液桥力的近似解析公式及数值评测
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作者 李艳洁 邱洋平 +1 位作者 徐泳 黄文彬 《计算力学学报》 CAS CSCD 北大核心 2023年第1期86-92,共7页
针对异径球形湿颗粒间液桥力,以Young-Laplace公式为基础,结合环形近似法并引入等效半径,在宽松设定的条件下推导出了简化的近似解析公式。此公式形式简洁,且当两球半径相等时,可回归到Pitois等提出的径球液桥力公式。本文对此近似解析... 针对异径球形湿颗粒间液桥力,以Young-Laplace公式为基础,结合环形近似法并引入等效半径,在宽松设定的条件下推导出了简化的近似解析公式。此公式形式简洁,且当两球半径相等时,可回归到Pitois等提出的径球液桥力公式。本文对此近似解析公式进行参数敏感度分析,发现随着颗粒间距的增大,液桥力对颗粒半径的敏感度降低。此外,本文近似解析公式与其他实验和理论结果进行对比发现,该近似解析公式与上述实验和数值结果相当吻合,表明该近似解析公式可以较准确地计算接触角较小时的异径球颗粒间的液桥力,因而适于湿颗粒系统的数值模拟。 展开更多
关键词 液桥 毛细力 异径球颗粒 接触角
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