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International Journal of Mining Science and Technology 2019年第2期29卷 263-272页

作者： Xiaofei Guo Zhiqiang Zhao Xu Gao Xiangye Wu Nianjie Ma Faculty of Resource and Safety Engineering China University of Mining and Technology (Beijing) Department of Energy and Mineral Engineering The Pennsylvania State University University Park Institute of Mining Engineering Inner Mongolia University of Science and Technology

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.

关键词： Inhomogeneous stress field Analytical solutions Characteristic radii Morphological identification Disaster area

Nuclear Interaction radii for Light Exotic Nuclei

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Chinese Physics Letters 1993年第7期10卷 401-404页

作者： FENG Jun SHEN Wenqing MA Yugang Institute of Nuclear Research Academia SinicaShanghai 201800

We developed a simple model to calculate the interaction radii for light neutron-rich nuclei based on Coulomb-modified Glauber *** 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.

关键词： interaction separation radii

Theoretical study on characteristic ionic radii

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Chinese Science Bulletin 1998年第17期43卷 1452-1455页

作者： Zhongzhi Yang Guohui Li Dongxia Zhao Hongbin He Renan Sun Liaoning Normal Univ Dept Chem & Phys Dalian 116029 Peoples R China

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.

关键词： univalent cations and anions characteristic radii %ab-initio% method.

Ionic effective radii under high-temperatures state

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Chinese Science Bulletin 1997年第15期42卷 1265-1268页

作者： FU ZhengminInstitute of Physics, Chinese Academy of Sciences, Beijing 100080, China Institute of Physics Chinese Academy of Sciences Beijing 100080 China

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 KIO3-CsIO3

关键词： high temperature ionic effective radii ionic compounds.

Real stability radii and quadratic matrix inequality

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Chinese Science Bulletin 1996年第24期41卷 2043-2046页

作者：胡庭姝黄琳 Department of Automation Shanghai Jiaotong University Shanghai 200030 China Department of Mechanics and Engineering Sciences Peking University Beijing 100871 China

In the sequel,we suppose system （2） to be Cg-stable,i.e.Cg is a given open set in thecomplex plane and all the eigenvalues of A are in Cg.Both B∈Rn×m and C∈Rp×n are giv-en.Δ∈Rm×p is an unknown perturbation *** 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.

关键词： parameter perturbations real stability radii quadratic matrix inequality.

EFFECT OF IONIC radii ON UNIT-CELL VOLUMES OF ISOSTRUCTURAL COMPOUNDS

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Science China Chemistry 1989年第8期32卷 1014-1024页

作者：张金民叶大年 Institute of Geology Academia Sinica Beijing

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.

关键词： isostructural compounds unit-cell volumes ionic radii

A GENERAL EQUATION FOR CALCULATING THE SINGLE BOND radii R(1)OF ACTINIDES

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Chinese Science Bulletin 1991年第22期36卷 1871-1873页

作者：陈秀芳左秀忠余瑞璜钱存富 Department of Physics Northeast University of Technology Shenyang 110006 PRC Department of Physics Jilin University Changchun 130023 PRC

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.,

关键词： single bond radii actinides

A descriptor of “material genes”: Effective atomic size in structural unit of ionic crystals

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Science China(Technological Sciences) 2019年第5期62卷 849-855页

作者： CHEN Dong LI ShunNing JIE JianShu LI SiBai ZHENG ShiSheng WENG MouYi YU ChangCheng LI ShuCheng CHEN DaJun PAN Feng School of Advanced Materials Shenzhen Graduate School Peking University

The atomic size of each element, described by the ionic radius, is one category of "material genes" and can facilitate our understanding of atomic arrangements in compounds. Most of the ionic radii currently used to measure the sizes of cations and anions in ionic crystals are derived from hard-sphere model based on the coordination numbers, or the soft-sphere model incorporating the effect of ionic polarization. Herein we take a first step towards a novel "effective atomic size"(EAS) model,which takes into consideration the impact of the types and number of neighboring atoms on the relationship between ionic radii and interatomic distances. Taking the binary compounds between Group IA/IIA and VIA/VIIA elements gathered from the latest databases as an example, we show that the proposed EAS model can yield excellent agreement between the predicted and the DFT-calculated interatomic distances, with deviation of less than 0.1 ?. A set of EAS radii for ionic crystals has been compiled and the role of coordination numbers, geometric symmetry and distortion of structural units has been examined. Thanks to its superior predictability, the EAS model can serve as a foundation to analyze the structure of newly-discovered compounds and to accelerate materials screening processes in the future works.

关键词： ionic radii interatomic distance effective atomic size coordination environment structural units

Average Property of Isospin Effects Induced by Neutron-Halo Nuclei

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Chinese Physics Letters 2006年第10期23卷 2710-2713页

作者：刘建业肖国青左维李希国 Institute of Modern Physics Chinese Academy of Sciences PO Box 31 Lanzhou 730000 Institute of Basic Physics College of Mathematics-Physics and Information Tianshui Normal University Tianshui 741000 Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000

We study the average property of the isospin effects of reaction mechanism induced by neutron-halo nuclei within the isospin-dependent quantum molecular dynamics model. We find that the extended neutron density distribution for the neutron-halo projectile brings an important isospin effect into the reaction mechanism, which induces the decrease of nuclear stopping R; however, it induces the obvious increases of the neutron-proton ratio of nucleon emissions （n/p）nucl for all of the beam energies in this work, compared to the same mass stable colliding system.

关键词： HEAVY-ION COLLISIONS INTERACTION CROSS-SECTIONS MODEL FRAGMENTATION radii BE-14

Sensitive Probe for Symmetry Potential

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Chinese Physics Letters 2007年第3期24卷 660-663页

作者：刘建业肖国青郭文军任中洲左维李希国 Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 Institute of Modern Physics Chinese Academy of Sciences PO Box 31 Lanzhou 730000 Institute of Basic Physics College of Mathematics-Physics and Information Tianshui Normal University Tianshui 741000 Department of Physics Nanjing University Nanjing 210008 5Science College University of Shanghai for Science and Technology Shanghai 200093 Science College University of Shanghai for Science and Technology Shanghai 200093

Based on both very obvious isospin effect of the neutron-proton number ratio of nucleon emissions （n/p）nud on symmetry potential and （n/p）nucl＇s sensitive dependence on symmetry potential in the nuclear reactions induced by halo-neutron projectiles, compared to the same mass stable projectile, probing symmetry potential is investigated within the isospin-dependent quantum molecular dynamics with isospin and momentum-dependent interactions for different symmetry potentials U;ym and U2^sym. It is found that the neutron-halo projectile induces very obvious increase of （n/p）nucl and strengthens the dependence of （n/p） l on the symmetry potential for all the beam energies and impact parameters, compared to the same mass stable projectile under the same incident channel condition. Therefore （n/p）nucl induced by the neutron-halo projectile is a more favourable probe than the normal neutron-rich and neutron-poor projectiles for extracting the symmetry potential.

关键词： HEAVY-ION COLLISIONS INTERACTION CROSS-SECTIONS FRAGMENTATION ENERGIES NUCLEI radii MODEL