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Cabibbo-Suppressed Non-leptonic Decays of ∧c and Final State Interaction

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Communications in Theoretical Physics 2003年第5X期40卷 563-572页

作者： CHENShao-Long GUOXin-Heng liXue-Qian wangguo-li Departmentof.Physics NankaiUniversityTianjin300071China DepartmentofPhysicsandMathematicalPhysics andSpecialResearchCenterfortheSubatomicStructureofMatterAdelaideUniversitySA5005Australia CCAST(WorldLaboratory) P.O.Box8730Beijing100080China InstituteofTheoreticalPhysics AcademiaSinicaBeijing100080China

With the diquark structure of ∧c, we investigate the branching ratio of ∧c→nπ^+ and pπ^0. The results show that without considering the finM state interaction (FSI), the branching ratio of ∧c→pπ^0 is only of order 10^-6 whereas this ratio could reach 10^-4 and is at the same order as ∧c→nπ^+ if taking into account the FSI effects. Concrete values depend on phenomenologicM parameters adopted in the calculations. These branching ratios can be measured in the experiments to come.

关键词：重夸克作用理论定夸克结构分歧率轻子延迟高能物理学

Instantaneous Bethe-Salpeter Equation and Its Exact Solution

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Communications in Theoretical Physics 2005年第1期43卷 113-118页

作者： CHANGChao-Hsi CHENJiao-Kai liXue-Qia wangguo-li CCAST（WorldLaboratory） P.O.Box8730Beijing100080China／／InstituteofTheoreticalPhysicstheChineseAcademyofSciencesP.O.Box2735Beijing100080China InstituteofTheoreticalPhysics theChineseAcademyofSciencesP.O.Box2735Beijing100080China／／GraduateSchooloftheChineseAcademyofSciencesBeijing100039China CCAST（WorldLaboratory） P.O.Box8730Beijing100080China／／DepartmentofPhysicsNankaiUniversityTianjin300071China DepartmentofPhysics NankaiUniversityTianjin300071China／／DepartmentofPhysicsFujianNormalUniversityFuzhou350007China

We present an approach to solve Bethe-Salpeter (BS) equations exactly withoutany approximation if the kernel of the BS equations exactly is instantaneous, and take positroniumas an example to illustrate the general features of the exact solutions. The key step for theapproach is from the BS equations to derive a set of coupled and well-determined integrationequations in linear eigenvalue for the components of the BS wave functions equivalently, which maybe solvable numerically under a controlled accuracy, even though there is no analytic solution. Forpositronium, the exact solutions precisely present corrections to those of the correspondingSchrodinger equation in order υ~1 (υ is the relative velocity) for eigenfunctions, in order υ~2for eigenvalues, and the mixing between S and D components in J~(PC) = 1~(--) states etc.,quantitatively. Moreover, we also point out that there is a questionable step in some existentderivations for the instantaneous BS equations if one is pursuing the exact solutions. Finally, weemphasize that one should take the O(υ) corrections emerging in the exact solutions into accountaccordingly if one is interested in the relativistic corrections for relevant problems to the boundstates.

关键词： instantaneous BS equation exact solutions positronium relativisticcorrections

Non-spectator Contributions to lifetime of ∧b

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Communications in Theoretical Physics 2004年第5X期42卷 723-734页

作者： CHANGChao-Hsi GUOPeng liXue-Qian wangguo-li InstituteofTheoreticalPhysics AcademiaSinicaP.O.Box2735Beijing100080China DepartmentofPhysics NankaiUniversityTianjin300071China

In this work, we study the contributions of non-spectator effects to the lifetimes of Λb and B-mesons comparatively. Based on the well-established theoretical framework about the effective weak Lagrangian, we derive the formulation of the non-spectator effects at the quark level. Especially, for Λb we have considered two pictures: the three-valence-quark picture and the quark-diquark picture. In the two pictures, the interference contributions to the total width are different, in this work, we investigate the interference effects in detail. As a preliminary estimate on the lifetimes, we evaluate the hadronic matrix elements appearing in the final formulas of the lifetimes by means of a simple phenomenological model for both pictures. Our results show that the contributions of the non-spectator effects can reduce the ratio of lifetime of Λb to that of B-mesons by 5 ～ 7%. It is noted that in the quark-diquark picture the ratio can be further reduced if excited states of the diquark system are taken into account. We conclude that the measured ratio τ(Λb)/τ(B0)(≈)0.79 [The Data Group, Phys. Rev. D66 (2002) 010001] can be partly understood by the non-spectator effects, although the problem on the discrepancy between theoretical prediction and experimental measurement is not fully solved.

关键词：寿命粒子物理学重夸克效应衰退轨道

资本的逐利性与教育的公益性——民办高校的“非营利性”探讨

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中国高教研究 2010年第10期 46-46,47,48页

作者：李望国白云学院教务长副教授广东广州510450

民办高等教育组织是典型的市场化的产物,其提供的教育产品的社会性要求民办高校具有公益性,"非营利性"是我国教育类法规的统一要求。而民办高校的资本来源的非政府性,甚至产业性,决定了民办高校资本天生而潜在的逐利性。民办高校存在着... 详细信息

民办高等教育组织是典型的市场化的产物,其提供的教育产品的社会性要求民办高校具有公益性,"非营利性"是我国教育类法规的统一要求。而民办高校的资本来源的非政府性,甚至产业性,决定了民办高校资本天生而潜在的逐利性。民办高校存在着资本逐利性与教育公益性的矛盾。政府应对"投资办学"与"捐资办学"、"营利性"与"非营利性"民办教育加以区分并给予法律认定,这是一种切合我国实际的做法,将更有利于我国民办教育的发展。

关键词：民办高校非营利组织公益性

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政府职能与民办高校发展研究

高教探索 2011年第1期 112-116页

作者：李望国刘曼琴广东白云学院广东培正学院经济系

以独立设置民办高校为研究对象,结合我国民办教育发展实践,分析我国民办高等教育发展的特殊性,剖析独立建制民办高校面临的制度缺陷、经费不足、竞争不公等发展障碍,分析民办高校发展中政府职能存在的问题,提出对策与建议。

关键词：政府职能民办高等教育独立设置民办高校发展战略

闪烧合成高熵氧化物陶瓷(MgCoNiCuZn)O的性能

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无机材料学报 2022年第12期37卷 1289-1294页

作者：李汪国刘佃光王珂玮马百胜刘金铃西南交通大学材料科学与工程学院成都610031 东莞理工学院机械工程学院东莞523808 西南交通大学力学与航空航天学院成都610031

闪烧技术是一种温度场与电场耦合的烧结技术,具有低温快速传质的特性,在高熵陶瓷的合成上具有显著的优势。本研究通过闪烧法合成了相对致密的高熵氧化物陶瓷(MgCoNiCuZn)O,并与传统烧结试样的性能进行了对比。在室温,电场强度为50 V/cm... 详细信息

闪烧技术是一种温度场与电场耦合的烧结技术,具有低温快速传质的特性,在高熵陶瓷的合成上具有显著的优势。本研究通过闪烧法合成了相对致密的高熵氧化物陶瓷(MgCoNiCuZn)O,并与传统烧结试样的性能进行了对比。在室温,电场强度为50 V/cm,电流密度为300 mA/mm^(2)条件下闪烧,物相转变的时间仅为10 s。闪烧试样最高相对密度为94%,比传统烧结试样最高密度提高了22.8%。闪烧试样的最高硬度5.05GPa,比传统烧结试样高3.95 GPa。当频率<2Hz时,闪烧试样的介电常数比传统烧结试样高一个数量级。闪烧试样性能的提高,一方面与临界电场加速传质,提高材料致密度有关;另一方面与临界电场引入额外的缺陷有关。

关键词：高熵氧化物闪烧相变介电常数