弱相互作用费米气体的热力学性质

根据赝势法导出无外势时弱相互作用费米气体的化学势、内能和定容热容的解析表达式.在此基础上，采用局域密度近似研究谐振势中弱相互作用费米气体的热力学性质，探讨粒子间相互作用对系统性质的影响. 关键词： 费米气体 相互作用 赝势法 局域密度近似 热力学性质     

有限系统中的若干热力学问题

对偏离热力学极限条件的有限系统中的若干基本热力学问题作些探讨.结果表明,尺度效应使系统产生一系列新的物理特性,使得统计物理教科书中诸多人们熟悉的结论对有限系统不再适用.     

理想量子气体的尺度效应

根据欧拉-麦克劳林(Euler-MacLaurin)公式,导出有限理想量子气体的热力学量表达式,揭示系统尺度和边界形状对其性质的影响.结果表明,有限尺度效应导致了一系列与热力学极限条件下不同的性质特征,如系统的非广延性和压强的各向异性等.     

玻色-爱因斯坦凝聚的相变特征

研究玻色-爱因斯坦凝聚的相变特征，证明了粒子间存在弱排斥相互作用的玻色系统的玻色-爱因斯坦凝聚是二级相变。     

对"入射粒子能量为阈能时的核反应是完全非弹性碰撞"的更一般性证明

给出“入射粒子能量为阈能时的核反应是完全非弹性碰撞”这一结论的更一般性证明.     

Oscillating Casimir force between two slabs in a Fermi sea

The Casimir effect for two parallel slabs immersed in an ideal Fermi sea is investigated at both zero and nonzero temperatures. It is found that the Casimir effect in a Fermi gas is distinctly different from that in an electromagnetic field or a massive Bose gas. In contrast to the familiar result that the Casimir force decreases monotonically with the increase of the separation L between two slabs in an electromagnetic field and a massive Bose gas, the Casimir force in a Fermi gas oscillates as a function of L. The Casimir force can be either attractive or repulsive, depending sensitively on the magnitude of L. In addition, it is found that the amplitude of the Casimir force in a Fermi gas decreases with the increase of the temperature, which also is contrary to the case in a Bose gas, since the bosonic Casimir force increases linearly with the increase of the temperature in the region T < T_c, where T_c is the critical temperature of the Bose-Einstein condensation.     

Oscillating Casimir force between two slabs in a Fermi sea

The Casimir effect for two parallel slabs immersed in an ideal Fermi sea is investigated at both zero and nonzero temperatures.It is found that the Casimir effect in a Fermi gas is distinctly different from that in an electromagnetic field or a massive Bose gas.In contrast to the familiar result that the Casimir force decreases monotonically with the increase of the separation L between two slabs in an electromagnetic field and a massive Bose gas,the Casimir force in a Fermi gas oscillates as a function of L.The Casimir force can be either attractive or repulsive,depending sensitively on the magnitude of L.In addition,it is found that the amplitude of the Casimir force in a Fermi gas decreases with the increase of the temperature,which also is contrary to the case in a Bose gas,since the bosonic Casimir force increases linearly with the increase of the temperature in the region T相似文献   

概念测试题对同伴教学法的影响

哈佛大学 Eric M azur 创立的同伴教学法通过概念测试题引导学生进行自主与合作学习,促进了师生和学生间的互动,有效提高了教学效果。本文借助教学互动系统,在本科物理类基础课程中引入同伴教学法,探讨概念测试题对于教学效果的影响。结果表明课程设计中根据授课对象的知识结构等特点设置难易程度适中的概念测试题,可以有效检测学生对于物理概念的掌握程度、激发学生自主与合作学习的积极性、提高课堂效率和教学效果。     

斯特林热机的基本优化关系及功率和效率界限

1前言近年来,有些学者应用有限时间热力学研究斯特林热机的优化性能,获得一些比经典热力学界限更有意义的新性能界限。但至今为数还较少,应继续开展研究。特别是有人提出“21世纪是斯特林热机的世纪’巾一］。本文将进一步研究受热阻、热漏和回热损失三种主要不可逆因素影响的斯特林热机的优化性能,导出热机的基本优化关系及功率和效率界限。结果表明,热漏的存在使斯特林热机的优化性能与无热漏时的有质的差异,而在热阻和回热损失的基础上再考虑热漏的影响,其结果将可反映出实际热机观测性能的主要特征【’,‘］,从而对实际更有指…     

Finite-size effects in a D-dimensional ideal Fermi gas

By using the Euler-MacLaurin formula,this paper studies the thermodynamic properties of an ideal Fermi gas confined in a D-dimensional rectangular container.The general expressions of the thermodynamic quantities with the finite-size corrections are given explicitly and the effects of the size and shape of the container on the properties of the system are discussed.It is shown that the corrections of the thermodynamic quantities due to the finite-size effects are significant to be considered for the case of strong degeneracy but negligible for the case of weak degeneracy or non-degeneracy.It is important to find that some familiar conclusions under the thermodynamic limit are no longer valid for the finite-size systems and there are some novel characteristics resulting from the finite-size effects,such as the nonextensivity of the system,the anisotropy of the pressure,and so on.