浅谈物理实验教学与综合能力培养

物理是一门以观察和实验为基础的学科,在物理教学中每一个概念的建立和规律的发现都是建立在实验的基础上,搞好实验教学是提高物理教学质量的重要环节,是培养学生的综合能力的有效途径,在以往的教学中,往往是以学生的考试成绩来评价学生,而现在提倡的是素质教育,更注重学生的综合能力和创新意识,实验教学也就成了教学中最重要的环节,下面就物理实验教学与学生的综合能力培养谈谈自己的看法。     

基于分数导数研究高强度聚焦超声的非线性声场

在高强度聚焦超声(high intensity focused ultrasound, HIFU) 的研究中, 生物组织的衰减和色散性质会对声能量的空间分布产生影响. 本文提出应用分数导数修正非线性Khokhlov-Zabolotskaya-Kuznetsov (KZK)方程, 研究生物组织中非线性HIFU声场. 对三种生物仿体的衰减和声速色散的理论实验研究表明分数导数应用的可行性, 在此基础上通过数值仿真分析研究了衰减及声速随频率的变化对HIFU焦域分布的影响. 研究结果表明, 在计算强非线性聚焦超声时, 由于高次谐波的强色散作用, 引入分数导数来解决生物组织特殊的衰减以及色散问题可进一步提高HIFU治疗的安全性. 关键词： 分数导数 声衰减 色散 高强度聚焦超声     

UO2 晶体中低密勒指数晶面表面能的分子动力学模拟

采用基于刚性离子势的分子动力学模拟方法初步计算了UO₂晶体中(100), (110)和(111) 3种低密勒指数晶面在300–1500 K范围内的表面能大小. 结果表明, 3种晶面的表面能大小随温度的升高而降低, 与实验结果趋势一致; 原子排列最紧密的(111)晶面具有最低的表面能, 3种晶面的表面能大小从高到低依次为(100), (110)和(111)晶面; 达到平衡状态下的表面层原子相对于体内原子层在表面的法线方向上发生了明显的压缩并且表面层原子的对称性也降低了, 表面原子的弛豫效应一直影响到了第5层. 计算研究结果将有助于深入认识UO₂燃料中裂变气体气泡的聚集长大以及燃料的辐照肿胀开裂行为. 关键词： 分子动力学 2')" href="#">UO₂ 低密勒指数晶面 表面能     

气垫导轨的计算机辅助数据采集系统的设计

研制了基于USB接口的新型光电门,结合虚拟软件Audition 1.5与计算机声卡设计了一套计算机辅助数据采集系统,用于研究气垫导轨上滑块的运动规律.     

数学无穷与中介逻辑(上)——Leibniz的割线与切线问题在中介逻辑中的逻辑数学解释方法(英文)

From the perspective of potential infinity (poi) and actual infinity, Ref [4] has confirmed that poi and aci are in ’unmediated opposition’ (P,﹁P ) whether in ZFC or not; it has further been proved that the manners in which a variable infinitely approaches its limit also satisfy the law of intermediate exclusion. With these results as theoretical bases, this paper attempts to provide an accurate and strict logical-mathematical interpretation of the incompatibility of Leibniz’s secant and tangent lines in the medium logic system from the perspective of logical mathematics.     

A diagrammatic categorification of the fermion algebra

In this paper, we study the diagrammatic categorification of the fermion algebra. We construct a graphical category corresponding to the one-dimensional （1D） fermion algebra, and we investigate the properties of this category. The categorical analogues of the Fock states are some kind of 1-morphisms in our category, and the dimension of the vector space of 2-morphisms is exactly the inner product of the corresponding Fock states. All the results in our categorical framework coincide exnetlv with those in normal quantum mechanics.     

饲用微生物添加剂的研究与应用进展

饲用微生物添加剂的种类繁多,作用机理不尽相同.概述了饲用微生物添加剂的研究与应用进展,对指导畜牧业生产有着非常重要的意义.     

Generation of GHZ States via Deterministic Entanglement Concentration

We present the generation of six-particle Greenberger Horne-Zeilinger （GHZ） states via deterministic entanglement concentration and generalize the scheme to the case of 2N particles. We show that arbitrary 2N-particle GHZ states can be obtained with certain probability via entanglement concentration. This may provide a new perspective for the preparation of multi-particle GHZ states. This study is also an exploration on the theory of deterministic entanglement concentration.     

Symmetric Telecloning and Entanglement Distribution of Spin Quantum States

We propose a physical realization of symmetric telecloning machine for spin quantum states. The concept of area average fidelity is introduced to describe the telecloning quality. It is indicated that for certain input states this quantity may come to an enough high level to satisfy the need of quantum information processing. We also study the properties of entanglement distribution via the spin chain for arbitrary two-qubit entangled pure states as inputs and find that the decay ratio of entanglement for the output states is only determined by the parameters of spin chain and waiting time, independent of the initial input states.     

Self-Injection and Acceleration of Monoenergetic Electron Beams from Laser Wakefield Accelerators in a Highly Relativistic Regime

Self-injection and acceleration of monoenergetic electron beams from laser wakefield accelerators are first investigated in the highly relativistic regime, using 100 TW class, 27 fs laser pulses. Quasi-monoenergetic multi- bunched beams with energies as high as multi-hundredMeV are observed with simultaneous measurements of side-scattering emissions that indicate the formation of self-channelfing and self-injection of electrons into a plasma wake, referred to as a ＇bubble＇. The three-dimensional particle-in-cell simulations confirmed multiple self-injection of electron bunches into the bubble and their beam acceleration with gradient of 1.5 GeV/cm.