从演示教学经验谈新时代学生之生活科学素养

旨在探讨物理演示应用于教学之效益,及作者推广演示教学活动之经验分享,同时设计问卷调查现代学生之基本生活科学素养,并藉由问卷结果分析物理与非物理专业学生对现代生活科学认知异同之因素.文中另介绍作者为推广物理演示教学所开设之相关课程.     

振动的分解之教学演示实验

频谱分析作为振动的分解之基本内容，在教学中是一个难点．在这篇文章中，使用labview软件制作声音的频谱分析系统，并介绍课上使用的经验．     

物理之美与美的物理教学

 众所周知,物理教学从来不是单一的抽象思维活动,在教学中师生的交流不应仅仅是作为知识概念的交流,还应该是心灵和感情的交流,即“真善美”的绕一,因此,物理教学必须站在更广阔的知识背景上,挖掘教材中的美的因素,运用美学知识,激发学生的求知欲,增强学生的想象力和洞察力。所以物理教学中讲究美是为学生创造接受知识的条件,是提高学习效率的重要手段。物理之美和美的物理教学,可以培养学生的美学素养,使学生在更高的审美情趣中认识美的世界,创造美的未来。 一、科学家对现代物理学之美的追求 物理学史告诉我们,近代物理学是随着文艺复兴运动的兴起而兴起的。文艺复兴运动也使得希腊的科学美学思想在欧洲复活,唤醒了一大批自然科学家。     

缘起不灭——两岸大学物理基础课程教学之成长与交流（2008年海峡两岸物理基础课程教学研讨会暨参访活动之见闻）

2008年5月在上海成功召开了“第十一届华东地区物理基础课程教学研讨会暨2008年海峡两岸物理基础课程教学研讨会”,有14位台湾物理教授、专家组团莅临会议．本刊已于2008年第5、第6期刊登了几位台湾老师在会上的报告文章．会后,由与会的两位台湾老师,邱韵如教授（长庚大学）和戴明凤教授（新竹清华大学）,撰写了长达20多页的总结报告,题为《缘起不灭——两岸大学物理基础课程教学之成长与交流》（2008年海峡两岸物理基础课程教学研讨会暨参访活动之见闻）,该文刊登在台湾物理学会的杂志《物理》2008年第10期上．经有关方面同意,本刊特摘登该文的第六部分,以向读者报告台湾老师参加此次会议的心得、收获与建议．     

教学过程设计——物理教学设计系列讲座之四

教学过程是为实现教学任务和达成教学目标，通过对话、沟通和合作，以动态生成的方式推进教学活动的进程；其基本环节和内在逻辑结构都是动态的．教学过程设计形成的是一个“弹性化”方案，但一般应对教学顺序、教学组织形式、学习方式、教学模式、教学方法、学习环境及课堂管理等方面进行分析和设计．     

教学用光谱仪之改良

介绍一改良的教学用光谱仪（直视分光镜），利用发光二极体在完全黑暗的背景中标示谱线，并读出该位置谱线之刻度，进而求出其波长；克服了同类型教学用光谱仪之缺点（谱线位置之刻度难以精密测量、较暗谱线不易观察等）。     

治学之道在用心

 治学之道无他,用心而已矣:从事教学与科研工作,必须要“推陈出新”.所谓“推陈”,决不是把旧有的经验一概否定;所谓“出新”,也决不是胡思乱想.     

变质量问题的教学之浅见

本文阐明了变质量物体的运动这一内容在理论力学课的教学中的重要地位，提出了学生难以理解和容易混淆的几个问题，介绍了作者在教学实践中的几点做法。     

关于推导麦克斯韦速度分布律教学线索的分析研究

依据当代教学理论提出麦克斯韦速度分布律这一教学课题的教学目标的分析提出进行这一课题教育设计之教学线索。     

缘起不灭——两岸大学物理基础课程教学之成长与交流

2008年5月在上海成功召开了"第十一届华东地区物理基础课程教学研讨会暨2008年海峡两岸物理基础课程教学研讨会",有14位台湾物理教授、专家组团莅临会议.本刊已于2008年第5、第6期刊登了几位台湾老师在会上的报告文章.会后,由与会的两位台湾老师,邱韵如教授(长庚大学)和戴明凤教授(新竹清华大学),撰写了长达20多页的总结报告,题为《缘起不灭——两岸大学物理基础课程教学之成长与交流》(2008年海峡两岸物理基础课程教学研讨会暨参访活动之见闻),该文刊登在台湾物理学会的杂志《物理》2008年第10期上.经有关方面同意,本刊特摘登该文的第六部分,以向读者报告台湾老师参加此次会议的心得、收获与建议.     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Hybrid Wavelength and Code Division Multiple Access in Optical Networks

A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.