《霍尔效应原理及其应用》的误差消除

首先引导学生自己发现这一实验事实,然后要求学生注意这个问题,并要求学生对其产生的原因进行大胆的猜想,充分发挥学生的主体作用,这样既培养了学生的探究能力,又培养了学生交流、表达能力,使学生的动手能力、思维能力,得到协调发展．     

建立以学生为主体的物理教学

现代教育观念强调以学生本,以学生的进步发展为目标,突出学生在教育活动中的主体地位．所谓主体是指从事活动的人,学生的主体性是指学生作为学习活动的主体在学习过程中表现出的能动性、创造性和自主性．而主体教育就是培养学生的主人公责任感,使学生树立起自信、自立、自尊、自强的精神．如何建立以学生为主体的教学?我想更新教育观念,     

浅谈物理备课中的备学生

教师在备课时,要备教材、备教法、备学生等。对于备学生,很多老师当成了套话、空话,在实际备课中忽视了备学生这个环节。下面笔者根据自己的教学经验,浅谈一下物理教学中为什么要备学生,怎样备学生,以及备学生存在的一些误区。一、为什么要备学生1.确定教学内容的需要在教学中,有两类问题不适合讲。一类是,不用讲学生已经会了的内容,另一类是,讲了学生也不会的内容。到底哪些内容属于上述两种情况,需要教师根据学生的实际情况来确定,而不是通过教师的揣度来确定。     

改革命题思路和考试办法 提高薄弱学校教学水平

考试在整个教学过程中占有重要的地位,因为考试可以评估、鉴定学生的知识与技能是否达到规定的水平和标准;可以检测学生知识、技能的掌握程度,给学生提供改进学习的信息,给教师提供调整和改进教学的信息;可以提高学生的素质、能力和预测学生的潜能及未来发展趋势;可以提高和强化学生     

新教材(人教版)必修模块实验的设计特色和教学价值分析

分析了人教版新教材必修模块中实验的设计特色及所表现出的教学价值.从新技术手段在实验中的应用、各栏目的实验统一规划、引领学生进行深度学习、促进学生的物理学科核心素养的达成、实验装置图等5个方面分析了教材实验的设计特色,从独立小节学生实验对于学生探究能力全面提升的价值、学生的动手实验和做一做体验活动在帮助学生构建知识和能力...     

物理实验考核模式改革与体会

普通物理实验是对高等院校学生进行科学实验基本训练的一门必修基础课,是培养学生实践能力与创新能力必需的教学内容．物理实验要解决学生的观察能力、实验操作能力、设想推理能力、收集实验观察资料的能力以及处理实验数据和综合表达能力等等．同时培养学生实事求是的科学态度．传统的考试方法难以激励学生的主动性、积极性、     

在初中物理教学中引入物理学史的调查与尝试

物理学史的学习是学生认识物理现象、掌握物理规律、解决物理问题、探究物理世界的最好导师,也是培养学生刻苦毅力的宝贵财富.初中阶段,由于教学大纲的限制,学生通过课本获取的知识,已经很难满足学生强烈的好奇心与求知欲,作为物理教师,适当地普及物理学史,有助于拓宽学生视野,培养学生勤奋刻苦的学习品质.     

理论力学课堂教学效果的思考与探讨

针对理论力学课程的特点与学生的学习现状,从课堂内容、教学方式等方面进行了研究分析,探讨在新的教学理念下,如何激发学生的学习兴趣、开阔学生的视野、发挥学生的潜力以及培养学生的创新意识,从而为教学效果的提高和教育目标的实现提供了新的思路。     

营造合作学习氛围 转变学生学习方式

长期以来，许多物理教师不适应当今高节奏、大容量、自主开放的教学思路，仍采用“教师为主、学生为辅”的教师讲、学生听教学模式，学生处于消极的、被动的局面，学生的主动性、创造性因此受到抑制．     

新课标下中学物理实验教学方法的探讨

简要分析了中学物理实验教学的现状,根据新课改对物理实验教学的改革和发展提出的要求,分别从演示实验、分组实验、课外实验探讨了中学实验教学方法. 在实验教学过程中突出学生主体,促进学生自主学习,让学生积极参与,乐于探究,勇于实验,勤于思考. 通过实验教学激发学生学习兴趣,提高学生动手能力、观察能力和思维能力,培养学生探索创新能力.     

Time domain finite volume method for the transient response and natural characteristics of structural-acoustic coupling in an enclosed cavity

A time domain finite volume method（TDFVM）based on wave theory is developed to analyze the transient response and natural characteristics of structural-acoustic coupling problems in an enclosed cavity.In the present method,the elastic dynamic equations and acoustic equation in heterogeneous medium are solved in solid domains and fluid domains respectively.The structural-acoustic coupling is implemented according to the continuity condition of the particle velocity along the normal direction and the normal traction equilibrium condition on the interface.Several numerical examples are presented to validate the effectiveness and accuracy of the present TDFVM.Then the effects of water depth on the acoustic and vibration characteristics and the natural characteristics of a structural-acoustic coupling system are analyzed.The numerical results show that the increase of water depth leads to a stronger coupling between the water and structure and the decrease of natural frequencies of coupling system,The computational cost and memory of this method are small and it can be applicable to structural-acoustic coupling problems in the heterogeneous fluid.     

Music,empathy and cultural understanding

In the age of the Internet and with the dramatic proliferation of mobile listening technologies, music has unprecedented global distribution and embeddedness in people's lives. It is a source of intense experiences of both the most intimate and solitary, and public and collective, kinds – from an individual with their smartphone and headphones, to large-scale live events and global simulcasts; and it increasingly brings together a huge range of cultures and histories, through developments in world music, sampling, the re-issue of historical recordings, and the explosion of informal and home music-making that circulates via YouTube. For many people, involvement with music can be among the most powerful and potentially transforming experiences in their lives. At the same time, there has been increasing interest in music's communicative and affective capacities, and its potential to act as an agent of social bonding and affiliation. This review critically discusses a considerable body of research and scholarship, across disciplines ranging from the neuroscience and psychology of music to cultural musicology and the sociology and anthropology of music, that provides evidence for music's capacity to promote empathy and social/cultural understanding through powerful affective, cognitive and social factors; and explores ways in which to connect and make sense of this disparate evidence (and counter-evidence). It reports the outcome of an empirical study that tests one aspect of those claims, demonstrating that ‘passive’ listening to the music of an unfamiliar culture can significantly change the cultural attitudes of listeners with high dispositional empathy; presents a model that brings together the primary components of the music and empathy research into a single framework; and considers both some of the applications, and some of the shortcomings and problems, of understanding music from the perspective of empathy.     

2D-Mueller-matrix tomography of optically anisotropic polycrystalline networks of biological tissues histological sections

A new technique of Mueller-matrix mapping of the birefringent structure of biological preparations of human organs tissues is suggested. The algorithms of reconstruction of average values and magnitude of fluctuations of the phase (birefringence) and amplitude (dichroism) of optically anisotropic structure of myocardium and connective tissue component of the vaginal wall histological section are proposed. The magnitudes and ranges of changes in the statistical moments of the 1st-4th order that characterize the distribution of average values and magnitude of fluctuations of birefringence and dichroism of the myocardium and connective tissue of the vaginal tissues histological sections were determined. Joint studies of distributions of the characteristics of phase and amplitude of the anisotropy of myocardium and connective tissue component of the vaginal wall tissues of different states were performed. The cases of various necrotic changes in the myocardium and pathological conditions of the vagina wall (prolapse of the genitals) are examined. Balanced accuracy of the method of Mueller-matrix polarization-phase and diffuse tomography of optically anisotropic polycrystalline networks in the differentiation of necrotic and pathological changes in human organs is determined.     

Design and simulation of the wire scanner for the injector linac of BEPC Ⅱ

BEPC Ⅱ,the upgrade project of Beijing Electron Positron Collider (BEPC),is an accelerator with large beam current and high luminosity,so an efficient and stable injector is required.Several beam diagnostic and monitoring instruments are used.A new diagnostic instrument--wire scanner,has been designed and will be used to nleasure the profile of the linac beam of BEPC Ⅱ.This paper describes the prototype of this system and the cause of heat generating of the wire.Some simulation results of the heat and force by using finite element method software-ANSYS(R),2) are presented and discussed.     

Temperature Sensitivity Control and Mechanical Stress Effect of Boron-Doped Long-Period Fiber Gratings

We will present in this work the quantitative analysis of the relationship between the doping concentrations of GeO 2 and B 2 O 3 in the core and cladding regions and the temperature sensitivity of the resonance wavelength shift in long-period fiber gratings (LPFGs). Based on this analysis, the temperature sensitivity was suppressed and enhanced to 0.002 nm/°C and 0.28 nm/°C, respectively. We will also discuss the effect of the residual mechanical stress on the optical and mechanical properties of LPFGs. In particular, we will present the measurement results of the dependence of the refractive index change and mechanical strength on the residual mechanical stress in the boron-doped fibers with depressed clad and matched clad.     

Modeling Gain Dynamics in EDFAs: Space-Resolved Versus Lumped Models

We present a detailed comparison of dynamic space- and frequency-resolved and lumped erbium-doped fiber amplifier (EDFA) models. The space- and frequency-resolved models are based on an iterative solution of propagation equations for pump, multiple signals, and spectral components of forward and backward propagating amplified spontaneous powers and rate equations for pump, metastable, and ground energy level population densities of erbium ion. In contrast to space-resolved models, the lumped model solves a single ordinary differential equation for time evolution of the length-averaged metastable level population and is therefore substantially less computer time consuming. Both the space, and frequency-resolved and the lumped models give almost identical results when used for an analysis of surviving channel power excursions in concatenated EDFAs fed by multiwavelength signal and add/drop scenarios. For a statistical analysis of output power and signal-tonoise ratio fluctuations in EDFA cascades fed by burst-mode packet traffic, only lumped models can be used.     

Spectroscopic and nano-molecular modeling investigation on the binary and ternary bindings of colchicine and lomefloxacin to Human serum albumin with the viewpoint of multi-drug therapy

Combination of several drugs is often necessary especially during long-term therapy. The competitive binding drugs can cause a decrease in the amount of drug bound to protein and increase the biological active fraction of the drug. The aim of this study is to analyze the interactions of Lomefloxacin (LMF) and Colchicine (COL) with human serum albumin (HSA) and to evaluate the mechanism of simultaneous binding of LMF and COL to protein. Fluorescence analysis was used to estimate the effect of drugs on the protein fluorescence and to define the binding and quenching properties of drugs-HSA complexes. The binding sites for LMF and COL were identified in tertiary structure of HSA with the use of spectrofluorescence analysis. The analysis of fluorescence quenching of HSA in the binary and ternary systems show that LMF does not affect the complex formed between COL and HSA. On the contrary, COL decreases the interaction between LMF and HSA. The results of synchronous fluorescence, resonance light scattering and circular dichroism spectra of binary and ternary systems show that binding of LMF and COL to HSA can induce micro-environmental and conformational changes in HSA. The simultaneous presence of LMF and COL in binding to HSA should be taken into account in the multi-drug therapy, and necessity of using a monitoring therapy owning to the possible increase of the uncontrolled toxic effects. Molecular modeling of the possible binding sites of LMF and COL in binary and ternary systems to HSA confirms the spectroscopic results.     

Astrophysical combustion

There are three main astrophysical combustion systems: the evolution of stars, formation of interstellar dust and particulates, and the transition to hadrons in the early universe. These are described in terms of general combustion concepts, such as ignition, laminar and turbulent flames, detonations, multiphase flows, and particle and soot formation. Viewed in this way, the universe and many of its most important astronomical components are combustion systems, and we should use these as naturally occurring laboratories for exploring new and familiar combustion regimes. A more detailed discussion focuses on one type of combustion system, the ignition and development of turbulent flames in Type Ia supernovae, and the importance of the transition to a detonation.     

陕北侏罗纪富镜煤和富惰煤分子结构的FTIR，XPS和13C NMR表征

侏罗纪优质煤炭资源为煤制油、制气等清洁高效利用提供了丰富的物质基础,其显微组分以富集惰质组为特征,而镜质组与惰质组大分子结构在很大程度上决定了煤的物理化学性质和工艺性能,进而决定了煤炭资源的综合利用效率及附加值。采集并制备了陕北侏罗纪煤田小保当煤矿和柠条塔煤矿的原煤(XR)、富镜质组煤(XV、NV)和富惰质组煤(XI、NI)样品,利用傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)、固体13C核磁共振谱(13C NMR)等手段,结合煤质分析结果,定量表征了不同显微组分富集物分子结构的差异。研究结果表明：XI和NI煤中芳烃结构芳环取代程度低,主要以3个相邻、4~5个相邻的氢原子形式存在,苯环上氢原子较少被其他官能团取代,同时其结构中芳烃C═C骨架振动明显,脂肪结构中亚甲基伸缩振动强度较低,并且甲基含量略高于富镜煤,C═O基团相对含量略高,表明富惰煤有较多含氧桥键相连的芳香结构,其结构中脂族链、脂环基团脱落、断裂以及芳烃富集,支链相对较少且长度较短,芳碳率、芳香度、芳环缩合程度及成熟度较高。XV和NV煤中表面结构中碳的赋存形态“C—C,C—H”,“C—O”的相对含量高于富惰煤,反映其结构中应含较多的芳环取代的脂肪族侧链,XI和NI煤表面结构中氧的赋存形态以“C—O”为主,“C═O”和“COO—”明显高于富镜煤。XV和XI煤的芳碳率分别为57.91%和66.02%,脂甲基碳分别为10.02%和7.84%,质子化芳碳为非质子化芳碳的两倍,XV煤的羰基和羧基碳相对含量较高,两者桥碳和周碳之比分别为0.25和0.40,芳香核结构平均缩合环数分别为2.68和3.03,平均尺寸分别为0.448和0.676 nm,XI煤结构中芳香核以萘和蒽为主,支链化度L_γ分别为0.22和0.19,表明XV比XI存在较多脂肪侧链、饱和环结构,生烃(油)潜力大。     

景德镇仿龙泉青瓷与龙泉青瓷组成特征研究

龙泉青瓷不仅受到了国内外陶瓷爱好者的热捧,还被不同地区广大窑工争相效仿,其中以景德镇明清时期仿制最具代表性。利用能量色散X荧光光谱分析仪对38 件宋、元、明时期的龙泉青瓷以及明代景德镇仿龙泉青瓷进行了测试,并结合烧成温度分析结果,从时空角度对比分析了两地青瓷胎釉组成特征、演变规律和形成原因,有助于了解我国南方青釉瓷的演变发展、相互交流和影响,为不同产地青瓷的断源断代提供了一定的科学依据。