惯性系和非惯性系教学设计--实验创新,探究引路,突破教学难点

教学设计是体现课标理念，深化课堂教学改革的一项重要教学研究．本刊第1期征文肩事关于“研究性教学案例”专题，已引起各方重视，现发表一篇颇具创新的教学设计案例，供参考，欢迎大家踊跃参加探讨．[编者按]     

Electronic Properties of Red P-Type Tl2S5 Single Crystals

Single crystals of red Tl2S5 were prepared by a special modified vertical Bridgman and Stockbarger technique.This growth was performed in our laboratory. The influences of temperature on the electrical conductivity, Hall mobility, carrier concentration, and thermoelectric power (TEP) were carried out in the temperature range 277-413K. Throughout these measurements, various physical parameters such as effective mass of charge carriers,carrier mobility, diffusion coefficient, and the relaxation time for both majority and minority carriers were found.     

超声波作用下的制冷剂水合物结晶过程研究

首先分析了超声波对制冷剂水合物成核生长的影响机理,然后进行了实验研究。结果表明,超声波对水合物的结晶生长有明显的影响,阶梯形的超声探头作用下的成核引导时间比指数形锥体引导时间长,促进水合物生长的超声波功率P范闱是58W相似文献   

物理课导语设计的讨论

导语是授课前的启发、诱导．目的是将学生的思维从课间引导到课堂上；启发思维、指导学习,激发学生强烈的求知欲望和浓郁的学习兴趣,为学生学习新知识搭桥铺路,使其思有方向,求有目标,获有所新,用有所创．教学实践告诉我们：优良的教学环境,有利于启迪学生的智慧,陶冶学生的情操,而富有魅力的导语,是创建良好课堂环境,使教师、学生均进入最佳角色的前奏,是教师在备课当中精心设计,艺术构思的结晶,也是教师     

溶胶—凝胶法制备SiO2基片Er^3＋：Al2O3光学薄膜

用溶胶—凝胶法在SiO2基片上提拉制备了掺Er^3 ：Al2O3光学薄膜。采用扫描电子显微镜、原子力显微镜、差热—热重分析仪、X射线衍射仪研究了掺Er^3 ：Al2O3光学薄膜的肜貌和结构特性。在900℃烧结后，SiO2基片上提拉15次形成厚度8μm掺摩尔比0．01Er^3 的面心立方结构γ-Al2O3薄膜具有明显(110)择优取向，掺摩尔比0．01Er^3 对γ—Al2O3的品体结构和结晶生长过程木产生显著影响。薄膜具有均匀多孔结构，平均粒径为30～100nm，平均孔径为50～100nm，表面起伏度为10～20nm。掺摩尔比0．01Er^3 ：rAl2O3薄膜，获得了中心波长为1．534μm(半峰全宽为36nm)的光敛发光谱。     

Low-Temperature Growth of Polycrystalline silicon Films by SiCl4／H2 rf Plasma Enhanced Chemical Vapour Deposition

Polycrystalline silicon film was directly fabricated at 200℃ by the conventional plasma enhanced chemical vapour deposition method from SiCl4 with H2 dilution. The crystallization depends strongly on the deposition power.The maximum crystMlinity and the crystalline grain size are over 80% and 200—50Onm, respectively. The results of energy dispersive spectroscopy and infrared spectroscopy measurements demonstrate that the film is mostly composed of silicon, without impurities such as Cl, N, C and bonded H. It is suggested that the crystallization at such a low temperature originates from the effects of chlorine, i.e., in-situ chemical, etching, in-situ chemical cleaning, and the detachment of bonded H.     

一种求解混合多目标规划问题的功效函数法

逻辑生长函数相对于龚珀兹生长函数具有拐点高和对称性的特点,采用逻辑生长函数形式的功效函数法求解混合多目标规划问题具有形式简单、计算量小、符合实际的优点。证明了用这种方法求出的最优解是有效解。讨论了满意值对有效解的影响。逻辑生长函数还可以应用于多维变量评价的功效系数法中。     

高中数学课堂中合作学习实施的设计策略研究

教育部2003年4月颁布实施的普通高中《数学课程标准(实验)》[1]中强调指出:丰富学生的学习方式,改进学生的学习方法,是高中数学课程追求的基本理念.倡导学生积极主动、勇于探索的学习方式,明确指出学生学习数学不是接受、记忆、模仿和练习,而应是自主探索、合作交流、动手操作、阅读自学、充满了创新思考的过程.合作学习是新课程所大力倡导的三种主要学习方式之一,如何设计合理、有效的合作学习实施方案,需要有具体的合作学习实施策略为指导.所谓“设计策略”,就是教师为实现教学目标或教学意图而采取的一系列具体的问题解决行为方式.高中数…     

Effect of Incident Intensity on Films Growth in Pulsed Laser Deposition

Incident intensity, defined by the amount of particles deposited per pulse, is an important parameter in the film growth process of pulsed laser deposition （PLD）. Different from previous models, we investigate the irreversible and reversible growth processes by using a kinetic Monte Carlo method and find that island density and film morphology strongly depend on pulse intensity. At higher pulse intensities, lots of adatoms instantaneously diffuse on the substrate surface, and then nucleation easily occurs between the moving adatoms resulting in more smaller-size islands. In contrast, at the lower pulse intensities, nucleation event occurs preferentially between the single adatom and existing islands rather than forming new islands, and therefore the average island size becomes larger in this case. Additionally, our results show that substrate temperature plays an important role in film growth. In particular, it can determine the films shape and weaken the effect of pulse intensity on film growth at the lower temperatures by controlling the mobility rate of atoms. Our results can match the related theoretical and experimental results.