小筷子 大道理

 筷子应用之力学篇 筷子应用之光学篇 筷子应用之热学篇     

CVD金刚石膜研究近期进展与应用

简要地总结了ＣＶＤ金刚石膜技术近期研究与开发情况，讨论了金刚石膜工具的热学应用、光学应用及电子学的现状，芨发展趋势，金刚石膜工具的应用是近期具有最大市场的应用。但随首在沉积技术和异质外延技术的进一步突破，金刚石膜光学和电子学应用将比工具应用具有更加光明的市场前景。     

红外光谱法在纸张分析中的应用

红外光谱法作为一种应用广泛的光谱分析手段,在纸张分析中有重要的应用,其应用范围不断得到拓展,本文综述了红外光谱法在纸张分析中的应用。     

面向虚拟试验的可视化应用生成工具研究与实现

虚拟试验能够很好的辅助实物试验,缩短型号研制周期,降低研制费用。虚拟试验应用工程是开展虚拟试验的基础,本文基于GEF图形编辑器,研究并实现了一种面向虚拟试验可视化应用生成工具,具有可视化应用工程编辑、应用工程框架代码生成等功能。支持在可视化界面中定义VOM图元和APP图元之间的发布、订阅关系,最终生成应用工程框架,并通过应用实例验证了该可视化应用生成工具的实用性,较好的提高了虚拟试验应用工程的开发效率。     

基于聚焦透镜的微扫描应用

微扫描有多种应用方法,若应用方法选择不当会增加控制难度或引入新的成像问题。介绍了一种基于聚焦透镜的微扫描应用,包括应用原理及组成、应用实例及其装调、应用效果。实践表明,这种微扫描方式不仅提高了焦平面阵列的成像质量,而且没有引入新的成像问题,可以满足红外焦平面阵列成像的需求。     

浅谈几何学在物理中的几种应用

1三角形在矢量计算中的应用在矢量的合成和分解中,我们应用平行四边形定则进行运算,其实在运算过程中,主要是运用三角形性质解决问题.那么,三角形在矢量运算中,有哪些应用?1.1相似三角形的应用     

机器视觉及其应用(系列讲座)第五讲机器视觉的典型应用

主要介绍机器视觉的典型应用，简要分析机器视觉的特点、优越性和应用分类，详细介绍了机器视觉技术在印刷行业、农业、工业、医学中的应用，并且分别举例说明。机器视觉的诞生和应用在理论和实际中均具有重要意义。     

高等学校应用物理学本科指导性专业规范

随着我国高等教育规模的不断扩大和人才需求结构的变化,近年来我国多所高校增设了一批专业方向各异的应用物理学本科专业。为了进一步加强全国高等学校应用物理学本科专业建设,规范应用物理学本科专业教学,教育部高等学校物理学与天文学教学指导委员会物理学类专业教学指导分委员会根据教育部高等教育司的要求,重新制定应用物理学本科指导性专业规范,以适应我国高校应用物理学本科专业人才培养的需要。     

应用超导研究中心

应用超导研究中心，致力于高温超导强电和弱电基础和应用研究。2001年4月中心研制的Bi系高温超导导线，被评为2001年中国十大科技新闻.2002年研制成功我国第一台移动通信用的高温超导滤波器系统。2004年高温超导滤波器系统在中国联通基站应用成功，实现了我国高温超导研究18年后的首次实际应用，也使我国成为继美国之后将高温超导应用于移动通信的第二个国家。2005年在北京建成了我国第一个高温超导移动通信应用示范基地。2005年Bi系导线的制备和大规模应用获得北京市科技进步一等奖。应用超导研究中心     

霍尔传感器及其在物理实验中的应用

介绍了霍尔传感器的原理以及工程应用中的霍尔传感器种类 ,举例说明了开关型霍尔传感器在重力加速度测量实验中的应用 ,同时给出了具体的应用电路     

转小鼠金属硫蛋白(MT)基因烟草不同器官中金属离子铅和锌的分布

转金属硫蛋白(MT)基因植物具有清除重金属污染的能力,但是金属离子在植物体内的分布研究较少。文章以多代培育纯合的转MT烟草为材料,研究了转MT基因烟草积累铅和锌以及铅和锌在不同器官的分布情况。结果表明转基因植株的老叶、茎部和根部铅和锌积累量显著高于普通烟草植株,整株的铅和锌含量分别提高了21.8%和27.2%。铅和锌在植物体内的分布也发生了变化,转基因植株老叶和根中的铅含量分别高出普通烟草同位置的30.2%和47.8%,锌在转基因植株老叶、茎和根中的含量分别高出普通烟草同位置的44.7%,29.2%和21.6%,说明铅更容易在转基因植株老叶和根中积累,而锌更容易在转基因植株的老叶和茎中积累。     

Effect of ausforming temperature and strain on the bainitic transformation kinetics of a low carbon boron steel

The effect of ausforming temperature and strain on the bainitic transformation kinetics was investigated in a low carbon boron steel. A new mechanism, which is based on the competition between the increase in nucleation rate and the decrease in average volume of bainite sheaf after deformation, is proposed. The increase in nucleation rate is due to the decrease in boron concentration at the grain boundaries after small deformation and the formation of sub-grain boundaries at the grain interior after large deformation. The decrease in average volume of bainite sheaf is ascribed to the frequent impingement of bainite sub-units after deformation. The increase in nucleation rate after deformation results in the decrease in incubation time, which is confirmed from the experiment. The increase in nucleation rate overcomes the decrease in average volume of bainite sheaf, resulting in the increase in transformation velocity and volume fraction after small deformation. On the contrary, the decrease in the average volume of bainite sheaf overcomes the increase in nucleation rate after large deformation, leading to the decrease in transformation velocity and volume fraction of bainite.     

石墨狭缝中甲烷吸附的分子动力学模拟

用分子动力学模拟研究石墨狭缝中甲烷的吸附,考察狭缝宽度和温度对甲烷吸附的影响.模拟发现甲烷在石墨狭缝中出现分层现象,吸附层中甲烷具有类液特征,第一吸附层内甲烷中总有两个氢原子的连线与另外两个氢原子的连线分别位于平行于狭缝壁的两个平面内,游离层中甲烷呈现气体的特征;碳原子间的平均作用势说明吸附层中甲烷分子间结合能力大于游离层,吸附态是甲烷在石墨狭缝中的主要赋存形式之一;伦敦力以及由吸附层净电荷产生的电场力是甲烷吸附和分层的主要原因;甲烷的吸附量随狭缝宽度增大或温度升高而减少,当狭缝宽度小于16.46Å时,甲烷仅以吸附形态存在.甲烷在第一吸附层中的扩散能力最弱、游离层中最强,甲烷扩散系数随狭缝宽度的增大或温度的升高而增大.     

火焰原子吸收光谱法测定鸭粪中铜和锌的含量

采用火焰原子吸收光谱法测定白洋淀生态养鸭场中饲料及鸭粪中的铜和锌含量,测定结果为饲料中的铜含量范围在9.7-61.55mg/kg,锌含量范围在63.14-149.07mg/kg,在禽类饲料中铜、锌含量属于较低的类型;鸭粪中铜含量范围在13.71-94.74mg/kg,锌含量范围在156.98-346.31mg/kg,参...     

降雨对无线激光通信的影响

通过激光信号在雨介质中传输的实验发现,在大雨环境下,激光信号透射率要比在小雨或微雨的情况下大。这说明光信号在小雨时衰减较大,在大雨时衰减较小。这一现象与人们通常所认为的有所不同。针对降雨对激光信号的影响,根据Mie散射理论和Weibull雨滴尺寸分布模型,分析了不同尺寸的粒子对光的散射作用以及对衰减效率因子的影响,推导出单球粒子对光波的衰减公式,得到了衰减与降雨率的确定关系。通过数值计算发现,与小粒子相比大粒子的前向散射光强更大且更加集中;激光信号在雨介质中传输时,衰减系数在小雨时较大,中雨、大雨时较小,暴雨时不断增大。这一结果与实际情况较吻合,为激光在通信系统中的应用提供了一定的理论依据。     

Thermodynamically equilibrium roton states of nanoparticles in molten and vapour phases

We show a possibility for a thermodynamically equilibrium nanocrystalline structure consisting of nanosized solid inclusions to appear in a melt just beyond the melting curve. Thermodynamic stability of the nanocrystalline structure in the melt results from the free energy lowering due to rotational motion of nanoparticles. The main contribution to the reduction of the free energy of the system is due to an increase in the rotational entropy and change in formation energy of nanocrystals, i.e. the nanocrystalline structure in the melt, like vacancies in a crystal, is an equilibrium defect structure of the melt. It is demonstrated that similar nanocrystalline structures can also appear in the vapour phase in the form of liquid nanodrops and in liquid solutions, e.g. in He II.     

水溶液中微量Cu元素的激光诱导光谱检测

采用普通打印纸作为基底置于含有痕量重金属离子的水溶液中,用于富集溶液中的重金属Cu元素,烘干后用激光诱导击穿光谱进行定量分析。该方法克服了用激光诱导击穿光谱方法直接分析液相样品中重金属含量时存在水的溅射和灵敏度低等不足。实验中选用324.7 nm的光谱线作为分析线,研究了光谱强度与富集时间的关系,建立了用于溶液中Cu元素定量测量的校正曲线,检测限达到0.023 mg·L-1。为水体中重金属检测提供了一个可行的具有良好灵敏度分析技术。     

Changes in ADC caused by tensile loading of rabbit achilles tendon: evidence for water transport

Water diffusion measurements were performed on rabbit Achilles tendons during static tensile loading and tendons in an unloaded state. The apparent diffusion coefficient (ADC) was measured along two directions: parallel and perpendicular to the long axis of the tendon. Tendons were studied after being prepared in two ways: (a) after being stored frozen in phosphate-buffered saline (PBS) and (b) freshly isolated. Statistically significant directional anisotropy was observed in the ADC in all tendons. The ADC was significantly greater in the direction parallel to the long axis of the tendon than in the perpendicular direction. The anisotropy is attributed to the greater restrictions seen by the water molecules in the perpendicular direction and is consistent with the known geometry of the tendon. Storage in PBS caused tendons to swell. This increased the ADC measured along both directions and reduced the anisotropy. The existence of anisotropy in the ADC was not related to the orientation of the specimen in the magnet. The ADC increased along both directions following the application of a 5-N tensile load; the increase was greatest along the perpendicular axis of the tendon. In order to determine whether load-related changes in the ADC reflected changes in interfibrilar spacing, we used electron microscopy to measure load-related changes in fibril spacing. Load-related changes in fiber spacing could not account for the observed changes in the ADC. The increase in ADC caused by loading was attributed to the extrusion of tendon water into a bulk phase along the outside surface of the tendon. In PBS-stored samples, enough fluid was extruded that it could be visualized. The transient response of the ADC to a 5-N tensile load was also studied. The absolute ADC in both directions increased with loading and recovered to baseline upon unloading. The transient changes in ADC, for both loading and unloading, had a mean time constant of approximately 15 min. The magnitude of the load-induced transient ADC changes was comparable to that seen in the static-loading experiments.     

Preparation of the Speech-LanguagePathologist Specializing in Voice: An Educational Survey

This study investigates the academic and clinical preparation a speech-language pathologist receives in the area of voice. The purpose is to determine how to structure continuing education and specialty training in vocology, defined as the science and practice of voice habilitation. Surveys were sent to the graduate programs in speech-language pathology accredited by the American Speech-Language-Hearing Association (ASHA) in 1994, and again in 1999. Results from the 1994 survey indicated that students received limited information and clinical experience in handling typical voice cases. Although most programs required a voice disorders course, fewer mandated coursework in normal voice production or clinical experience with voice patients. The follow-up survey showed that the educational environment in 1999 is similar to that in 1994. It is evident that the programs are in compliance with the Educational Training Board model developed by ASHA for basic clinical competence, but no structure for specialty training has yet emerged.