用迈克尔逊干涉仪测量金属的线膨胀系数

将迈克尔逊干涉仪的精确测量和金属线膨胀系数的PID温度控制测量方法相结合,被测金属样品被加热后会发生长度的变化,从带动镜面产生微小移动,进而引起迈克尔逊光路中两束光的光程差的改变,通过干涉条纹记录温度变化时干涉条纹的变化数量,以实现对金属热胀系数的精确测量。     

单缝衍射法测量金属棒杨氏模量的实验研究

介绍了一个用单缝衍射法测量金属棒杨氏模量的综合性实验, 实验中对测量金属棒杨氏模量的传统实 验装置进行了改进, 用单缝衍射法测量微小变化长度, 从而提高了实验的测量精度, 降低了实验误差     

基于调制相移法的高准确度光纤长度测量技术

为了克服传统调制相移法测量频率范围窄、测量准确度低的缺点,提出一种基于调制相移法的单模光纤长度精确测量技术.利用一体化矢量网络分析仪的高速调制信号同步技术及高频信号相位差测量技术,设计并研制了单模光纤长度测量装置.基于矢量网络分析仪自带的VBA插件编写了自动控制及数据处理软件,给出了相位变化量自动处理方法.利用研制的装置分别测量了长度为2km、40km和150km的单模光纤在不同工作波长点的长度值,实验结果表明,2km的光纤长度测量值实验标准偏差优于0.2mm,150km的光纤长度测量值实验标准偏差接近0.01m.该装置可对1 310nm、1 490nm以及1 550nm波长的光纤距离进行精确测量,为光纤长度的高准确度测量提供了一种新的技术途径.     

瑞利临界角的相位法测量

本文根据声波在液体内传播到液-固介质界面上,在入射角为瑞利临界角附近时,反射波有位相π变化的特点,提出了测量瑞利临界角的相位法,并进行了实验观察。这种方法可以用来精确测量固体声表面波的相速度和检测固体中横波相速度的微小变化.     

基于智能手机外设传感器的冷却法测量金属比热容

金属比热容测量的传统方法是冷却法,用此方法通常需要手动控制秒表测量金属的降温时间从而引入较大的误差.为了克服该方法的弊端,采用外设温度传感器通过蓝牙连接智能手机,实时采集金属的降温曲线,实现对降温时间的精确测量.该方法不仅避免了人工控制秒表测量时间的误差,同时还能得到温度随时间下降的连续曲线,方便调入Origin软件对数据进行拟合和计算.实验研究表明：该实验结果与标准值符合得很好.     

光杠杆法测定金属线胀系数实验分析

在不增加任何实验装置和改变测温系统的条件下,采用降温测量的方法测定了金属线胀系数。比较了升温测量和降温测量的实验结果,并对测量进行了误差分析。结果显示降温测量能有效地解决了升温测量结果偏差太大的问题。     

使用四象限探测器测量微小位移

四象限探测器的工作原理是光生伏特效应,通过4个象限电势的变化可算出光源的位移.使用四象限探测器测量了光源横向和纵向的位移,分析了实验误差的来源并给出了修正方法.实验结果表明,四象限探测器测量位移具有较高的测量精度和较短的时间响应,纵向测量的灵敏度比横向测量的灵敏度低.     

PN结正向压降与温度关系实验的讨论

本文研究了PN结正向电压与温度关系实验中升温和降温、不同的升温速度对PN结正向电压的影响,实验发现：降温测量的不确定度小于升温测量结果.     

动态双光栅测量金属热膨胀系数

在双光栅测量音叉微小振幅的理论基础上,利用静光栅纵向位移对金属热膨胀系数进行测量.本文给出了动态双光栅测量金属热膨胀系数的理论拓展与实验结果.     

弹性模量千分表测量方法的建立

为建立一种借助千分表测量杨氏弹性模量高精度的方法,本研究通过千分表精准测量样品受力后其微小长度变化量,进而测得其杨氏弹性模量。对所测的数据经计算分析,结果表明该方法精度高,测量结果可靠。与光杠杆法测量样品微小长度这一传统方法相比,仪器构造简单,实验现象直观,操作简便。     

关于"太阳在银河系中所受引力与到银心距离r的关系"的讨论

讨论了银道面内的引力场强分布和太阳在银河系中所受引力与到银心距离r的关系，指出引力场强g并不是与r的平方成反比，这是由于银河系的大小和形状不能忽略造成的．强调了万有引力定律的适用条件．     

Set the controls for the heart of the Sun

In this paper we describe experiments conducted with high-power lasers that are attempting to replicate, for a very short time and in miniature, conditions found in the Sun. Experiments to date have reached conditions in the outer part of the Sun. To reach the Sun's centre requires compression of material to very much greater than solid density and heating to over ten million degrees. To achieve this, a new class of experiments and a new generation of high-power lasers are required.     

Dependence of the Intensity of the Spectral Lines and the Composition of the Sample and the Plasma Parameters of the Unipolar Arc

The investigation was made of the dependence of the intensity of Tl, Ga, Mo, Mg, Mn, Sn, Bi, Ni, Zn, Pt and Au spectral lines and the plasma parameters (temperature T, electron concentration n_e, degree of 6 ionnization α) from concentration of lithium additive.     

干涉仪系统传递函数测量及影响因素的分析

波前功率谱密度(PSD)被用于评价惯性约束聚变(ICF)激光驱动器光学元件中频段的波前误差。干涉仪对PSD较高空间频率分量的测量存在失真效应,可通过干涉仪系统传递函数(STF)的检测标定来获得真实的波前PSD分布。采用台阶板位相比较法测得大口径菲索相移干涉仪检测系统在透射和反射检测情形下的传递函数。对传递函数测试算法进行了比较分析,明确了干涉仪系统zoom倍率的改变等因素对传递函数测量的影响,为波前PSD的准确检测奠定了基础。     

From the Solution of the Tsarev System to the Solution of the Whitham Equations

We study the Cauchy problem for the Whitham modulation equations for increasing smooth initial data. The Whitham equations are a collection of one-dimensional quasi-linear hyperbolic systems. This collection of systems is enumerated by the genus g=0,1,2, ... of the corresponding hyperelliptic Riemann surface. Each of these systems can be integrated by the so-called hodograph transformation introduced by Tsarev. A key step in the integration process is the solution of the Tsarev linear overdetermined system. For each g>0, we construct the unique solution of the Tsarev system, which matches the genus g+1 and g–1 solutions on the transition boundaries.     

On the Problem of the Amenability of the Gauge Group

Let G be one of the local gauge groups C(X, U(n)),C (X, U(n)), C(X, SU(n)) or C (X, SU(n)) where X is a compact Riemannian manifold. We observe that G has a nontrivial group topology, coarser than its natural topology, w.r.t. which it is amenable, viz. the relative weak topology of C(X, M(n)). This topology seems more useful than other known amenable topologies for G. We construct a simple fermionic model containing an action of G, continuous w.r.t. this amenable topology.     

On the stability of the equilibria of the Rikitake system

In this note we present an analytical study of the stability of the equilibria of the Rikitake system. We prove that the two non-hyperbolic equilibria of the Rikitake system are unstable for all positive values of the parameters.     

Testing the mechanism for the LSP stability at the LHC

The lightest supersymmetric particle (LSP) is a natural candidate for the cold dark matter of the universe. In this Letter we discuss how to test the mechanism responsible for the LSP stability at the LHC. We note that if R-parity is conserved dynamically one should expect a Higgs boson which decays mainly into two right-handed neutrinos (a “leptonic” Higgs) or into two sfermions. The first case could exhibit spectacular lepton number violating signals with four secondary vertices due to the long-lived nature of right-handed neutrinos. These signals, together with the standard channels for the discovery of SUSY, could help to establish the underlying theory at the TeV scale.     

地球的扁率对卫星运动的影响

指导出地球引力场的势能,分析了卫星的椭圆轨道旋进的现象。