7502B光电直读光谱仪计算机升级

对国产７５０２Ｂ型ＩＣＰ光电直读光谱光谱仪的计算机控制系统的软硬件结构及其基本运行原理进行了分析，叙述了将其原有主控制计算机从长城０５２０ＣＨ－Ⅱ型微机升级为ＩＢＭＰＣ兼容奔腾机所存在的软件，硬件方面的问题及其解决办法。     

微机串行通信波特率的设置

本文以ＩＢＭ—ＰＣ机与ＭＣＳ—５１单片机间的串行数据通信为例，分析了波特率对微机串行通信的影响，讨论了微机串行通信彼特率的设置方法．     

组合数学方法推引原子谱项（Ⅲ）非等效组态的谱项及其微机处理

讨论了推引非等效组态原子谱项的组合数学方法和矢量加和法，并编制了ＢＡＳＩＣ语言程序，在微机上快速推求非等效组态的谱项。     

组合数学方法推引原子谱项（Ⅱ）：等效组态谱项的微机处理

运用组合数学方法编制ＢＡＳＩＣ语言程序在ＡＳＴ－２８６计算机上推出等价电子组态的原子谱项，能迅速准确地得出结果。计算具有４８６２０个微状态的ｇ９组态，只需６秒钟便能得出全部１０１７个谱项，对尸组态的计算仅需３秒钟。该程序在微机上计算的电子能态ｌ可高达５３。     

利用IBM微机辅助物理实验的设计

本文介绍利用ＩＢＭ微型机进行中专物理实验的一种科学准确的设计方法，利用微机对实验对象进行实时地数据采集和处理，学生测得的原始数据或实验结果跟计算机的数据相比较，可得出误差，误差太大，计算机要求重做，本文以测加速度实验为例，说明本实验的结构可以进行许多力学实验及光学实验．     

ER－200D－SRC型EPR谱仪微机系统的改造

详细叙述了德国ＢＲＵＫＥＲ分析仪器公司ＥＲ－２００Ｄ－ＳＲＣ型ＥＰＲ谱仪与ＩＢＭＰＣ／３８６微机联机的软硬件系统，该系统综合了仪器的自动磁场扫描控制，数据采集累加和数据分析处理及数据绘图、打印等各项功能。其硬件由ＩＢＭＰＣ／３８６微机及二大接口模块组成。一块为商品化的１２位Ａ／Ｄ、Ｄ／Ａ接口卡，另一块为自行设计的以ＩＮＴＥＬ－８２５５可编程通用接口电路为主体的数字量输入输出控制接口卡，可分别独立地插入ＰＣ机的扩展槽中，其软件采用Ｃ语言编写，具有菜单式、结构化、模块化、汉字工作提示、实验数据实时屏幕绘图、实验参数实时显示等特点，用户界面良好，该系统恢复并提高了原谱仪的整体性能，具有一定的推广价值。     

组合数学方法推引原子谱项（II）：等效组态谱项的微机处理

运用组合数学方法编制ＢＡＳＩＣ语言程序的ＡＳＴ－２８６计算机上出等价电子组态的原子谱项，能迅速准确地得结果，计算具有４８６２０个微状态的ｇ＾９组态，只需６秒钟便能得出全部１０１７个谱项，对ｆ组态的计算仅需３秒钟，该程序在微机上计算的电子能态Ｌ可高达５３。     

微机控制的CARS实验装置及三氯甲烷的CARS谱

用 ＡＰＰＬＢ ＩＩ微机实现了包括激光触发，波长调谐，相位匹配角计算和调整，探测波长自动跟踪以及数据采集和处理等过程的ＣＡＲＳ（相干反斯托克斯拉曼散射）实验目动化．给出了三氯甲烷的ＣＡＲＳ谱，证明了装置的可靠性．     

基于符号替换算法的光电混合型计算机的设计

在分析符号替换算法特点的基础上，提出了基于此算法的光电混合型计算机ＯＥＨＣＢＳＳ的体系结构及其算法。性能分析表明ＯＥＨＣＢＳＳ可实现性强、性能优，特别是其光符号替换处理器具有通用性强、速度快等特点。     

Excel在物理实验室

Ｅｘｃｅｌ在物理实验室何军（军械工程学院理化教研室石家庄０５０００３）１背景我们将微机引入物理实验室已有近１０年的历史，最早采用的是ＩＢＭＰＣ机，取得了较好的效果．由于微机一直在ＤＯＳ下操作，编程繁杂，图形功能差，容量和速度都满足不了实际需求．Ｗｉｎ...     

Direct measurement of group dispersion of optical components using white-light spectral interferometry

We present a simple white-light spectral interferometric technique employing a low-resolution spectrometer for a direct measurement of the group dispersion of optical components over a wide wavelength range. The technique utilizes an unbalanced Mach-Zehnder interferometer with a component under test inserted in one arm and the other arm with adjustable path length. We record a series of spectral interferograms to measure the equalization wavelength as a function of the path length difference. We measure the absolute group refractive index as a function of wavelength for a quartz crystal of known thickness and the relative one for optical fiber. In the latter case we use a microscope objective in front and a lens behind the fiber and subtract their group dispersion, which is measured by a technique of tandem interferometry including also a Michelson interferometer.     

Spectral resolution in a Rickart comgroup

A comgroup is a compressible group with the general comparability property. A comgroupwith the Rickart projection property is called a Rickart comgroup. We show that each element of a Rickart comgroup has a rational spectral resolution and a nonempty closed and bounded (real) spectrum. The rational spectral resolution and the spectrum are shown to have many of the properties of the spectral resolution and spectrum of a self-adjoint operator on a Hilbert space. Examples of Rickart comgroups include the additive group of self-adjoint elements in a von Neumann algebra and the Mundici group of a Heyting MV algebra.     

Electromagnetically induced transparency and light slowdown for Λ-like systems with a structured continuum

Electric susceptibility of a laser-dressed atomic medium is calculated for a model Λ-like system including two lower states and a continuum structured by a presence of an autoionizing state or a continuum with a laser-induced structure. Depending on the strength of a control field, it is possible to obtain a significant reduction of the light velocity in a narrow frequency window in the conditions of a small absorption. It is shown that increasing the values of the asymmetry parameters leads to an increase of the values of both real and imaginary parts of the medium susceptibility and to an increase of the width of the transparency window, compared with the case of a flat continuum. A smooth transition is shown between the case of a flat continuum and that of a discrete state serving as the upper state of a Λ system.     

The Klein-Gordon and the Dirac Oscillators in a Noncommutative Space

We study the Dirac and the Klein-Gordon oscillators in a noncommutative space. It is shown that the Klein-Gordon oscillator in a noncommutative space has a similar behaviour to the dynamics of a particle in a commutative space and in a constant magnetic field. The Dirac oscillator in a noncommutative space has a similar equation to the equation of motion for a relativistic fermion in a commutative space and in a magnetic field, however a new exotic term appears, which implies that a charged fermion in a noncommutative space has an electric dipole moment.     

Letter: Irreversible Processes in a Universe Modelled as a Mixture of a Chaplygin Gas and Radiation

The evolution of a Universe modelled as a mixture of a Chaplygin gas and radiation is determined by taking into account irreversible processes. This mixture could interpolate periods of a radiation dominated, a matter dominated and a cosmological constant dominated Universe. The results of a Universe modelled by this mixture are compared with the results of a mixture whose constituents are radiation and quintessence. Among other results it is shown that: (a) for both models there exists a period of a past deceleration with a present acceleration; (b) the slope of the acceleration of the Universe modelled as a mixture of a Chaplygin gas with radiation is more pronounced than that modelled as a mixture of quintessence and radiation; (c) the energy density of the Chaplygin gas tends to a constant value at earlier times than the energy density of quintessence does; (d) the energy density of radiation for both mixtures coincide and decay more rapidly than the energy densities of the Chaplygin gas and of quintessence.     

污染气体扫描成像红外被动遥测技术研究

傅里叶变换红外光谱技术可实现大气中污染气体的远程被动遥测。而污染气团的位置和分布,对于有害气体泄露情况下泄露位置勘查和污染扩散态势的评估来说是至关重要的。据此设计了一套红外被动成像遥测系统,系统由傅里叶变换光谱仪、数据采集处理软件、扫描系统、可见光成像系统和计算机组成。以六氟化硫为示踪气体,开展了遥测验证实验。通过非线性最小二乘算法结合辐射传输计算反演获得了目标气体的柱浓度,并用伪彩色图显示其分布情况,最后以可见光图像叠加伪彩色柱浓度分布图的形式显示结果。实验分析表明,该系统具有高探测灵敏度,并以可视化和定量的方式显示污染的空间分布情况。     

Spectral-domain intermodal interference under general measurement conditions

Spectral-domain intermodal interference is analysed theoretically at the output of a few-mode optical fibre alone and at the output of the optical fibre in a tandem configuration with a Michelson interferometer. The theoretical analysis is performed under general measurement conditions when a light source of a given spectral bandwidth and a spectrometer of a given spectral bandpass are considered and when first- and second-order intermodal dispersion effects in the optical fibre are taken into account. Thus, the effect of a variable spectral bandpass of a low-resolution spectrometer on the spectral fringe visibility functions for a two-mode optical fibre of known intermodal dispersion is specified.     

Modelling of a closed two-dimensional reactor bounded by a wavy wall

In this paper, we propose a model for a two-dimensional closed reactor bounded by a wavy wall. The left, right and top walls of the reactor are assumed to be flat surfaces while the bottom wall is a wavy surface. In order to formulate a model for such a reactor, we introduce a coordinate transformation into the dimensionless equations of a rectangular closed domain. Then the resulting equations illustrate the phenomena for a closed reactor bounded by a wavy wall. We solve these equations using the finite difference method. The astonishing results are that the intensity of streamlines and the maximum temperature within the reactor significantly increase with an increase of the number of waves in the bottom wall, the amplitude of waves and the Frank-Kamenetskii number. Converse characteristics are observed for higher values of the enlargement of a wave. Moreover, larger Rayleigh number induces stronger vortices in the flow field and reduces the maximum temperature. The Nusselt number at the bottom wavy wall is found to increase for higher values of the Frank-Kamenetskii number and the amplitude of a wave. A transition from the steady-state to the oscillatory convection is identified for a certain value of the Frank-Kamenetskii number. However, for a low value of the Rayleigh number, there occurs a transition from the steady-state to an explosion for increasing value of the Frank-Kamenetskii number. Results also demonstrate that the critical value of the Frank-Kamenetskii number, for which a transition from the steady-state to the oscillatory convection occurs, is higher for increasing values of the number of waves, the enlargement of a wave and the amplitude of a wave.     

Frequency multiplication using induced dipole domains in a semiconductor superlattice

We theoretically studied the possibility of frequency multiplication using propagating dipole domains which are induced in a semiconductor superlattice by microwave radiation. We have investigated the dynamics of electrons in a superlattice submitted to both a static voltage and a microwave field by performing a simulation based on a drift-diffusion model and incorporating current-limiting boundary conditions. The motion of electrons in the superlattice was governed by an Esaki–Tsu drift velocity field characteristic with a negative differential mobility above a critical electrical field. The simulation delivered, for a static voltage larger than a critical voltage, the periodic formation and annihilation of propagating dipole domains and, as a consequence, a reduction of the direct current through the superlattice. Our simulation showed that an additional microwave field can periodically induce and subsequently quench domains giving rise to a strongly anharmonic current. The anharmonicity of the current is the origin for the generation of higher harmonics of the microwave field. Both the formation and annihilation of a domain can take place within a time of about 1 ps suggesting that the mechanism of domain induction and quenching can be used for generation of radiation up to almost 1 THz.