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1.
We present the AS-2 Attosecond Beamline at the Joint Laboratory for Attosecond Physics of the Max-Planck-Institut fu?r Quantenoptik and Ludwig-Maximilians-Universita?t for time resolved pump/probe experiments with attosecond resolution. High harmonic generation and subsequent filtering of the generated extreme ultraviolet (XUV) continuum by means of metal filters and XUV multilayer mirrors serve for the generation of isolated attosecond laser pulses. After high harmonic generation, the remaining fundamental laser pulse is spatially separated from the attosecond XUV pulse, to what is to our knowledge for the first time, by means of a perforated mirror in a Mach-Zehnder interferometer. Active stabilization of this interferometer guarantees the necessary temporal resolution for tracking attosecond dynamics in real time. As a proof-of-principle, photoelectron streaking experiments are performed and experimental techniques for their realization are summarized. Finally we highlight the potential of the presented beamline system for future experiments in comparison with previously demonstrated attosecond beamlines.  相似文献   

2.
This paper presents a new type of cold atom interferometry gravimeter based on Bragg diffraction,w hich is able to increase the gravity m easurem ent sensitivity and stability of com m on Ram an atom gravim eters significantly. By com paring w ith Ram an transition,the principles and advantages of Bragg diffraction-based atom gravim eters have been introduced. The theoretical m odel for a tim e-dom ain Bragg atom gravim eter has been constructed. Som e key technical requirem ents for an n-order Bragg diffraction-based atom gravim eter have been deduced,including the tem perature of atom cloud,the diam eter,curvature radius,frequency,intensity,and tim ing sequence of Bragg lasers,etc. The analysis results are verified by the existing experim ental data in discussion. The present study provides a good reference for the understanding and construction of a Bragg atom gravim eter.  相似文献   

3.
VXI多插板式平台(VXI Versatile Plug-in,VVP)结构是一种创新的通用VXI模块结构。该平台的硬件部分为C尺寸大小的VXI模块,集成了用FPGA实现的VXI-VVP接口控制器、功能强大的DSP、前面板I/O装置、电源供给管理电路和其它一些通用的功能电路,可同时搭地四个功能贴板。在硬件平台的基础上建构的平台管理软件类似于一个简单的操作系统。在该软硬件平台上设计各种用途的贴板,可以方便高效地搭建从高端到低端的各种寄存器基VXI仪器模块,从而有效地简化了VXI模块的设计。该平台并且具有低成本和高性价比的优点。  相似文献   

4.
5.
DFR控制的A10VO系列柱塞泵能实现多种功能,该文介绍了几种常用功能及其工作原理。  相似文献   

6.
介绍了一种多用途结构光传感器,它具有结构简单、使用方便、抗干扰、非接触、对被测表面没严格要求等特点,特别适合于对移动物体和腐蚀性表面的快速、在线、非接触测量,具有广泛的应用前景  相似文献   

7.
尤政  胡庆英 《工具技术》1996,30(12):35-36
本文介绍了一种多用途结构光传感器,它具有结构简单、使用方使、抗干扰、非接触测量、对被测表面无严格要求等特点,特别适合于对移动物体和腐蚀性表面的快速、在线、非接触测量.具有广泛的应用前景。  相似文献   

8.
本文通过对晶体二极管的典型应用和变通应用的分析,提出了晶体二极管的变通应用方法,为电子工程技术人员掌握晶体二极管的变通应用提供了一种有效解决途径。  相似文献   

9.
The design of a four-probe ac conductivity measurement system is described. The system is capable of making precision conductance measurements from 10(-8) to 10(-5) S at 20 to 200 Hz. Driven coaxial shields and a controlled current source are utilized to eliminate phase shift/attenuation errors, and make the measurement of conductances on a variety of materials a routine procedure requiring a minimum of operator intervention.  相似文献   

10.
11.
An electron spectrometer is described which is designed to measure a variety of electron spectra of solid surfaces in ultrahigh vacuum. The instrument is capable of the high-energy resolution (10-15 meV) required for vibrational inelastic electron scattering from atoms and molecules on surfaces. It has also been designed to carry out angle-resolved photoemission measurements, Auger electron spectroscopy, and energy-loss measurements of electronic excitations. The performance of the instrument in these modes of operation is discussed.  相似文献   

12.
本文介绍一种恒温加热器的设计与开发.系统以单片机为核心.可以适用于各种需要恒定温控的场合.数码管可以显示出水温温度和设置的水温参数.单片机能根据现场水箱的温度信号及上.下水位限信号,自动地控制其冷水阀的开启进行加水.控制加热器的开关得到恒温水。  相似文献   

13.
分析了限制传统金属探测器精度和应用的因素,阐述了一种感应式金属探测器的工作原理,在此基础上,提出一种数字式多功能金属探测器的实现方案,设计了以Atmel微控制器为核心处理器的嵌入式计算机系统,该系统不但能够检测金属,还可确定金属的形状、大小等信息,可用于加工、生产过程中的金属检测,也可用作便携式检测设备.  相似文献   

14.
对传统的台虎钳进行改造,使之可以在水平和竖直两个方向上方便、稳定的转动;同时采用开合螺母,利用其结构简单、快速开合的优点,实现活动钳身的快速移动,从而使该夹具能够快速适应不同结构、不同大小的工件的装夹,以实现高效、多功能、低成本的目的。  相似文献   

15.
ABSTRACT

A computer-driven pump controller capable of providing voltage, current and pulsed outputs for up to five pumps in analytical systems is described. The controller is ideal for situations which require remote control of speed and direction for many pumps of different types. The design is based on the Advanced Micro Devices 9513 system timer chip and provides 0-10 V, 0-25 mA and pulsed TTL outputs to control each pump. In addition, phase-locked loop circuitry allows feedback for speed regulation of certain pumps. For control of stop/start, direction or other functions, eight independently programmable TTL outputs are provided. The controller is inexpensive and designed to be driven from the parallel printer port of an IBM PC compatible computer for maximum portability. Other uses of the interface are also possible.  相似文献   

16.
A miniature diamond anvil high-pressure cell 42 mm in diameter, 18 mm thick, and 150 g in weight has been constructed. The cell is loaded into a piston-cylinder type pressing device with an alignment mechanism and compressed to a desired pressure. After the pressure is clamped by three screws, the cell part is taken out. Thereby, in spite of the small and simple cell, pressure can be generated easily and steadily up to 200 kbar. Because the cell is small and light enough to be mounted on a usual goniometer head, and has large openings towards both the top and bottom, it can widely be used as a versatile apparatus for research at high pressure.  相似文献   

17.
Abstract

Data acquisition is reported for a Varian CP 3800 gas chromatograph with affordable and user friendly interface box and software. LabPro was triggered to commence data acquisition upon sample injection and simultaneously monitored two detectors and oven temperature. After acquisition, functions are available for determining the retention time and for peak integration after baseline subtraction. Data may be exported as a text file. The interface box and software are available at a tenth of the cost of the instrument vendor's software. In this work, the determination of optimum carrier gas flow rate is reported as an example.  相似文献   

18.
19.
SUMMARY

A signal generator has been designed to produce precise triangular waves and a variety of ramp-and-hold signals. The circuit involves a network of Zener diodes and two conventional operational amplifier circuits. An externally generated ramp voltage is required and can be obtained from either an operational amplifier integrator or the sweep generator from a cathode ray oscilloscope. The ramp-and-hold signals have been proven to be extremely useful in stationary electrode polarography, especially when dealing with multicomponent system and complex reaction mechanisms. Triangular waves with scan periods from about 150 sec to less than 1 msec can be produced and a potential “hold” can be obtained at any desired point.  相似文献   

20.
ABSTRACT

A versatile potentiostat which can supply a maximum of 125 ma is described. The potentiostat uses readily available electronic components and an interface is detailed which allows the potentiostat optional computer control.  相似文献   

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