Data Aquisition Systems

In this section we will describe two data aquisition systems which are actually used at the storage ring DORIS for experiments on polymers. A detailed description of different data aquisition systems can be found in the article by Hendrix (this Volume). 

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Center of the U.S. Bureau of Mines. The radon chamber in Denver Research Center is designed to provide adjustable humidities and a well controlled, monitored radon and CN concentration. It has a length of 213 cm, a diameter of 152 cm, and a volume of about 3.89 m. The walls are made of 0.5-cm rolled steel with welded seams. Figure 1 shows the general scheme of the test chamber excluding the transducers and data aquisition system. 

A data aquisition system based on a one dimensional, gas filled detector is shown in Fig. 31. The general philosophy of the system is to be as independant as possible from a central computer as the enormous amount of data demand an on line data analysis during the experiment. 

Oriented polymers will no longer show a symmetric scattering pattern. For such systems a two dimensional detector is necessary. A commercial data aquisition system (Westinghouse), based on a Vidicon tube, is shown in Fig. 32. The video signal... 

The discussion will be restricted to the design goals, as related to present research interests. Questions related to heating of optical elements, response of detection systems or data aquisition systems will not be treated. 

Lozano, A., Rosell, J., PaUas-Areny, R., 1995. A multifrequency multichannel electrical impedance data aquisition system for body fluid monitoring. Physiol. Meas. 16, 227—237. 

Fig. 6. Block scheme of the galvanostat with the microcomputer control OA -operational amplifier, R - 1 kQ resistor, SG - pulse generator, DAS - data aquisition system, pC-microcomputer...

DeSa, R. J. Gibson, Q. H. (1969). A practical automatic data aquisition system for stopped-flow spectrophotometry. Computers and Biomedical Research, 2,494-505. 

Rates of emission of SO2, HCl, NOx (nitrogen oxides) and hydrocarbons are measured at the stack and recorded continuously by a computerized data aquisition system in the central operation control room. Dust particles, which may contain residual arsenic, for example, are separated isokinetically from the off-gas by a dust probe and subjected to laboratory analysis by atomic absorption spectroscopy. 

The experimental apparatus consists of eight main parts an ultraviolet flashlamp capable of repetitive flashing at about 5 Hz, a purge flow reactor with either pinhole or molecular beam sampling, an ion source, a mass filter, an ion detector, pulse-counting electronics, computer data aquisition, and a vacuum system. A diagram of the apparatus is shown in Figure 1. 

Application of laser Raman multichannel spectroscopy to a kinetic investigation in the liquid phase has been reported by Crunelle-Cras and Merlin (1977). A multichannel spectrometer with photoelectric image devices, interfaced with a data aquisition and handling system, permits the study of fast processes, exemplified by the fast oxidation of the sulfite ion by the bromate ion in an acidic medium. 

The DSC impurity analysis is described in USP. With modern equipment including robotic systems and data aquisition, the DSC purity analysis is a state-of-the-art technique for pharmaceutical development. 

Gas Chromatograph Hach/Carle AGC Series 400, Model 04192-A Data Aquisition Peikin-Elmer Sigma 15 Chromatography Data System Sample Handling Vacuum manifold with Validyne Model CD 223 Digital Manometer. 

Sample disk rotation system Repxate I kHz Speed 50mm/s Side-run out <2 pm Data aquisition for a disk 1.8 M ts Aquisition time 30 min... 

A weight or load is applied to the dumb-bell by way of a lever system [26]. The small extensions to be measured will require a very sensitive extensometer to be used. Extensometers based on the optical lever principle have been widely used but those based on Moire fringes or on displacement transducers are more suitable for data aquisition by microcomputer. Over this long period of testing, stress must be maintained to an accuracy of better than 1% and no electrical or thermal drift must occur in the extensometer [26]. 

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