Electronic data acquisition systems

A portable electronic data acquisition system was transported to the plant site and connected to the extruder panel. All available instrument outputs from the panel were connected in parallel with the acquisition system. Data collected included barrel zone temperatures, screw speed, motor current, pressure at the entry to the pump, transfer line temperature, and gear pump temperature. Process data were collected at a frequency of once every five seconds. 

Basically, the LC instrument is made of solvent reservoirs, pumps, an injection device, a detector, and a data acquisition system (Fig. 14). It must be kept in mind that two solutes cannot be electronically resolved. 

Control System Included in this classification are Supervisory Control and Data Acquisition Systems (SCADA), Distributed Control Systems (DCS), Statistical Process Control systems (SPC), Programmable Logic Controllers (PLCs), intelligent electronic devices, and computer systems that control manufacturing equipment or receive data directly from manufacturing equipment PLCs. 

Figure 3. Schematic of turbulent combustor geometry and optical data acquisition system for vibrational Raman-scattering temperature measurements using SAS intensity ratios. Also shown are sketches of the expected Raman contours viewed by each of the photomultiplier detectors, the temperature calibration curve, and several expected pdf s of temperature at different flame radial positions. The actual SAS temperature calibration curve was calculated theoretically to within a constant factor. This constant, which accounted for the optical and electronic system sensitivities, was determined experimentally by means of SAS measurements made on a premixed laminar flame of known temperature. Measurements of Ne concentration were made also with this apparatus, based on the integrated Stokes vibrational Q-branch intensities. These signals were related to gas densities by calibration against ambient air signals.

Our processing is much better now, and we can get the properties right so they re reproducible. We know enough about the process and the conditions, and so we can always get to reasonable quality with 95 K materials. We have a lot more instrumentation now to do things that we had done by just pure happenstance. We ve put eyes into the ceramists methods. We put a resistor, say, into it so that as you go up and down the temperature scale, you monitor the differences as you see them, and that s called differential thermal analysis. Once the ceramists make the stuff, we go to an electron microscope and see what that little glitch means insofar as the microstructure is concerned. We go to the data acquisition system, the computer, and find out where the atoms are, what the crystal structure is, and we ask, Did the electrons go the wrong way ... 

Since particles in the micron and submicron size range are of primary importance, the emphasis in this study is on using the singleparticle light scattering characteristics, and a new optical single-particle ratio counter was improved and calibrated. Furthermore, an electronic data acquisition system was developed, and finally the counter was applied to an in situ, real time study of automobile exhaust gas analysis. 

Electronic Data Acquisition System. Essential for the eflFective use of a MRSPC is an electronic data acquisition system that can interface directly with the photomultipler tubes and automatically detect the particles, calculate the ratios, and store the results. The function of the interface can be divided in two main parts ... 

A stirred cell equipped with a 0.22iuni membrane filter was charged with 30 mL of latex, the dispersion of microsphere. The specific surfrice area was adjusted to 0.19 m per ImL and the ionic strength was calibrated to 0.01. At the constant stirrer speed, buffer solution was introduced into the stirred ceil until steady state flux was attained. Protein solutions were introduced with step of pulse injection. The permeate flux was measured continuously with an electronic balance (Precision plus, Ohaus Co., USA) by a data acquisition system. The electronic balance was connected to a PC through a RS 232C interfece. The surface charge density of microspheres was varied as 0.45, S.94, 9.14 and 10.25, and the stirrer speed was varied as 300,400 and 600rpm. 

Figure 26-F1 Instrument diagram for a basic FTIR spectrometer. Radiation of all frequencies from the IR source is reflected into the interferometer where it is modulated by the moving mirror on the left. The modulated radiation is then reflected from the two mirrors on the right through the sample in the compartment at the bottom. After passing through the sample, the radiation falls on the detector. A data acquisition system attached to the detector records the signal and stores it in the memory of a computer as an interferogram. (Courtesy of Thermo Electron Corp., Madison, WI. With permission).

Spectra. The energy spectrum is collected from the particles emitted from all depths simultaneously using a silicon surface barrier detector, electronic amplifiers, an analog-to-digital converter and a multichannel analyzer. A reference pulse is fed into the electronics to monitor the stability of the system thus allowing corrections to be made should electronic drift occur during the course of the measurement. Specific systems are described in the references (1 -4,6,7,12-17). By using computer-based data acquisition systems, the depth profile can be displayed at the time of analysis. 

Figure 8. Block diagram of electronics used to couple the PARC photodiode array readout electronics to a local data acquisition system. (Reproduced with permission from Ref. 12. Copyright 1982, Appl. OpticsJ...

The research for chemosensors began as a branch of analytical chemistry and is now an approved and independent field of activities at the interface between research and application. A chemosensor can be considered as a small unit for the acquisition of analytical data. It has been optimized for one distinct application includes a sensitive layer, whose physico-chemical properties are affected by the interaction with the substance to be detected. These effects are translated into electronic signals by microelectronic devices and can be processed by data acquisition systems [11]. In most cases, mass-sensitive or optical transducers are used, and some of them are listed in Table 10.1. 

Recombined oil (also referred to as live oil ) was prepared by saturating the oil with methane gas in recombination equipment connected to the inlet end of the core holder. Produced fluids were collected into a graduated cylinder placed on an electronic balance for measuring the oil production rate. An automated data acquisition system was employed for recording of the oil-production rate and the differential pressures in each segment during the flow experiment... 

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