Computerized data acquisition system

The DBMS setup and experimental procedures used in this study were the same as described in more detail elsewhere [Jusys et al., 2001]. Briefly, the DBMS setup consisted of two differentially pumped chambers, a Balzers QMS 112 quadrupole mass spectrometer (MS), a Pine Instruments potentiostat, and a computerized data acquisition system. 

Given the subjective nature of recognizing clinical signs, careful steps must be taken to ensure uniformity (is the animal depressed or prostrated ) of observation so that the data can be analyzed in a meaningful fashion. There are three ways of achieving this. First, signs should be restricted to a predefined list of simple descriptive terms, such as those listed in Table 5.4 or in Appendix B. Second, if a computerized data acquisition system is unavailable, the use of standardized forms will add uniformity to the observation and recording processes. An example of such... 

Electrochemical calorimetry — is the application of calorimetry to thermally characterize electrochemical systems. It includes several methods to investigate, for instances, thermal effects in batteries and to determine the -> molar electrochemical Peltier heat. Instrumentation for electrochemical calorimetric studies includes a calorimeter to establish the relationship between the amount of heat released or absorbed with other electrochemical variables, while an electrochemical reaction is taking place. Electrochemical calorimeters are usually tailor-made for a specific electrochemical system and must be well suited for a wide range of operation temperatures and the evaluation of the heat generation rate of the process. Electrochemical calorimeter components include a power supply, a device to control charge and discharge processes, ammeter and voltmeter to measure the current and voltage, as well as a computerized data acquisition system [i]. In situ calorimetry also has been developed for voltammetry of immobilized particles [ii,iii]. 

First, either by visual reading or by computerized data acquisition system, read off the coordinates of ad and y corresponding to each other. Since y is controlled to the sine form of Equation 1, it is easy to determine the phase angle difference 8 (0) between ad and y as defined by ... 

A schematic diagram of the computerized data-acquisition system is given in Figure 23.35. The computer initiates the data-acquisition cycle by executing a COMMAND instruction this terminal goes to a 1 state and is connected to the ENABLE input of a 10-kHz clock, the output of which enables a 10-bit ADC every... 

The earliest work in high-resolution mass spectrometry produced spectra similar in appearance to that in Figure 3.3a. Chart records were obtained by slowly varying the magnetic field of a Nier-Johnson mass spectrometer. The time (or distance along the chart) between the centers of unknown and reference peaks and the known reference masses was used to determine the exact masses of the unknown ions. Current instruments, with their computerized data acquisition systems, automatically identify the reference masses, generate the internal calibration table, and calculate the accurate masses. 

The circuit shown in Figure 3-7 provides a convenient means for measurement of the resistance or conductance of a transducer. Here, a constant voltage source is used for K and the transducer is substituted for either ff, or R, in the circuit. The amplified output voltage v, is then measured with a suitable meter, potentiometer, or a computerized data-acquisition system. Thus, if the transducer is substituted tor R( in Figure 3-7. the output, as can be seen from rearrangement of Equation 3-8, is... 

Garland [10] developed an a.c. calorimeter technique for the study of second-order phase transitions. The device works up to 300 MPa and requires only a small sample (50-100 mg). In [10] two versions of this calorimeter are described a manually operated calorimeter with a computerized data-acquisition system, and a fully computerized calorimeter which can work in a scanning mode. 

Data Acquisition System—Use any integrator or computerized data acquisition system for peak area integration, as well as for recording the chromatographic trace. 

The measurements were carried out in a modified Sofica apparatus equipped with a HeNe-laser and a computerized data acquisition system. It was calibrated against a toluene standard. The cuvette was rotated to several positions and an ensemble average of scattering intensity was taken to account for the fixed structure of the gels. 

---