Calibration and adjustment

A thermobalance measures the sample mass as a function of sample temperature. It follows that the user must make sure that the mass and temperature values measured are in fact correct. This is done through frequent checking using a suitable reference sample (determining the deviation of a measured value with respect to the known true value). If the deviation is 

The balance is checked and adjusted using reference masses. Some TGAs are automatically adjusted with built-in reference masses when switched on and diuing longer periods of inactivity. 

A number of international standard test methods exist for TCA and these are listed below  

E1131 -03 Standard Test Method for Compositional Analysis by Thermogravimetry E1582-04 Standard Practice for Calibration of Temperature Scale for Thermogravimetry E1641-04 Standard Test Method for Decomposition Kinetics by Thermogravimetry 

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Calibrating and adjusting devices against certified equipment (4.11.2b)... 

The standard requires the supplier to calibrate and adjust all inspection, measuring, and test equipment including measurement devices at prescribed intervals, or prior to use, against certified equipment having a known valid relationship to nationally recognized standards. 

Measurements were made using two types of passive track-etch alpha dosimeters. One of them was the bare detector of CR-39. After exposure these dosimeters were etched by 30 % NaOH at 70°C for 5 hours. The number of pits was scored under a microscope with a television camera in Shiga University of Medical Science. Methods of calibration and adjustment for deposition of radon daughters introduced by Yonehara (Yonehara et al., 1986) were adopted. The second detectors were Terradex type SF (Alter and Price, 1972). These detectors consist of a plastic cup, covered by a filter to allow entry only of gases, with a track-etch detector inside. The reading of results was carried out by Terradex Corp. in Walnut Creek, California, U.S.A.. The measurements of radon concentration were carried out by both methods in each location, except for Hokkaido where the measurements were done only by Terradex. However, the data obtained by CR-39 detectors will be mainly presented in this paper, because the two methods did not give identical results as separately reported in this proceedings by Yonehara et al. (Yonehara et al., 1986). 

All inspection, measuring, and test equipment is capable of the accuracy and precision necessary. Prior to use, all inspection, measuring, and test equipment is identified, calibrated, and adjusted as required. Calibration and adjustments are made are against standards of certified equipment, traceable to the National Institute of Standards and Technology (NIST, where no such standard exists, the basis used for calibration is documented). Inspection, measuring, and test equipment is identified with a suitable indicator or approved identification record to show the calibration status. 

In the present work, we evaluate the high-spin/low-spin energy separations for various Co-N bond lengths, using initio molecular orbital theory (RHF and UHF), including electron correlation via perturbation theory. The known energy separation for the 3+ complex at its equilibrium geometry is used to calibrate and adjust the raw calculated results. 

A dilatometer constructed by Sauer is shown in Fig. 45. The sensing element is a linear variable differential transformer, whose rectified output is recorded directly. A pivot arm connects the transformer (A) to the bearing arm (B) and a micrometer screw allows for calibration and adjustment of the transformer. By adjustment of the compensating screw, the pivot arm can be moved so that the contact point (B) is exactly one sample length from the fulcrum. Temperatures above and below ambient can be obtained by circulating gas round the specimen. 

Panel Q also carries a number of..knobs fof adjustment of zero, calibration, and adjustment of.balance voltage for the galvanometers There are, moreover, two additional items which deserve -particular mention. One is the set of three (out, stop, and in) push button controls in the lower left corner for movement of the fission chamber. < The other, is the pair of alarm lights and reset buttons at the upper r.ight -hand corner-which work from phototube alarm circuits when any of the galvanometers go off scale. 

TLS provides abundant spatial information, the subsequent treatment of which allows georefer-encing of the captured point clouds, its representation in 3D digital format, digital elevation models, point cloud videos, orthoimages, etc. Since the different equipment models stand as black boxes [8], and in order to make sure that the results are satisfactory, the uncertainty sources coming up during the measurement process must be detected, each contribution should be quantified and the appropriate calibration and adjustment processes should be developed. 

IV.60. Documented measures should ensure that tools, gauges, instruments, test software and other inspection, measuring and test equipment, and other devices used in determining conformity to acceptance criteria, are of the proper range, type, accuracy and precision. They should be properly handled and stored, controlled, calibrated and adjusted at specified intervals to maintain accuracy. Records of calibration should be maintained and be adequate for traceability of measurement, to national or international standards, when necessary. When deviations beyond prescribed limits are detected, an evaluation should be made of the validity of previous measurements and tests, and acceptance of tested items reassessed. 

Setting up, calibrating and adjusting a personal sampling pump... 

Check all controllers for correct calibration and adjust as necessary Calibrate all transmitters and set gauges as required Check all PE switches... 

In order to calibrate and adjust the scale standards are used, which associate a precisely defined output measurement value to a measured quantity. 

Special features Fully automatic calibration and adjustment... 

I. C systems for process plants depend for their safe and continuous operation, under normal and abnormal conditions, on independent dedicated electrical, pneumatic and possibly hydraulic sources of power. These power sources should be installed, inspected, tested and made operational as early as practicable, so as to be available for the inspection, testing, calibration and adjustment of the components and ensembles constituting the plant s I. C systems. Batteries provide DC power directly or provide secure AC power through an inverter. Instrument air is produced by oil free compressor sets delivering to an air receiver via filters and air dryers. In an application where hydraulic power is required, the necessary pump sets, filters, reservoir and accumulator, can be integrated into a self-contained power pack. 

When the system has been calibrated and adjusted to the light settings in the environment it is very robust and is able to track multiple users accurately. Tests have shown that up to fifteen users, i.e. at least 30 limb contact points can be tracked simultaneously on the floor though space is limited. 

Check the calibration and adjust if needed by performing the routine calibration check described in 10.3. 

The systematic deviation between the true sample temperature and the measured temperature, which is heating rate dependent, can be determined and corrected through temperature calibration and adjustment. This is usually done using pure metals that have good thermal conductivity properties. Real samples (e.g. polymers) can of course exhibit quite different thermal conductivity behaviour. For this reason, the measured sample temperature will still be expected to show a slight dependence on the heating rate, even if the instrument has been properly adjusted. The effect is very small with the onset temperature, but is more pronoimced with the peak temperature. 

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