Chart speed

For the standby pump start test, which is an important test to ensure the pumps transfer without large pressure swings, a check should be made to see if the relief valves lift or the pressure falls to a pressure one half the difference between the standby pump start pressure and the compressor trip pressure. The transient pressure is best measured with a multipen chart recorder. The chart speed must be high enough to fully display the pressure variation. While not as good as the chart recorder, a simple shop-made test setup can be substituted. A spare switch is temporarily connected to the same location as the other switches. This switch is calibrated to close at the threshold acceptance pressure. The contacts are wired to a test light through a seal relay. The purpose of the relay is to maintain the cir-... 

It is seen from equation (7) that the diffusivity of a solute can be calculated from length and radius of the tube through which it passes, the flow rate, chart speed and the peak width at 0.6065 of the peak height. 

Columns - yBondagel 2000A, E-linear, 125 A Detection - RI 16X, SP4050 Attenuation 10 Chart speed - 4 cm/min Analysis time - 10 min Total plate count 10 plates... 

Attenuation Chart speed Injection volume Retention time for bispyribac-methyl... 

Having chosen the test mixture and mobile diase composition, the chromatogram is run, usually at a fairly fast chart speed to reduce errors associated with the measurement of peak widths, etc.. Figure 4.10. The parameters calculated from the chromatogram are the retention volume and capacity factor of each component, the plate count for the unretained peak and at least one of the retained peaks, the peak asymmetry factor for each component, and the separation factor for at least one pair of solutes. The pressure drop for the column at the optimum test flow rate should also be noted. This data is then used to determine two types of performance criteria. These are kinetic parameters, which indicate how well the column is physically packed, and thermodynamic parameters, which indicate whether the column packing material meets the manufacturer s specifications. Examples of such thermodynamic parameters are whether the percentage oi bonded... 

When the column is ready to be used, the chromatogram of a suitable test mixture should be obtained. The plate number and retention times of the test solutes should be noted, and the peaks should have a satisfactory shape (minimal tailing). For measurement of the plate number, the recorder should be used at a high chart speed. Fig. 5.1b(i) and (ii) show test chromatograms for a C-18 column prepared by the above method, and Fig. 5.1c and 5.Id show the data that you should report with the chromatogram. The retention for an unretained peak is taken as the small baseline disturbance just before the first peak. 

II See if you can complete the data in Fig. 5.Id from measurements on the chromatogram run at the higher chart speed. For reasons of space, the chart is marked at 10 cm past the injection point, so measure retention distances from the mark and add 10 cm. The correct values are given at the end of the Section. 

No. You do not need a stopwatch for the retention times. Find out the distance the chart paper crawls in, say, a minute. Then get out your little ruler and measure the distances from the starting point (either air peak or pen mark) to the midpoint of each peak on the baseline (Fig. 109). Dorl t be wise and do any funny angles. It won t help. You ve got the distances and the chart speed, so you ve got the retention time. It works out. Trust me. 

Chart speed or x-axis scale Data system Sets the x-axis scale for the plotted chromatogram Changes appearance of chromatogram Does not change peak recognition, retention time, area or width Does not affect the raw data... 

The output from the Grapple linear resistance bridge [7] was fed to a chart-recorder. For the experiments with styrene and indene, an instrument with a maximum speed of 20 cm-min 1 was used, but for the vinyl ethers a faster instrument with a maximum chart speed of 100 cm-min 1 was required. The signal from a WPA Scientific Instrument CMD 400 digital conductivity meter was fed to another recorder. At the end of each experiment, the electrical conductivity, Kf, of the reaction mixture was determined accurately with a Wayne-Kerr Autobalance bridge. 

If the same chart speed is selected for TGA, DTA, total and partial pressure curves, the curves can be interpreted simultaneously as a function of temperature by making a simple overlay. 

Variable chart speeds between the range of 5-50 mm. min-1 are most preferable in GC. 

CHART SPEED CHANGE (ii) ABSORPTION WITH REACTION... 

Chromatographic conditions Mobile phase H2O Flow 0.5 ml/min Chart Speed 1 in/min Volume injected 20yl Sample concentrations 1 mg/ml glucose and SX D2O Columns 25 cm x 4.1 mm 10 RI detector sensitivity X4. 

Fig. 7a and b. Gas chromatograms of PTH amino acids, a) Apolar amino acids b) silylated polar amino acids. 5 n Mol of each PTH-amino acid were applied. Chart speed 0.5 /min., gas chromatograph GC-45 , Beckman Instruments... 

SCAN SPEED 20°C/MIN RANGE 8 CAL/SEC CHART SPEED 40mm/MIN... 

Qualification report by Kaye validator with tunnel chart (speed and temperature)... 

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