Vs. time

Off-line analysis of stored data review of the stored data, organize data in different presentation windows, plot AE and plant parameters data so as to enable comparison and coirelation with the possibility to present data (histogram of AE events vs position, plant parameters and/or AE parameters vs time) conditioned in terms of time interval (initial time, final time) and/or position interval (defined portion of the component = initial coordinate, final coordinate) and/or plant parameters intervals (one or more plant parameters = initial value, final value). 

Fig.6 Example of trend vs time parameter representation the view is Epical of a paper recorder, with time in Y coordinate decreasing from the top to the bottom. The eight top buttons represent the different choice of plant parameters...

Finally, preliminary diagnostic evaluation criteria, based on preventive identification of critical areas of interest on the monitored item, spatial concentration of localized AE events as compared with average AE event density and evolution of local event concentration vs time and/or plant parameters, have been worked out and submitted to extensive testing under real operation conditions. Work on this very critical issue is still to be consohdated. 

Different plant operating conditions (steady load, load variations, startups / shutdowns) have been encountered during the monitoring period. Electrical load, steam pressure and steam temperature values vs time have been acquired and stored during the entire period. At the same time, the RMS values of the acoustical background noise were have been continuously checked and stored, thus providing a quick check of proper instrumentation condition and a correlation between variations of plant parameters and the acoustical behaviour of the components. 

The same general comments hold as for Unit 3. Figure 7 provides an example of the AE monitoring data collected from 19.06.97 to 16.07.97, in terms of the main plant parameters vs time (fig. 7a), as well as of the AE RMS values (fig. 7b). 

Fii .5 600 MW ENEL power plant, unit 3. Monitoring period from 22-01-1997 to 03-03-1997. i ig..3 i Mam plant parameteis and aiimilalivc AR events vs lime Fig.5b AE RMS valties vs time... 

A graph or chart of ion current (y-axis) vs. time (x-axis) is therefore a succession of peaks corresponding to components eluting from the chromatographic column. This chart is called a total km current (TIC) chromatogram. 

The definition of polymer thermal stabiUty is not simple owing to the number of measurement techniques, desired properties, and factors that affect each (time, heating rate, atmosphere, etc). The easiest evaluation of thermal stabiUty is by the temperature at which a certain weight loss occurs as observed by thermogravimetric analysis (tga). Early work assigned a 7% loss as the point of stabiUty more recentiy a 10% value or the extrapolated break in the tga curve has been used. A more reaUstic view is to compare weight loss vs time at constant temperature, and better yet is to evaluate property retention time at temperature one set of criteria has been 177°C for 30,000 h, or 240°C for 1000 h, or 538°C for 1 h, or 816°C for 5 min (1). 

Statistical quaUty control charts of variables are plots of measurement data, preferably the average result of repHcate analyses, vs time (Fig. 2). Time is often represented by the sequence of batches or analyses. The average of all the data points and the upper and lower control limits are drawn on the chart. The control limits are closely approximated by the sum of the grand average plus for the upper control limit, or minus for the lower control limit, three times the standard deviation. 

The check sheet shown below, which is tool number five, is a simple technique for recording data (47). A check sheet can present the data as a histogram when results are tabulated as a frequency distribution, or a mn chart when the data are plotted vs time. The advantage of this approach to data collection is the abiUty to rapidly accumulate and analy2e data for trends. A check sheet for causes of off-standard polymer production might be as follows ... 

Fig. 17. Viscoelastic material stress ( and strain (---------) ampHtudes vs time where 5 is the phase angle that defines the lag of the strain behind the...

The advantages claimed for organotin polymer-based antifouling paints include constant toxicant deHvery vs time, erosion rate and toxicant deHvery are controUable, no depleted paint residue to remove and dispose, 100% utilization of toxicant, polishing at high erosion rates, surface is self-cleaning, and function is continuously reactivated. 

Fig. 6. Bayard-Alpert gauge response vs time upon cutting off power to Orbitron pump (27). To convert Pa to torr, divide by 133.3.

Further hydrolysis of the carbon disulfide and the trithiocarbonate produces hydrogen sulfide, etc (33). In another study of the decomposition of sodium ethyl xanthate [140-90-9] in flotation solutions, eleven components of breakdown were studied. The dependence of concentration of those components vs time was examined by solving a set of differential equations (34). 

End Point vs Kinetic Methods. Samples may be assayed for enzymes, ie, biocatalysts, and for other substances, all of which are referred to as substrates. The assay reactions for substrates and enzymes differ in that substrates themselves are converted into some detectable product, whereas enzymes are detected indirectly through their conversion of a starting reagent A into a product B. The corresponding reaction curves, or plots of detector response vs time, differ for these two reaction systems, as shown in Eigure 2. Eigure 2a illustrates a typical substrate reaction curve Eigure 2b shows a typical enzyme reaction curve (see Enzyme applications). 

Fig. 5. Tensile elongation vs time demonstrating creep behavior of ceramics. Section I is primary creep II, secondary or steady-state creep III, tertiary...

The performance of the dmg dehvery system needs to be characterized. The rate of dmg release and the total amount of dmg loaded into a dmg dehvery system can be deterrnined in a dissolution apparatus or in a diffusion ceU. Typically, the dmg is released from the dmg dehvery system into a large volume of solvent, such as water or a buffer solution, that is maintained at constant temperature. The receiver solution is weU stirred to provide sink conditions. Samples from the dissolution bath are assayed periodically. The cumulative amount released is then plotted vs time. The release rate is the slope of this curve. The total dmg released is the value of the cumulative amount released that no longer changes with time. 

Compression Set Resistant. One property of fluorocarbon elastomers that makes them uniquely valuable to the sealing industry is their extreme resistance to compression set. Figure 4 plots compression set vs time for compounds prepared especially for compression set resistance (O-ring grades). 

Coulometry. If it can be assumed that kinetic nuances in the solution are unimportant and that destmction of the sample is not a problem, then the simplest action may be to apply a potential to a working electrode having a surface area of several cm and wait until the current decays to zero. The potential should be sufficiently removed from the EP of the analyte, ie, about 200 mV, that the electrolysis of an interferent is avoided. The integral under the current vs time curve is a charge equal to nFCl, where n is the number of electrons needed to electrolyze the molecule, C is the concentration of the analyte, 1 is the volume of the solution, and F is the Faraday constant. 

Like frequency estimates, consequence estimates can have very large uncertainties. Estimates that vary by orders of magnitude can result from (1) basic uncertainties in chemical/physical properties, (2) differences in average vs. time-dependent meteorological conditions, and/or (3) uncertainties in the release, dispersion, and effects models. Some... 

Fig. 17-1 Protection current vs. time for uncoated steel in a calm sea.

Figure 19.6. Acelal copolymer static fatigue failure vs time at 20°C (R.H. ca 65%) (ICI Publicity...

PlotLabel - FontForm["Level vs Time", "Times-Roman" A4 ]] ... 

FIG. 18 Mean-square displacements gi t) vs time for chains with 7 = 128 in a narrow non-adsorbing sUt (Z)= l,e = 0) at density cp = 1.5. Straight lines show effective exponents = 0.56, and = 0.84, respectively. Broken horizontal lines show (above) and (below), (b) Log-log plot of the relaxation time r 3 vs N for the case (D = 1, e = 0) and various densities (p as indicated. Straight lines show interpretations in terms of effective exponents Zgff (r oc [16]. 

Obviously a plot of In (< — Cz) vs. time will be nonlinear (except for the special case ki = k-i). However, suppose ki k2, then at some time essentially all of reactant A will have reacted, and Eq. (3-16) becomes... 

In this system the product of the first reaction possesses an absorption maximum at 222 nm and the final product has k ax = 288 nm. The initial reactant is essentially nonabsorbing at these wavelengths. Hence, spectrophotometric observation at 222 and 288 nm allowed two simultaneous equations to be written, and thus Cb and Cc were determined as functions of time. From the known quantity c°, the concentration Ca was calculated with Eq. (3-28). The rate constant A , was then found from the plot of In Ca vs. time. An estimate of rate constant k was obtained from a plot of In Cb vs. time in the late stages of the reaction, and this value was refined by curvefitting the Cb and Cc data. Figure 3-6 shows the data and final curve fits. 

Thus, the technique consists of a transformation from the time differential dt to the area differential dQ, and the essential effect of this transformation is a reduction by one of the apparent order of the reaction. The variable 6 is the area under the curve of Cb vs. time from t = 0 to time t. With modem computer techniques for integrating experimental curves, this method should be attractive. 

A typical plot of total energy and temperature vs time (for aspirin, with the temperature constrained to be constant) is shown in Figure 2.1. 

The kinetics of the reactive compatibilization of nylon-6-PP by acrylic acid modified PP was investigated by Dagli et al. [47]. The compatibilization reaction in this system involved the reaction between the acid group of acrylic acid modified PP and the amine group of nylon-6. A typical intensive batch mixer torque (t) vs time (t) trace for a ternary blend showing an increase in mixing torque upon the addition of PP-g-AA to a binary PP-NBR (85 7.5) blend is shown in Fig. 3. The kinetic... 

Figure 3 Torque vs time trace for the PP-N6-PP-g-AA ternary blend. Source Ref. 47.

Figure 4>352b. Driller s method—Schematic diagram of casing pressure vs. time, t = kick fiuid out the top of the hole t = kick fluid out of the hole t = kill mud at the bottom of the hole t = killing procedure completed.

Fig. 19.1 Rate vs. time curve showing diminishing rate of attack (after Proc. xl.S. T.M., SI,...

Legault, Mori and Leckie have used open-circuit potential vs. time measurements and cathodic reduction of rust patinas for the rapid laboratory evaluation of the performance of low-alloy weathering steels. The steel specimens are first exposed for 48 h to the vapour of an 0-(X)l mol dm sodium bisulphite solution maintained at 54°C (humid SOj-containing atmosphere) to stimulate corrosion under atmospheric conditions. They are then subjected to two types of test (tt) open-circuit potential-time tests for periods up to 3 000 s in either distilled water or 0 -1 mol dm Na2S04 and... 

A relationship was also established between the oxide-reduction time and time of exposure, and the results for a mild steel and a lCu-3Ni weathering steel were similar to those obtained by mass loss. The authors give various expressions that relate oxide-reduction time (min) with corrosion rate (mm/y), and claim that a short exposure to a laboratory SO2 atmosphere followed by determining the E vs. time and oxide-reduction time provides a rapid method of evaluating weathering steels. 

The decomposition of A2B2 to A2 and B2 at 38CC was monitored as a function of time. A plot of 1/[A2B2] vs. time is linear, with slope 0.137/M-min. 

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