Curves for evaluation

Kulikov, A. V. and Likhtenstein, G. I. (1974) Application of saturation curves for evaluating distances in biological objects by the method of double spin-labels. Biofizika. 19,420-424. 

Figure 16-3. Bergum acceptance curve for evaluating content uniformity (CU) data. Note The curve shows that for a relative standard deviation (%RSD) of 4.5%, a sample mean value (SMV) of 100% must be achieved for the manufacturing process to be judged as validated.

Paxton, S. T., Szabo, J. O., Ajdukiewicz, J. M. Klimentidis, R. E. 2002. Construction of an intergranular volume compaction curve for evaluating and predicting compaction and porosity loss in rigid-grain sandstone reservoirs. American ciation of Petroleum Geologists Bulletin, 86, 2047-2067. 

You have to determine (a) formaldehyde and acetaldehyde in 50 samples of white wine per day (b) 2,4,6-trinitrotoluene in white powder samples which might be potential material in making bombs—3 to 5 samples per month (c) copper content in a rare Etruscan vase (d) a toxic keto compound in an antibiotic, the analysis being done in a production-line quality-control laboratory in a pharmaceutical company. In which cases and why would you use a standard-addition method and when would you use a calibration curve for evaluating current-versus-voltage curves ... 

Absorption at 560 nm is used to determine the amount of the amino acid eluted from the column. Proline, a secondary amine, gives a yellow colored compound and this necessitates a second monitoring wavelength (440 nm). Continuous recording of absorption results in an elution diagram which is then compared with a standard curve for evaluation. Contemporary instruments provide a printout of the computed results of the analysis. 

There is a close relation between this function and the area under the standard normal curve. For evaluation it is convenient to use z instead of x then erf z may be evaluated from the area F (z) by use of the relation... 

The predicted cumulative cash-flow curve for a project throughout its life forms the basis for more detailed evaluation. Many quantitative measures or indices have been proposed. In each case, important features of the cumulative cash-flow curve are identified and transformed into a single numerical measure as an index. 

Sketching an Acid—Base Titration Curve To evaluate the relationship between an equivalence point and an end point, we only need to construct a reasonable approximation to the titration curve. In this section we demonstrate a simple method for sketching any acid-base titration curve. Our goal is to sketch the titration curve quickly, using as few calculations as possible. 

The superpositioning of experimental and theoretical curves to evaluate a characteristic time is reminiscent of the time-tefnperature superpositioning described in Sec. 4.10. This parallel is even more apparent if the theoretical curve is drawn on a logarithmic scale, in which case the distance by which the curve has to be shifted measures log r. Note that the limiting values of the ordinate in Fig. 6.6 correspond to the limits described in Eqs. (6.46) and (6.47). Because this method effectively averages over both the buildup and the decay phases of radical concentration, it affords an experimentally less demanding method for the determination of r than alternative methods which utilize either the buildup or the decay portions of the non-stationary-state free-radical concentration. 

Figure 9.14 Calibration curve for GPC as log M versus the retention volume Vj, showing how the location of the detector signal can be used to evaluate M. Also shown are the void volume Vy and the internal volume Vj in relation to Vj, and KVj as a fraction of Vj.

Inorganic heavy metals are usually removed from aqueous waste streams by chemical precipitation in various forms (carbonates, hydroxides, sulfide) at different pH values. The solubiUty curves for various metal hydroxides, when they are present alone, are shown in Figure 7. The presence of other metals and complexing agents (ammonia, citric acid, EDTA, etc) strongly affects these solubiUty curves and requires careful evaluation to determine the residual concentration values after treatment (see Table 9) (38,39). 

Figure 2-43. Evaluation curves for friction losses of air and steam flowing turbulently in commercial pipe at low pressures. By permission, Standards for Steam Jet Ejectors, 4th Ed., Heat Exchange Institute, 1988.

Figures 12-65 and 12-65A give the relationship between polytropic and adiabatic efficiencies. The adiabatic efficiency can be calculated from operating data, and the polytropic efficiency can be read from the curves. For other cases, ep may be calculated from the preceding relation and the adiabatic efficiency may be determined from the curves. Figure 12-66 illustrates the relationships that may exist while evaluating a particular compressor design.

In the case of the ASME codes for nuclear pressurised components, the questions of fatigue design and of flaw evaluation are dealt with separately in ASME Section III and Section XI Appendix A, respectively. The design S-A curve for machined butt welds typical of thick section pressurised components is set at a factor of two on stress range or twenty on cyclic life, whichever is more conservative, below the mean of S-N data developed on smooth cylindrical specimens in air. (A somewhat similar design curve obtained by a different method from experimental S-A data for machined butt welds is given in British Standard 5500.) These safety factors are intended to encompass any adverse influence of minor weld defects, size effects, data scatter and environment. As far as environmental effects are... 

It is evident from previous considerations (see Section 1.4) that the corrosion potential provides no information on the corrosion rate, and it is also evident that in the case of a corroding metal in which the anodic and cathodic sites are inseparable (c.f. bimetallic corrosion) it is not possible to determine by means of an ammeter. The conventional method of determining corrosion rates by mass-loss determinations is tedious and over the years attention has been directed to the possibility of using instantaneous electrochemical methods. Thus based on the Pearson derivation Schwerdtfeger, era/. have examined the logarithmic polarisation curves for potential breaks that can be used to evaluate the corrosion rate however, the method has not found general acceptance. 

Prepare a calibration curve for each element (see Section 21.16) and use this to evaluate the concentration of any unknown sample (see Note). 

It now remains to evaluate the integral JdHo/(H f — Ho) between the limits, Hai =27.7 kJ/kg and Ho2 = 76.5 kJ/kg. Various values of Ha between these limits are selected and the value of 9 obtained from the operating line. At this value of 9, now Of, the corresponding value of H f is obtained from the curve for... 

It is impossible to carry out this program of directly evaluating the energy integral except in the simplest cases but rough energy curves for various electronic structures can often be constructed by semi-empirical methods, and the discussion outlined above carried out with them. Thus information regarding the repulsive forces between ions obtained from the observed properties of ionic crystals can be used for ionic states of mole-... 

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