Dynamic range definition

Figure 7.6. (a) Definitions of success rate and relative dynamic range, (b) Model of a proteomics experiment. (See color insert.)... 

Only through discrete particle counting can air cleanliness be verified, and the cleanliness class of the sampled environment established. " Periodic in-process monitoring of workstations, buffer rooms, anterooms, production areas, and any other area about which a definitive air cleanliness statement is made or reasonably assumed, should be carried out in accordance with SOPs or industry standards. A discrete particle counter (DPC) with an adequate sampling rate, calibration features, and dynamic range should be used for sample acquisition, based on the specified air cleanliness level. ... 

SIT. ISIT. Under the definition of dynamic range as the ratio of the largest readable signal to the rms noise of the detection system, there are actually at least four kinds of dynamic range values. We will confine our discussion to the following three types of dynamic range. 

Linearity And Dynamic Range. There is extensive evidence that emission intensities of many atomic lines excited in an ICP source are linearly related to concentration of the corresponding analytes over a range of at least one million. Trace and major constituents are therefore determinable without changes in the operating condition of the plasma. Ideally, the detection system should have a comparable linear dynamic range performance. As previously discussed (45), there are several definitions of dynamic range that are applicable to the SPD detection system. 

A first alternative to this method is that of the linear dynamic range, in which the ratio between the concentration giving a 10% deviation and the concentration equivalent to the baseline noise is given. In the second alternative the criterion for linearity is taken not as 10%, but as three times the standard deviation of measurements inside this range. For the present purpose, these methods have the practical drawback that the uncertainty in the definition of noise enters that of the linear range as well. 

Values of r can vary between -1 and 1, with 1 indicating a perfect linear correlation, -1 being a perfect inverse linear correlation, and 0 indicating an absence of correlation. The definition of what constitutes a good value for r is somewhat subjective and situation dependent, and could easily fill an entire chapter or even a book. As we will see in subsequent sections, the dynamic range of the data being considered can have a dramatic effect on Pearson s r. We will also see that when comparing values of Pearson s r for dilferent models, we must consider the confidence intervals around r. 

Fig. 7.6. Illustration of the definition of dynamic range for a TCD. Copyright ASTM. Reprinted with permission. From Miller, J. M., Chromatography Concepts and Contrasts, John Wiley Sons, Inc., New York, 1987, p. 96. Reproduced courtesy of John Wiley Sons, Inc.

Figure 1-13 illustrates the definition of the dynamic range of an analytical method, which extends from the lowest concentration at which quantitative measurements can be made (limit of quantitation, or LOO) to the concentration at which the calibration curve departs from linearity by a specified amount (limit of linearity, or LOL). Usually, a deviation of SSI. from linearity is considered the upper limit. Deviations from linearity are common at high concentrations because of nonideal detector responses or chemical effects. The lower limit of quantitative measurements is generally taken to be equal to ton times the standard deviation of repetitive measurements on a blank, or 10j . At this point, the relative standard deviation is about 3(1% and decreases rapidly as concentrations become larger. 

Relaxation measurements provide another way to study dynamical processes over a large dynamic range in both thermotropic and lyotropic liquid crystals (see Sec. 2.6 of Chap. Ill of Vol. 2A). The two basic relaxation times of a spin system are the spin-lattice or longitudinal relaxation time 7] and the spin-spin or transverse relaxation time T2. A detailed description, however, requires a more precise definition of the relaxation times. For spin 7=1, for instance, two types of spin-lattice relaxation must be distinguished, related to the relaxation of Zeeman and quadrupolar order with rates 7j"2 and Jfg. The relaxation rates depend on spectral density functions which describe the spectrum of fluctuating fields due to molecular motions. A detailed discussion of spin relaxation is beyond the scope of this... 

A definite advantage of using a THz-TDS instrument is that its dynamic range is much greater than that of an FT-IR spectrometer, so that it is advisable to use THz-TDS for purposes that can make the most of this advantage. 

Write out detailed definitions, with illustrations if appropriate, for the following terms Chronovoltabsorptometry oxidative and reductive Switching Times Electrochromic, Electrochemical and Charge Cyclabilities Charge Capacity Dynamic Range Open Circuit Memory Bandgap Solar Absorptance Thermal Emittance. 

All the electrochromic performance parameters cited earlier in Chapter 3 are valid equally for electrochromic devices as for laboratory-cell electrochromic systems Dynamic range switching time cyclability open circuit memory. The reader is referred to this chapter for further reference and definitions. 

Akhtar et al. [902(a)] were one of the first to describe completely assembled, sealed, solid-state electrochromic devices based on CPs. In one set of devices, the fairly common Li-triflate/Poly(ethylene oxide) (PEO)/acetonitrile formulation for nonaqueous solid electrolytes was used. However, in another set, the unique combination of poly(ethyleneimines) of different MWt and protonic acids such as hydrochloric, sulfuric, phosphoric, acetic and poly(styrene sulfonic) was used. Additionally, the films of the CP, P(ANi), were prepared electrochemically as well as by sublimation, and in one set of devices Fe-tungstate was used as a counter electrode to provide a definitive counter electrode reaction (Lithiation). While cyclabilities to several thousand cycles were claimed, the electrochromic dynamic range and other parameters were fairly poor, as seen in Figs. 20-3. Very rapid switching times have been claimed for many P(ANi)- or P(ANi)-derivative based devices. For example. Ram et al. [902(b)] claimed a 143 ms switching time for liquid-electrolyte devices based on poly(aniline-co-o-anisidine). 

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