Attenuation Data

Attenuation Data system Vertical scale Changes appearance of chromatogram (makes peaks shorter or taller) Does not change peak recognition, retention time, area or width Does not affect the raw data... 

Once the experimental errors are attenuated, data are prepared for the calculation of kinetic variables. Frequently, it is necessary to determine the rates (Equations 4 to 8), and the possible approaches are ... 

Consequently, the slope of the low q echo attenuation data allows (Z (A))/. to be measured directly. This represents the simplest of all possible signal analysis in the case of the narrow gradient pulse PGSE experiment. In the study of hindered and restricted diffusion, such an analysis provides a useful guide to interdependence of length and time... 

Diamond et al. [127] have estimated UVR doses in wetlands using this approach. Typical UVR doses were estimated by first generating maximal solar radiation doses for each day using a radiative transfer model, SBDART [113]. The model produced values for the full spectrum of solar radiation, from 280 to 700 nm, for cloudless conditions. These maximal values were then modified based on cloud cover effect estimates from 30 yr of historical solar radiation data (National Renewable Energy Laboratory, Department of Energy http //rredc.nrel.gov/solar/). The values derived in this procedure were estimated daily terrestrial, spectral (2 nm increments from 280 to 700 nm) solar radiation doses. Water column doses were then derived from absorption coefficients and spectral attenuation data described by Peterson et al. [128]. Although the focus of this effort was to characterize risk of UV-B radiation effects in amphibians, the procedure is directly applicable to phototoxicity, and the resulting UV-A radiation and spectral doses could be directly incorporated into calculation of possible effects. 

A least-squares linear fit was applied to the attenuation data of Fig. 5-3. An empirical equation,... 

We have analyzed the thermodynamic, magnetic and ultrasound attenuation data on oriented saaiples of the hlgh-T superconductors within the context of anisotropic Glnzburg-LSndau theory for coupled, even-parity superconducting states. We are able to present a consistent Interpretation of the data In terms of the coexistence of a quasi-two-dimensional d-wave state, with critical temperature T. - T and a more Isotropic mixed (s+d)-wave state with critical tempertaure T < T We predict the possibility of a "kink" in the temperature dependence of the lower critical field near 0 9T, which should be tested by experiments on single crystals. 

Brillinger, D. R. and Preisler, H. K. Further analysis of the Joyner-Boo-e attenuation data. Bulletin of the Seismological Society of America 75(2) (1985), 611-614. 

While the operating principles are relatively simple, the analysis of the attenuation data to obtain particle size distributions does involve a degree of complexity in fitting experimental results to theoretical models based on various acoustic loss mechanisms. The advent of high-speed computers and the refinement of these theoretical models has made the inherent complexity of this analysis of little consequence. In comparison, many other particle sizing techniques such as photoncorrelation spectroscopy also rely on similar levels of complexity in analyzing experimental results. 

Each model was applied to sugar attenuation data taken from multiple brewing fermentations (assessed using high-pressure liquid chromatography). Three techniques Akaike s (corrected) Information Criterion, comparison of the coefficients of determination (r ) and absolute residual sum of squares (RSS) were used to compare the fit of each model. Ideally, the data would adhere to a simplistic, theoretically derived formula such as a low parameter symmetric model. Unfortunately, the variability in both shape and lag time for each individual sugar necessitated a more flexible... 

Figure 3.4 Modelled maltose attenuation data (MG, modified Gompertz IBF, incomplete 3-function 5P, five-parameter logistic). The residuals for each model are depicted on the right.

Some large rooms convert to several smaller rooms with folding partitions. Some partitions are plastic. By itself, the plastic partitions do little to stop sound transmission. Most manufacturers incorporate lead strips into the sections that fold. The goal is to add mass to the partitions to reduce the amplitude of panel vibration and reduce sound transmission. Companies selling partitioning panels provide sound attenuation data for their products. 

In addition to the LIF-attenuation data for the Ca reagent atom in its various excitation levels, data for the yield of the reactive channel into electronically... 

When the dependent variable, P, is plotted on a linear scale, the power is ever increasing with time and the slope is variable. If the vertical axis is made logarithmic, the plot becomes linear because an exponential function, when plotted on a logarithmic scale, is a straight line. This phenomenon is sometimes useful in plotting radioactive decay and shielding attenuation data. 

Figure 4.12 Squares PMMA internal friction as a function of temperature at a frequency of 535 Hz. Full circles indicate the attenuation data taken from the ultrasonic measurements at 15 MHz from Ref. [24]. Solid and dotted lines the calculated values for v = 535 Hz and v = 15 MHz following the modified tunneling model considering a thermally activated relaxation rate. For more details see text.

Although there is a difference between the exponent in Eq. 11 used to fit the spin-echo attenuation data and the exponent obtained from plots of vs. for consistency we used the same symbol a regardless of the... 

Fig. 6 shows attenuation data obtained at room temperature for... 

Figure 2.2 Attenuation data, /(/)//(0), on a logarithmic scale, vs. pressure, for the scattering ofathermal 1100 K) beam ofCsCI byAr atoms and by the polar CH2F2 molecules in a 44 mm cell. The log of the transmission is observed to decrease linearly with the pressure of the target gas [adapted from H. Schumacher, R. B. Bernstein, and E. W. Rothe, J. Chem. Phys. 33, 584 (I960)].

Experimental data show a tendency for some correlations and remarkable differences between velocity and attenuation properties. In a fundamental paper, Winkler and Nur (1982) discuss the relations between these two ratios Fig. 6.64 shows a separation between dry, partly, and fully saturated Massillon sandstone in a Qp/Qs versus plot. Winkler and Nur (1982) note that 2p/2s is much more sensitive to degree of saturation than is V V The data for dry and partially saturated rock in particular are not significantly separated by Fp/Fs, but 2p/2s shows a distinct difference. On the other hand, Fp/Fs clearly indicates fuUy saturated rocks. Winkler and Nur (1982) therefore conclude that by combining both velocity and attenuation data, it may be possible to obtain a more precise estimate of degree of saturation than with Fp/F alone". 

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