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Analysis of the Measurements

Bayesian Methods for Structural Dynamics and Civil Engineering [Pg.68]


There are two main types of viscometer rotary instruments and tubular, often capillary, viscometers. When dealing with non-Newtonian fluids, it is desirable to use a viscometer that subjects the whole of the sample to the same shear rate and two such devices, the cone and plate viscometer and the narrow gap coaxial cylinders viscometer, will be considered first. With other instruments, which impose a non-uniform shear rate, the proper analysis of the measurements is more complicated. [Pg.96]

Kemblowski, M. W. andChiang, C. Y., 1988, Analysis of the Measured Free Product Thickness in Dynamic Aquifers In Proceedings of the National Water Well Association of Ground Water Scientists and Engineers and the American Petroleum Institute Conference on Petroleum Hydrocarbons and Organic Chemicals in Ground Water Prevention, Detection and Restoration, Vol. I, November, 1988, pp. 183-205. [Pg.205]

In this case, although the reported enthalpy of reaction refers to the difference 7/yh (B) —//ja (A), where Ta and 7], represent the selected temperatures of the peak onset and offset, respectively, an approach based on the thermokinetic analysis of the measured curve was used to compute the peak baseline, and a very detailed description of the method used to derive the thermodynamic and kinetic data is given by the authors. Finally, a general and very important application of... [Pg.186]

The improvement of the management of processes comes from the measurements of the performance and effectiveness of processes and the analysis of the measurement results. This is the... [Pg.65]

A detailed analysis of the measurements, Fig. 3.33, suggests that the binary rotovibrational spectra are somewhat more complex than the simple discussion above may have suggested. Figure 3.33 shows a measurement like the ones of Fig. 3.31, but at an even lower temperature so that a overlapping of the various lines is minimal. Low temperature favors the detailed analysis of the spectral profiles. [Pg.111]

The experiment depicted in Fig. 2 was designed to test the validity of the two fundamental assumptions introduced above, that is, linearity and reciprocity. Isolated mitochondria from rat liver were incubated in the presence of a constant input force A o.1 The output force Xp was varied within the physiologically relevant range through additions of glucose plus hexokinase. A linear regression analysis of the measured flows Jp and J0 as a function of Xp showed that linearity as well as reciprocity were fulfilled within experimental error. [Pg.142]

Fig. 36. Differential and integral rate distributions as obtained from a CONTIN analysis of the measurements in Fig. 35. The central peak is enhanced in the filtered stochastic TDFRS experiment... Fig. 36. Differential and integral rate distributions as obtained from a CONTIN analysis of the measurements in Fig. 35. The central peak is enhanced in the filtered stochastic TDFRS experiment...
Method validation is important to ensure that the analytical method is in statistical control. A method may be validated by the so-called method evaluation function (MEF) (Christensen et al., 1993), which is obtained by linear regression analysis of the measured concentrations versus the true concentrations. A true concentration in a solution can be obtained by use of a high purity standard obtained from another manufacturer or batch than the one used for calibration. Both the high purity standard and the solvent are weighed using a traceable calibrated balance. If certified reference material is available this is preferred. The method evaluation includes the most important characteristics of the method as the following elements (see Figure 2.7) ... [Pg.37]

The results of regression analysis of the measured data indicate that the droplet size distributions both before and after the impingement can be expressed by the following equation ... [Pg.111]

A dynamic experimental method for the investigation of the behaviour of a nonisothermal-nonadiabatic fixed bed reactor is presented. The method is based on the analysis of the axial and radial temperature and concentration profiles measured under the influence of forced uncorrelated sinusoidal changes of the process variables. A two-dimensional reactor model is employed for the description of the reactor behaviour. The model parameters are estimated by statistical analysis of the measured profiles. The efficiency of the dynamic method is shown for the investigation of a pilot plant fixed bed reactor using the hydrogenation of toluene with a commercial nickel catalyst as a test reaction. [Pg.15]

A few developments have been published recently that attempt to incorporate such experimental inconsistencies into the numerical analysis of the measurements [33-35], The central formula, the set of differential equations that needs to be integrated, can be written in a very general way. [Pg.253]

The best-developed way to measure the association of ions is through the measurement of electrical conductance of dilute solutions. As mentioned, this realization occurred in the nineteenth century to Arrhenius and Ostwald. An elaborate development of conductance equations suitable to a range of ion concentrations of millimolar and lower by many authors (see Refs. 5, 33 and 34 for critical reviews) has made the determination of association constants common. Unfortunately, in dealing with solutions this dilute, the presence of impurities becomes very difficult to control and experimenters should exercise due caution, since this has been the source of many incorrect results. For example, 20 ppm water corresponds to 1 mM water in PC solution, so the effect of even small contaminants can be profound, especially if they upset the acid-base chemistry of association. The interpretation of these conductance measurements leads, by least squares analysis of the measurements, to a determination of the equivalent conductance at infinite dilution, Ao, the association constant for a positively and negatively charged ion pair, KA, and a distance of close approach, d, using a conductance equation of choice. One alternative is to choose the Bjerrum parameter for the distance, which is defined by... [Pg.86]

Moreover, TR-XAFS data reduction needs to be performed even at an early stage of a TR-XAFS experiment. To use the available beamtime as efficiently as possible, it is crucial to monitor the progress of a TR experiment by a continuous analysis of the measured spectra. (Compilations of XAFS software can be found at http //www.esrf.fr/computing/... [Pg.431]

Usually, the absorption coefficient of the conducting crystals is so high that producing a crystal sufficiently thin and suitable for absorption measurements presents a great difficulty. If this is so, the bulk optical constants of a solid may be computed from the normal-incidence reflectivity of that material over an extended range of frequencies, followed by a Kramers-Kronig analysis of the measurements [12,14]. In this method the real, n, and imaginary, k, parts of the complex index of refraction... [Pg.231]

Figure 9 Real part of the frequency-dependent conductivity of TEA(TCNQ)2 as deduced by dispersion analysis of the measured reflectivity at 300 K (a) and calculated theoretically according to the dimer model (b). (From Ref. 53.)... Figure 9 Real part of the frequency-dependent conductivity of TEA(TCNQ)2 as deduced by dispersion analysis of the measured reflectivity at 300 K (a) and calculated theoretically according to the dimer model (b). (From Ref. 53.)...
The expressions that can be used in the analysis of the measured autocorrelation response C(r) are given below for the case of heterodyne and homodyne detection. Homodyne detection applies to the case where the interface does not contribute to the scattering. Heterodyne detection applies to cases where the interface itself contributes significantly to the scattering (perhaps due to roughness). [Pg.190]

Single pulse experiments, as shown in Fig. 6.2-27, may be performed at different stages of conversion during a polymerization reaction. Analysis of the measured U versus t curves provides a very detailed picture of the polymerization kinetics, e.g., of rate coefficients as a function of monomer conversion (Buback, 1991). [Pg.542]

Makino et al. [63] measured the electrophoretic mobility of four types M1-M4 of hydrophilic gel microcapsules containing water prepared by an interfacial polymerization method. Each type of microcapsules has membranes of different compositions. The results of the analysis of the measured mobilitiy values on the basis of Eqs. (21.128) are given in Figs 21.10 and 21.11. [Pg.463]

The flow velocities in flame systems are such that transport processes (diffusion and thermal conduction) make appreciable contributions to the overall flows, and must be considered in the analysis of the measured profiles. Indeed, these processes are responsible for the propagation of the flame into the fresh gas supporting it, and the exponential growth zone of the shock tube experiments is replaced by an initial stage of the reaction where active centres are supplied by diffusion from more reacted mixture sightly further downstream. The measured profiles are related to the kinetic reaction rates by means of the continuity equations governing the one-dimensional flowing system. Let Wi represent the concentration (g. cm" ) of any quantity i at distance y and time t, and let F,- represent the overall flux of the quantity (g. cm". sec ). Then continuity considerations require that the sum of the first distance derivative of the flux term and the first time derivative of the concentration term be equal to the mass chemical rate of formation q,- of the quantity, i.e. [Pg.76]

This is confirmed by the experimental data and especially the extended analysis of the measured craze contours in high molecular weight PMMA. In this material an excellent fit is achieved by using a uniform craze stress in the Dugdale model... [Pg.148]

Hie main experimental techniques used to study oxygen migration in doped cerias are based on the AC impedance analysis of the measured electrical conductivity. It is found that the oxygen ion conductivity of ccria-bascd oxides depends strongly upon the dopant size and concentration. Both these factors are related to defect association between oxygen vacancies (the charge carriers) and other defects (mainly dopant substitutionals) which were discussed in section 8.3.2,. [Pg.282]

Furthermore, the values of the activation energies depend on the analysis method used. In addition, concentration of defects, homogeneity, and morphology of the sample, presence of catalyst particles, and other synthesis-related factors must be taken into consideration during the analysis of the measured data and interpretation of the results. Therefore, literature data on activation energies of carbon nanomaterials vary widely. [Pg.298]

In gases near the low-density limit, at all frequencies where significant CILS intensities are observed, the spectral intensity is proportional to the square of the density, g(co T)ccn, in harmony with the bimolecular origin (see, however. Ref 326). For an analysis of the measurements in terms of binary encounters, it is essential to demonstrate that the measured intensities are exactly proportional to the squared density at all frequencies. Linder such circumstances, the normalized spectra, g(tu T)ln, that is, the spectral shapes, do not depend on density. [Pg.450]

Table 2 Results of the estimation uncertainty for HPLC analysis of the measurement... Table 2 Results of the estimation uncertainty for HPLC analysis of the measurement...
The alkaline hydrolysis of phthalate diesters has been fit to the Taft-Pavelich equation (Eq. 9). Dimethyl phthalate (DMP) hydrolyzes to phthalic acid (PA) in two steps DMP + H20->MMP + CH30H and MMP + H20- PA + CH30H. The first step is about 12 times faster than the second, and nearly all the diester is converted to the monoester before product PA is formed. Other diesters are assumed to behave similarly. An LFER was obtained from rate measurements on five phthalate esters (Wolfe et al., 1980b). The reaction constants, p and S, were determined by multiple regression analysis of the measured rate constants and reported values of cr and Es for the alkyl substituents. The fitted intercept compares favorably with the measured rate constant (log kOH = — 1.16 0.02) for the dimethyl ester (for which a and s = 0 by definition). Calculated half-lives under pseudo-first-order conditions (pH 8.0, 30°C) range from about 4 months for DMP to over 100 years for di-2-ethylhexyl phthalate. [Pg.126]

In each case grinding for 20 min at room temperature yielded a product that had the same structure as that found in the host-guest compound grown as single crystals from solution. This was checked by analysis of the measured X-ray pow-... [Pg.428]


See other pages where Analysis of the Measurements is mentioned: [Pg.498]    [Pg.118]    [Pg.297]    [Pg.431]    [Pg.52]    [Pg.212]    [Pg.437]    [Pg.440]    [Pg.4]    [Pg.105]    [Pg.183]    [Pg.322]    [Pg.209]    [Pg.255]    [Pg.492]    [Pg.117]    [Pg.67]    [Pg.139]    [Pg.213]    [Pg.294]    [Pg.111]    [Pg.11]    [Pg.149]   


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