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Applicators estimation

The most important uncertainty associated with the determination of is related to our ability to predict heats of formation of species. At present, AH( values for stable species can be predicted within 5kcal/mol using various forms of additivity principles, provided these rules are applicable. Estimations based on semiempirical quantum mechanics are more general and can be as accurate. Although ab initio calculations can be more accurate, they are computationally prohibitive. For radical species, the associated uncertainties in AHf generally are larger. [Pg.112]

Determine the size of the UASB reactor for the treatment of 1275 m /day of wastewater generated from a typical pharmaceutical plant with COD of 16,000 mg/L. The COD removal efficiency at an HRT of 4.7 days is 97%. If the following data and conditions are applicable, estimate (i) OLR and upflow velocity and (ii) methane yield and energy equivalent. [Pg.225]

As in Lyman s Handbook, emphasis is on broadly applicable estimation methods. Given the many and varied reasons that one might be interested in chemical property estimation, we believe that most users of this book will have less interest in chemical class-specific estimation methods. Obviously such methods are reliable only for that class, which may be defined very narrowly, and they may produce substantial yet unknown error if applied to compounds that differ significantly. Many of the newer methods were developed using much larger and more varied training sets, thus are more likely to be useful for diverse and/or structurally complex compounds. Therefore, in contrast to the situation that existed in 1982 when Lyman s Handbook was published, current users often do not need to make decisions about which of several class-specific methods seems most applicable to the compound of interest. [Pg.9]

Which model gives the best fit to the data If applicable, estimate the values of rA and... [Pg.165]

Other anode systems specially developed are sprayable conductive polymer coatings, metallized zinc coatings, and conductive paints. Typical primary anode for the conductive polymer or paints is platinized niobium wire attached to the concrete prior to application. Estimated cost is 76/m with a service life of five years. [Pg.233]

Assuming that the Arrhenius law is applicable, estimate the values of activation energy E and frequency factor kg. [Pg.111]

RE application Estimated RE stocks in 2020 (tons) Estimated average lifetime (years) Estimated RE old scrap in 2020 (tons)... [Pg.10]

Application Estimation of Prediction Error Correlation Model Class... [Pg.1527]

The calculation of the temperature in the contact area provides a basis for a classification of the load conditions in terms of their thermal and tribological effect, a practically applicable estimation of service life and a design procedure based on numerical simulation rather than on testing. Thus, a reduction of development efforts will be possible. [Pg.613]

Detailed and extensive information on the UNIFAC method for estimating activity coefficients with application to vapor-liquid equilibria at moderate pressures. [Pg.8]

The method used here is based on a general application of the maximum-likelihood principle. A rigorous discussion is given by Bard (1974) on nonlinear-parameter estimation based on the maximum-likelihood principle. The most important feature of this method is that it attempts properly to account for all measurement errors. A discussion of the background of this method and details of its implementation are given by Anderson et al. (1978). [Pg.97]

In the case of the adiabatic flash, application of a two-dimensional Newton-Raphson iteration to the objective functions represented by Equations (7-13) and (7-14), with Q/F = 0, is used to provide new estimates of a and T simultaneously. The derivatives with respect to a in the Jacobian matrix are found analytically while those with respect to T are found by finite-difference approximation... [Pg.121]

The subroutine is well suited to the typical problems of liquid-liquid separation calculations wehre good estimates of equilibrium phase compositions are not available. However, if very good initial estimates of conjugate-phase compositions are available h. priori, more effective procedures, with second-order convergence, can probably be developed for special applications such as tracing the entire boundary of a two-phase region. [Pg.128]

Analytical models using classical reservoir engineering techniques such as material balance, aquifer modelling and displacement calculations can be used in combination with field and laboratory data to estimate recovery factors for specific situations. These methods are most applicable when there is limited data, time and resources, and would be sufficient for most exploration and early appraisal decisions. However, when the development planning stage is reached, it is becoming common practice to build a reservoir simulation model, which allows more sensitivities to be considered in a shorter time frame. The typical sorts of questions addressed by reservoir simulations are listed in Section 8.5. [Pg.207]

The basic condition of the Standard application - the availability of stable coupled probabilistic or the multiple probabilistic relations between then controlled quality indexes and magnetic characteristics of steel. All the probabilistic estimates, used in the Standard, are applied at confidence level not less than 0,95. General requirements to the means of control and procedure of its performance are also stipulated. Engineers of standard development endeavoured take into consideration the existed practice of technical control performance and test at the enterprises that is why the preparation of object control for the performance of nondestructive test can be done during the process of ordinary acceptance test. It is suggested that every enterprise is operated in correspondence with direct and non-destructive tests, obtained exactly at it, for detailed process chart and definite product type, however the tests have long since been performed after development of the Standard displayed that process gives way to unification. [Pg.25]

In contrast to a direct injection of dc or ac currents in the sample to be tested, the induction of eddy currents by an external excitation coil generates a locally limited current distribution. Since no electrical connection to the sample is required, eddy current NDE is easier to use from a practical point of view, however, the choice of the optimum measurement parameters, like e.g. the excitation frequency, is more critical. Furthermore, the calculation of the current flow in the sample from the measured field distribution tends to be more difficult than in case of a direct current injection. A homogenous field distribution produced by e.g. direct current injection or a sheet inducer [1] allows one to estimate more easily the defect geometry. However, for the detection of technically relevant cracks, these methods do not seem to be easily applicable and sensitive enough, especially in the case of deep lying and small cracks. [Pg.255]

Projection radiography is widely used for pipe inspection and corrosion monitoring. Film digitisation allows a direct access to the local density variations by computer software. Following to a calibration step an interactive estimation of local wall thickness change based on the obtained density variation is possible. The theoretical model is discussed, the limitations of the application range are shown and examples of the practical use are given. The accuracy of this method is compared to results from wall thickness measurements with ultrasonic devices. [Pg.561]

The obtained results for the magnetic bench have allowed to note that defects situated at 12 mm of depth have been observed clearly. This is explained by the high power furnished by the bench, in addition its induction is double alternation rectified. Dimensions of the defect (height and width) are precisely estimated (figure 1). The defect detection at this depth is due to the application of a rectified field, so skin phenomenon is almost absent. [Pg.637]

After having proved the principles a dynamic test facility has been constructed. In this facility it is possible to inject 3 tracers in a flownng liquid consisting of air, oil and water. By changing the relative amounts of the different components it is possible to explore the phase diagram and asses the limits for the measurement principle. Experiments have confirmed the accuracy in parameter estimation to be below 10%, which is considered quite satisfactorily for practical applications. The method will be tested on site at an offshore installation this summer. [Pg.1057]

A number of methods have been described in earlier sections whereby the surface free energy or total energy could be estimated. Generally, it was necessary to assume that the surface area was known by some other means conversely, if some estimate of the specific thermodynamic quantity is available, the application may be reversed to give a surface area determination. This is true if the heat of solution of a powder (Section VII-5B), its heat of immersion (Section X-3A), or its solubility increase (Section X-2) are known. [Pg.576]

Applications of quantum mechanics to chemistry invariably deal with systems (atoms and molecules) that contain more than one particle. Apart from the hydrogen atom, the stationary-state energies caimot be calculated exactly, and compromises must be made in order to estimate them. Perhaps the most useful and widely used approximation in chemistry is the independent-particle approximation, which can take several fomis. Conuiion to all of these is the assumption that the Hamiltonian operator for a system consisting of n particles is approximated by tlie sum... [Pg.24]

One of the most important fiinctions in the application of light scattering is the ability to estimate the object dimensions. As we have discussed earlier for dilute solutions containing large molecules, equation (B 1.9.38) can be used to calculate tire radius of gyration , R, which is defined as the mean square distance from the centre of gravity [12]. The combined use of equation (B 1.9.3 8) equation (B 1.9.39) and equation (B 1.9.40) (tlie Zimm plot) will yield infonnation on R, A2 and molecular weight. [Pg.1396]

There are many different data analysis schemes to estimate the structure and molecular parameters of polymers from the neutron scattering data. Herein, we will present several connnon methods for characterizing the scattering profiles, depending only on the applicable q range. These methods, which were derived based on different assumptions, have... [Pg.1414]

For large Cl calculations, the frill matrix is not fonned and stored in the computer s memory or on disk rather, direct CF methods [ ] identify and compute non-zero and inunediately add up contributions to the sum jCj. Iterative methods [, in which approximate values for the Cj coefficients are refined tlirough sequential application of to the preceding estimate of the vector, are employed to solve... [Pg.2177]


See other pages where Applicators estimation is mentioned: [Pg.163]    [Pg.348]    [Pg.241]    [Pg.567]    [Pg.348]    [Pg.103]    [Pg.567]    [Pg.398]    [Pg.140]    [Pg.282]    [Pg.261]    [Pg.261]    [Pg.15]    [Pg.201]    [Pg.163]    [Pg.348]    [Pg.241]    [Pg.567]    [Pg.348]    [Pg.103]    [Pg.567]    [Pg.398]    [Pg.140]    [Pg.282]    [Pg.261]    [Pg.261]    [Pg.15]    [Pg.201]    [Pg.89]    [Pg.99]    [Pg.75]    [Pg.89]    [Pg.125]    [Pg.153]    [Pg.293]    [Pg.226]    [Pg.347]    [Pg.668]    [Pg.741]    [Pg.2903]   
See also in sourсe #XX -- [ Pg.374 ]




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