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Variable Parameters

Both temperature and pressure are important parameters/variables in NMR measurements of homogeneous hydrogenation catalysts. Usually, a certain hydrogen pressure is needed to form the active catalyst. The temperature controls the rate of reactions. Sometimes, temperatures above room temperature are needed for example, the reaction shown in Figure 11.3 occurs at a hydrogen pressure of 3 atmos and temperatures above 318 K. In other cases, intermediates can only be observed at temperatures below room temperature. Modern NMR instruments routinely allow measurements to be made in the range of, for example 170 to 410 K, but this range can easily be extended by the use of special NMR probes. [Pg.307]

It s easy to see the direct correspondence The participants of the action are drawn as, and are, associations of the reified action the action s parameters—variable values we don t bother to depict as links on the diagram—are the object s attributes (see Figure... [Pg.275]

Using the function get par, m the values of the parameters corresponding to the names in s, par str are collected into the vector of variable parameters s. par. The partner function put par. m is used within nglm3, m to do the opposite i.e. to update after each iteration all individual parameter variables corresponding to the names given in s, par str. [Pg.171]

Figure 3.9D shows the form of the curve of the excess Gibbs free energy of mixing obtained with Van Laar parameters variable with T. the mixture is subregular— i.e., asymmetric over the binary compositional field. [Pg.170]

Double degeneracy occurs for X = X2 = 0. When Xi and X2 are different from zero but remain small, the following change of parameters, variables, and time scale ... [Pg.184]

A sensor is a part of or an element in a measuring chain which converts an environmental parameter (variable) into a signal. Environmental parameters are temperature, pressure and the concentration of gases. [Pg.288]

Table 16. New indices and modified parameters/variables for restricted recourse... Table 16. New indices and modified parameters/variables for restricted recourse...
The classical approach to the synthesis of nanostructured catalysts and materials of different morphologies and grain sizes has been one that heavily relies on detailed experimentation, altering the chemistry of synthesis to achieve the desired material. Our view has been that this approach, although successful for the synthesis of a wide range of nanostructured materials, requires too many experiments and is generally not a priori predictable. As a consequence, the direction of nanostructured materials synthesis in our laboratories has been to examine the application of various mechanical techniques that have sufficient process-parameter variability to afford... [Pg.18]

Several papers on this approach convert the optimization problem to one using continuous "structural parameter" variables (Umeda, Hirai and Ichikawa (1972) Umeda, Shindo and Tazaki (1972) Osakada and Fan (1973) Ichikawa and Fan (1973) Mishra, Fan and Erickson (1973a,b) Himmelblau (1975) Sargent and Gaminibandara (1975)). Here the idea is to split the exit flow of each unit into part-flows to each of the potential target... [Pg.78]

The nature of the steps which have to be carried out now makes this dimensional matrix less than ideal because it is necessary to know that each of the individual elements of the residual matrix will appear in only one of the dimensionless numbers, while the elements of the core matrix may appear as fillers in the denominators of all of them. The residual matrix should therefore be loaded with essential variables such as the target quantity and the most important physical properties and process-related parameters. Variables with an, as yet, uncertain influence on the process must also be included in this group. If, later, these variables are found to be irrelevant, only the dimensionless number concerned will have to be deleted while leaving the others unaltered. [Pg.17]

Explanation of parameter variability using covariates can be achieved ... [Pg.313]

First, if the compound was cleared mainly by hepatic metabolism in the animal species tested and if human hepatocytes in vitro suggest the same will be true in humans, then the measured hepatocyte clearance may be used in a process called in vitro/in vivo scaling (20, pp. 207-228) to provide an estimate of the human intrinsic clearance. The application of Equation 5 then gives an estimate of the human systemic clearance. Second, the animal PK parameters of CL and Vj can be subjected to allometric scaling (20, pp. 207-228) whereby the PK parameter is related to a measurable allometric variable such as body mass, body surface area, heart rate, and so forth. (21) by fitting these parameter-variable pairs for several species to an empirical power equation of the form... [Pg.2069]

Parameters and Operational Conditions for Simulation of Competitive Transport Process Parameter Variables... [Pg.384]

On the other hand, there are also several challenges associated with the use of CMF for beer clarihcation slight variability of permeate quality (either higher turbidity, or protein and aroma retenhon) between different types of beer hltered with the same equipment and parameters, variability in fluxes due to varying ingredient concentrations in different batches or in different beer brands, and the need for intensive cleaning due to membrane fouhng. [Pg.569]

A variety of other criteria have been developed that may also be useful. It is hoped that each criterion (parameter variability, graphical output, AIC, F test, etc.) will complement each other, allowing the analyst to make an objective decision. [Pg.2768]

The correlation between the probability of moribundity (p) and a plasma TK parameter variable (a variable of interest, or VOI, such as Cmax or AUC) from... [Pg.318]

The simplest method of accounting for variability consists in identifying the parameters, experimental data, and model output with an average or reference individual [45], One shortcoming of this approach is that although general model behavior is representative, much of the actual population may not be well described. Methods attempting to explicitly account for variability and uncertainty include Monte Carlo simulations [18,46,48], Bayesian population methods [49-51,53,56], the use of fuzzy sets [44,52], and other probability based methods [43], Monte Carlo simulations, which model the parameter variability in terms of probability distributions, are the most common methods. Each individual is characterized by a set of parameters whose values are drawn from a... [Pg.46]

Figure 6.1. Relationships among the processing parameters, variables and properties of the deposit [2]... Figure 6.1. Relationships among the processing parameters, variables and properties of the deposit [2]...
Provided r] values are deemed reliable, they can be used in scatter matrix plots to investigate correlations between parameters or in QQ plots or histograms to assess appropriateness of the selected parametric shape of parameter variability. Models... [Pg.199]

One of the most potent applications of pharmacometrics is the informative construction of clinical trials by using clinical trial simulation (CTS). Population PM models are of great value when used in CTS because estimates of typical parameters along with parameter variability can be incorporated. There are three basic types of models needed to execute a CTS an input-output model, a covariate model, and an execution model. These are described in detail in Chapter 34 of this book. Clinical trial simulation can improve pediatric study structure by examining the impact of many important factors such as dropouts, choosing varying endpoints, and deviations from protocol. Pediatric PM models find great utility when applied to CTS. [Pg.970]

Parameter/ Variable Description Value Code Variable/Line Number (Cxx Lyy)... [Pg.1081]

In this paper it has been demonstrated that the CRAMS system can directly aid the physical scientist to design experiments for testing any proposed reaction mechcinism. In CRAMS two kinds of parameters, variable (concentration-time... [Pg.67]


See other pages where Variable Parameters is mentioned: [Pg.520]    [Pg.83]    [Pg.91]    [Pg.88]    [Pg.271]    [Pg.519]    [Pg.173]    [Pg.173]    [Pg.18]    [Pg.152]    [Pg.172]    [Pg.173]    [Pg.183]    [Pg.216]    [Pg.93]    [Pg.158]    [Pg.394]    [Pg.8]    [Pg.597]    [Pg.367]    [Pg.216]    [Pg.273]    [Pg.219]    [Pg.73]   
See also in sourсe #XX -- [ Pg.182 ]




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