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Modelling utility

Relational database models utilize memory very efficiently, avoiding repetition of data. It is possible to extract both individual data elements and combinations of them from a table. The main advantage of this structure is that it offers the possibility ofehanging the structure of the database (adding or deleting tables) without... [Pg.235]

The operational model allows simulation of cellular response from receptor activation. In some cases, there may be cooperative effects in the stimulus-response cascades translating activation of receptor to tissue response. This can cause the resulting concentration-response curve to have a Hill coefficient different from unity. In general, there is a standard method for doing this namely, reexpressing the receptor occupancy and/or activation expression (defined by the particular molecular model of receptor function) in terms of the operational model with Hill coefficient not equal to unity. The operational model utilizes the concentration of response-producing receptor as the substrate for a Michaelis-Menten type of reaction, given as... [Pg.55]

High-Conversion Polymerization Kinetic Modeling Utilizing Gel Permeation Chromatography... [Pg.149]

Characterization of Anti-Infective Biological Activity. Acute sepsis models utilizing either Escherichia coli or Staphylococcus aureus intraperitoneal challenge were developed to evaluate the anti-infective properties of PGG in mice. [Pg.47]

The O Flaherty Model utilizes point estimates for parameter values and yields point estimates as output. [Pg.243]

In this section, two models of development were presented, a complex model consisting of a multioperon genome and a cytoplasm, and a simple model based on random Boolean networks. The simpler model was explained in more detail, as it is the basis for the extended example described here. This model utilizes both development and evolution to get to a cell that can develop into a multicellular organism able to seek a chemical trace. [Pg.322]

Table XII would indicate that the effect of water is not described adequately by the model. Utilizing the principle of parsimonious parameterization, one can consider both water and carbon dioxide to be adsorbed and oxygen to be nonadsorbed, resulting in the three-parameter model 4. The residuals in Table XII for model 4, however, are correlated with the oxygen level. Hence model 5 would perhaps be preferable, for it likewise contains only three parameters while allowing adsorbed oxygen. The random residuals of Table XII for model 5 indicate that this model cannot be rejected using the... Table XII would indicate that the effect of water is not described adequately by the model. Utilizing the principle of parsimonious parameterization, one can consider both water and carbon dioxide to be adsorbed and oxygen to be nonadsorbed, resulting in the three-parameter model 4. The residuals in Table XII for model 4, however, are correlated with the oxygen level. Hence model 5 would perhaps be preferable, for it likewise contains only three parameters while allowing adsorbed oxygen. The random residuals of Table XII for model 5 indicate that this model cannot be rejected using the...
Species Extrapolation. The Reitz model used the same species and physiologic parameters that the Corley model utilized (average body weights, organ percentage of body weight, blood flow, etc.) for model predictions. See Table 2-4 for these parameters. However, the model assumed equivalent intrinsic sensitivity of mouse and human hepatocytes. [Pg.134]

The first model to describe the membrane in the above fashion was that of Bernardi and Verbrugge, "° which was based on earlier work by Verbrugge and Hill. " 214 model utilized a dilute solution approach that used the Nernst— Planck equation (eq 29) to describe the movement of protons, except that now v is not equal to zero. The reason is that, because there are two phases, the protons are in the water and the velocity of the water is give by Schlogl s equation ... [Pg.455]

To determine the saturation for any of the models, the capillary pressure must be known at every position within a diffusion medium. Hence, the two-phase models must determine the gas and liquid pressure profiles. In typical two-phase flow in porous media, the movement of both liquid and gas is determined by Darcy s law for each phase and eq 47 relates the two pressures to each other. Many models utilize the capillary pressure functionality as the driving force for the liquid-water flow... [Pg.460]

The approach taken is loosely based on the input-process-output meta-model utilized to transform a problem statement into a functional process. The section Scope definition discusses the intended purpose and potential constraints of the isolation effort, followed by an overview of the Toolbox available to the practitioner (input). The section Method development scouting and scale-up reviews platform-based, highly automated approaches to selectivity scouting, development of the isolation as well as options for scaling up the chromatographic separation depending on purpose and constraints (process). The final section. Performing the task, explores a work breakdown structure approach to the preparative isolation of impurities as a unit operation in the development process (output). [Pg.215]

In the last several years, a set of BBB QSAR models have been developed. One of the top models, developed by Abraham et al. in 2006 [44], reached the predictive limit obtainable from the data set they used. The experimental errors of the logBB measurements were estimated to be 0.3. Their model utilized linear free energy relationship (LFER) as descriptors. For the 328-molecule data set, r2 and RMSE of the MLR model were 0.75 and 0.3 log units, respectively. Interestingly, the RMSE for their test set (n = 164) was even lower (0.25 log units). [Pg.109]

It is obvious that the available prediction models cannot give reliable estimations for oral bioavailability. The prediction errors were typically larger than 20% except the Moda s model, for which the data set only had 250 molecules in contrast, all other models utilized a much larger data set. [Pg.115]

Votano, J.R., Parham, M., Hall, L.H., Kier, L.B., Hall, L.M. Prediction of aqueous solubility based on large datasets using several QSPR models utilizing topological structure representation. Chem. Biodivers. 2004, 1, 1829-41. [Pg.125]

The methodology of 3D-QSAR can be robust for constructing QSAR models utilizing the structure of the compounds and how they will interact with the receptor however, there are several open questions that can complicate any application of this paradigm. The first and most prominent question is Which conformation of the molecule should be used This problem is considered... [Pg.138]

To this point, only models based on the pseudo—phase separation model have been discussed. Mixed micelle models utilizing the mass action model may be necessary for micelles with small aggregation numbers, as demonstrated by Kamrath and Franses ( ). However, even for large micelles, the fundamental basis for the pseudophase separation model needs to be examined. In micelles, how much solvent or how many counterions (bound or in the electrical double layer) should be included in the micellar pseudo-phase is unclear. The difficulty is normally surmounted by assuming that the pseudo—phase consists of only the surfactant components i.e., solvent or counterions are ignored. The validity of treating the micelle on a surfactant—oniy basis has not been verified. Funasaki and Hada (22) have questioned the thermodynamic consistency of such an approach. [Pg.328]

Mass Diffusivity in Liquid Metais and Ailoys. The hard-sphere model of gases works relatively well for self-diffusion in monatomic liquid metals. Several models based on hard-sphere theory exist for predicting the self-diffusivity in liquid metals. One such model utilizes the hard-sphere packing fraction, PF, to determine D (in cm /s) ... [Pg.345]

A flow type model utilizing a polymer pendant sensitizer and catalyst (Fig. 32) was constructed and operated. [Pg.42]

Since that statement, not very much has been done to alleviate the problem, particularly in the electrodynamics model utilized to design and build electrical power systems. Heartbreakingly, the community itself seems predominately bent on defending nonsequiturs and the status quo, rather than correcting a remarkable but aged electrodynamics discipline that is seriously flawed and in great need of revision from the foundations up. [Pg.670]

Examples of the results obtained with the spatially ID model utilizing global NSRC kinetics are given in Figs. 26-33. The reaction kinetic model was validated with real exhaust measurement data from passenger car and heavy-duty commercial vehicle to ensure applicability in the full range of operating conditions encountered. The kinetic equations and the parameters were kept constant for all validation calculations. [Pg.158]

The supernova models utilized below have all been generated by S. Woosley using the Kepler [7] supernova code. The evolution is followed with Kepler until the expansion becomes essentially homologous. At this point the Kepler information is transferred to the spectrum code. It is important to emphasize that once the supernova model has been selected the predicted spectra are generated without adjustable parameters. The adjustable parameters of the model are on the whole those with direct astrophysical relevance, for example the initial stellar mass and amount of mass loss. It is,.of course, feasible and useful to use the comparison of the observed and predicted spectra to refine the supernova model. This, however, has not yet been done except in a rough way. At present, the nebular spectra have been used only to choose broad classes of feasible models and mle out others. For example, the He detonation models for SNIa have been ruled out on the basis of the spectrum[8]. The results presented, therefore, must be viewed accordingly as generic to a whole class of models whose details are still unresolved. [Pg.377]


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See also in sourсe #XX -- [ Pg.146 ]




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