Models mass balance

Capture efficiency can also be measured by first estimating workspace emission rates and local exhaust emissions. The local exhaust emission rate equals the duct concentration (mass/volume) multiplied by the duct flow rate (volume/time). The workspace emission rates can be calculated using appropriate mass balance models and measured ventilation rates and workspace concentrations. Capture efficiency is the ratio of duct emission rate to total emission rate (duct plus workspace). ... 

Johnson and Swindell [77] developed a method for evaluating the complete particle distribution and its effect on dissolution. This method divided the distribution into discrete, noncontinuous partitions, from which Johnson and Swindell determined the dissolution of each partition under sink conditions. The dissolution results from each partition value were then summed to give the total dissolution. Oh et al. [82] and Crison and Amidon [83] performed similar calculations using an expression for non-sink conditions based on a macroscopic mass balance model for predicting oral absorption. The dissolution results from this approach could then be tied to the mass balance of the solution phase to predict oral absorption. 

I mass balance model at the farm level Calculation of inputs and outputs. 

Wania F, Persson J, Di Guardo A, McLachlan MS (2000) CoZMo-POP. A fugacity-based multi-comparlmental mass balance model of the fate of persistent organic pollutants in the coastal zone. WECC report 1/2000. Toronto (April)... 

Mackay D (1998) Multimedia mass balance models of chemical distribution and fate. In Schuurmann G, Markert B (eds) Ecotoxicology. Wiley, New York, pp 237-257... 

In this section we describe the key physical-chemical properties and discuss how they may be used to calculate partition coefficients for inclusion in mass balance models. Situations in which data require careful evaluation and use are discussed. 

MASS BALANCE MODELS OF CHEMICAL FATE 1.5.1 Evaluative Environmental Calculations... 

Paterson and Mackay (1985), Mackay and Paterson (1990, 1991), and a recent text (Mackay 2001). Only the salient features are presented here. Three evaluations are completed for each chemical, namely the Level I, II and III fugacity calculations. These calculations can also be done in concentration format instead of fugacity, but for this type of evaluation the fugacity approach is simpler and more instructive. The mass balance models of the types described below can be downloaded for the web site www.trentu.ca/cemc... 

As originally derived, however, the mass balance model has an important (and well acknowledged) limitation implicit in its formulation is the assumption that fluid and minerals in the modeled system remain in isotopic equilibrium over the reaction path. This assumption is equivalent to assuming that isotope exchange between fluid and minerals occurs rapidly enough to maintain equilibrium compositions. 

In this chapter, we develop a mass balance model of the fractionation in reacting systems of the stable isotopes of hydrogen, carbon, oxygen, and sulfur. We then demonstrate application of the model by simulating the isotopic effects of the dolomitization reaction of calcite. 

In this case study, steady-state mass balance models are applied for critical loads calculation for the heavy metals. 

The mass balance model for calculation of critical loads for heavy metals includes the weathering process, the net removal through the crop biomass harvest, leaching, and also leaf uptake and litterfall. Using the simple dynamic way, the distribution between adsorbed and dissolved phases was accounted. 

The chapters have been organized in such a way that, after basic principles have been introduced (Mass Balance), modeling methods (Linear Algebra, Numerical Analysis, Probability and Statistics) are presented before more specifically geochemical... 

Figure 2.5 Mass balance model for intestinal perfusion experiments at steady state (Adapted from Johnson and Amidon [129]).

When analytical uncertainties are propagated through a mass balance model, is... 

As in any other mass balance model of bioprocesses, a strongly nonlinear kinetic behavior is present due to the reaction rates. These rates are given by ... 

Speciet-Mass-Balance Model Performance and Comparative Evaluations... 

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