# IORE.solution: Indeterminate order rate equation kinetics In mkin: Kinetic Evaluation of Chemical Degradation Data

## Description

Function describing exponential decline from a defined starting value, with a concentration dependent rate constant.

## Usage

 `1` ``` IORE.solution(t, parent.0, k__iore, N) ```

## Arguments

 `t` Time. `parent.0` Starting value for the response variable at time zero. `k__iore` Rate constant. Note that this depends on the concentration units used. `N` Exponent describing the nonlinearity of the rate equation

## Value

The value of the response variable at time `t`.

## Note

The solution of the IORE kinetic model reduces to the `SFO.solution` if N = 1. The parameters of the IORE model can be transformed to equivalent parameters of the FOMC mode - see the NAFTA guidance for details.

## References

NAFTA Technical Working Group on Pesticides (not dated) Guidance for Evaluating and Calculating Degradation Kinetics in Environmental Media

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10``` ``` plot(function(x) IORE.solution(x, 100, 0.2, 1.3), 0, 2, ylim = c(0, 100)) fit.fomc <- mkinfit("FOMC", FOCUS_2006_C, quiet = TRUE) fit.iore <- mkinfit("IORE", FOCUS_2006_C, quiet = TRUE) fit.iore.deS <- mkinfit("IORE", FOCUS_2006_C, solution_type = "deSolve", quiet = TRUE) print(data.frame(coef(fit.fomc), coef(fit.iore), coef(fit.iore.deS), row.names = paste("model par", 1:3))) print(rbind(fomc = endpoints(fit.fomc)\$distimes, iore = endpoints(fit.iore)\$distimes, iore.deS = endpoints(fit.iore)\$distimes)) ```

### Example output

```Loading required package: minpack.lm