conc2frac {transmem}

Creates a data frame as a complete self-contained transport data set

Description

The function transforms the data contained in concentration vectors of feed and strip phases to a data frame that contains the complete data of a transport process. This new data frame can be used by several functions inside the package. The output data frame may contain normalized fractions remaining in the feed and already transported to the strip phase, or the original data provided in concentration units.

Usage

conc2frac(feed, strip, time = NULL, correct.strip = FALSE, normalize = TRUE)

Arguments

feed

Numeric vector with concentrations in the feed phase.

strip

Numeric vector with concentrations in the strip phase.

time

Numeric vector with time at which the aliquots were sampled. It is an optional parameter. If not provided, regular unitary time intervals are assumed.

correct.strip

Logical. If FALSE, the default, the information about the amount transported to the strip phase is used as received but if it is set to TRUE, the initial concentration in the strip phase is substracted to all concentrations in the same phase. This is particularly useful when the blank signal is significative or there is background noise.

normalize

Logical. If TRUE, the default, all concentrations are divided by the initial concentration in the feed phase to give results in fraction units.

Details

The change in concentration of species in the feed and strip phases as a function of time are the main magnitudes being measured in processes involving transport across membranes. The best form to deal with such data is inside a dataframe containing the information about the concentration of given species in both phases and the time transcurred.

Usually, this function is required after using signal2conc wich convert instrumental signals to concentrations.

Value

Data frame with the transport proccess information

Author(s)

Cristhian Paredes, [e-mail]

Eduardo Rodriguez de San Miguel, [e-mail]

Examples

  transData <- conc2frac(feed = c(0.200, 0.169, 0.152, 0.141, 0.138),
                         strip = c(0.000, 0.035, 0.045, 0.062, 0.069),
                         time = c(0, 2, 4, 6, 8))
  print(transData)