Devices and methods for controlling the properties of chemical species during time-dependent processes. A device includes a reactor for containing one or more chemical species of a time-dependent process, an extraction pump for automatically and continuously extracting an amount of the one or more chemical species from the reactor, one or more detectors for measuring property changes of the one or more extracted chemical species and generating a continuous stream of data related to the one or more property changes to the one or more chemical species during a time interval, and a process controller configured to fit the continuous stream of data to a mathematical function to predict one or more properties of the one or more chemical species at a future time point and make one or more process decisions based on the prediction of one or more properties at the future time point.