spectra_data.csv file contains data of bacteria growth and decay process monitored by induced polarization. "quadrature_conductivity_and_bacteria_density.csv file contains the bacteria density during the process of bacteria growth and decay, and at the same time, the change of quadrature conductivity." bacteria_growth_curve_data.csv file contains the data of bacteria growth and decay in the batch experiment. growth_fitting_data.csv file contains the data used to fitting the Monod kinetic parameters of bacteria growth process. decay_fitting_data.csv file contains the?data used to fitting the Monod kinetic parameters of bacteria decay process.