Félix Monteiro Pereira

  • Citations Per Year
Learn More
The herbicides applied in soils can be easily lost, owing to leaching, volatilization, and bio- and photodegradation. Controlled-release systems using polymeric matrices claim to solve these problems. The movement of the herbicides in the soil is also an important phenomenon to be studied in order to evaluate the loss processes. The development of(More)
Understanding the main phenomena involved in the controlled-release kinetics of herbicides in a water bath is a very important requisite for diffusive- parameter estimation, because, some mathematical models based on Fick's second law for diffusion have been developed to describe the controlled-release kinetic data. However, the validity of these models is(More)
The second Fick's law of diffusion, considering boundary conditions that at both slab faces the concentration of herbicide is equal to zero (sink conditions), has been adequate to describe our kinetic data obtained from experiments on 2,4 -dichlorophenoxyacetic acid, (2,4 - D) released from lignin-based formulations in a water static bath system. However,(More)
Release of herbicides from lignin-based formulations follows a diffusion-controlled mechanism. For mathematical modeling of diffusive transport, the conventional approach is to assume sink conditions at both surfaces of polymeric matrix. This boundary condition proved to be inadequate to describe experimental data obtained in a water dynamic bath system.(More)
In this article, the occurrence of dead core in catalytic particles containing immobilized enzymes is analyzed for the Michaelis-Menten kinetics. An assessment of numerical methods is performed to solve the boundary value problem generated by the mathematical modeling of diffusion and reaction processes under steady state and isothermal conditions. Two(More)
  • 1