Effect of a Prolonged-Release System of Urea on Nitrogen Losses and Microbial Population Changes in Two Types of Agricultural Soil

Urea is the nitrogen-containing fertilizer most used in agricultural fields; however, the nutrient given by the urea is lost into the environment. The aim of this research was to determine the effect of two soil textures by applying a prolonged-release system of urea (PRSU) on the N losses. This research shows an important decrease of the nitrate and ammonium losses from 24.91 to 87.94%. Also, the microbiological population increases after the application of the PRSU. It was concluded that both soil textures presented the same loss-reduction pattern, where the N from the nitrates and ammonium was reduced in the leachates, increasing the quality of the soil and the microbial population in both soil textures after the PRSU application.

A new design for obtaining of white zein micro- and nanoparticles powder: antisolvent-dialysis method

The objective of this work was propose antisolvent-dialysis as a new, easy, one-step and reproducible method for obtaining white zein micro- and nanoparticles powder. Firstly, the study by SEM of white zein powder predicted micro- and nanoparticles with spherical morphology and average diameters of 243.2 ± 94.5 nm for nanoparticles and 0.74 ± 0.2 μm for microparticles. UV-Vis predicted lower absorbance of 250-500 nm for white zein powder compared to commercial yellow zein powder. FT-IR showed shifting of the main bands to the right, due to changes in particle-shaped microstructure that acquires white zein powder compared to yellow zein powder. In TGA white zein powder showed a decomposition range from 214 to 400 °C, while yellow zein powder from 240 to 400 °C. Therefore, antisolvent-dialysis is new method to obtain white zein micro- and nanoparticles with potential applications such as polymer matrix and white natural coloring.