Yapay Zeka Hızlı Bakış & Çıkarımlar
AI InsightThe release rates of coated beads were between 723%-6815% greater than uncoated beads (control) with pH 4 having the greatest difference.
📌 3 Maddede Bu Makale
Abstract
Nitrogen is essential to plant growth, yet the ineffective use of nitrate fertilizers causes excess nutrient runoff, increasing eutrophication. Unlike common immediate release fertilizers, this project developed a novel pH-responsive slow-release mechanism for environmentally friendly fertilizers. Specifically, the targeted release is at the pH of typical rainwater (~5.6) to increase nutrient uptake for plants during irrigation and reduce nutrient runoff. Calcium chloride was crosslinked with sodium alginate, potassium nitrate, and crystal violet (CV+) to form fertilizer beads. These were coated with chitosan and sodium tripolyphosphate, enabling for a slow release of nitrates at specific pH’s. CV+ acted as a stoichiometric proxy of nitrate concentrations, which were determined using ultraviolet-visible spectrophotometry. The release of nitrates from the beads, at various pH’s, were measured over 90 minutes with aliquots taken every 5 minutes from 4 different pH (4-7) buffer solutions. Experimental results showed release rates of nitrates in buffer solutions ranging from 0.2160–0.5739 μM/min. The highest rates were found at pH 6 followed closely by pH 5. The beads at pH 6 had the least remaining mole percent of nitrates after 90 minutes (42%). Other groups ranged from 45%-77%. Nitrate release rates aligned with the Higuchi model, suggesting diffusion-controlled release through a crosslinked polymer matrix. The release rates of coated beads were between 723%-6815% greater than uncoated beads (control) with pH 4 having the greatest difference.