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| Bortoletto-Santos,Ricardo; Guimarães,Gelton Geraldo Fernandes; Roncato Junior,Vanderlei; Cruz,Diego Fernandes da; Polito,Wagner Luiz; Ribeiro,Caue. |
| ABSTRACT: Polymer coatings are used to control the rate of release of plant available nutrients from fertilizers as well as to reduce nutrient losses such as ammonia (NH3) volatilization. Although the literature presents several examples of materials used to coat urea, little is known about nitrogen (N) release properties such as the mechanism involved and phenomena (e.g., pore opening) in the polymer coating. Thus, this study investigated urea release from polyurethane (PU) derived from two renewable raw materials (castor oil and soybean oil), to explain how the oil structure and coating microstructure influence release and urea-N dynamics in soil. The results demonstrated that the profile of urea release and the urea-N mineralization in the soil could be... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Polyurethane; Controlled release; Plant nutrition; Soil fertility; Nitrogen. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162020000101402 |
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| Paiva,Diogo Mendes de; Cantarutti,Reinaldo Bertola; Guimarães,Gelton Geraldo Fernandes; Silva,Ivo Ribeiro da. |
| Urea is the most consumed nitrogen fertilizer in the world. However, its agronomic and economic efficiency is reduced by the volatilization of NH3, which can reach 78 % of the applied nitrogen. The coating of urea granules with acidic compounds obtained by charcoal oxidation has the potential to reduce the volatilization, due to the acidic character, the high buffering capacity and CEC. This work aimed to evaluate the effect of HNO3-oxidized carbon on the control of NH3 volatilization. These compounds were obtained by oxidation of Eucalyptus grandis charcoal, produced at charring temperatures of 350 and 450 ºC, with 4.5 mol L-1 HNO3. The charcoal was oxidized by solubilization in acidic or alkaline medium, similar to the procedure of soil organic matter... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fertilizer; Nitrogen; Urease. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000400016 |
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| Paiva,Diogo Mendes de; Guimarães,Gelton Geraldo Fernandes; Teixeira,Breno Cardoso; Cantarutti,Reinaldo Bertola. |
| ABSTRACT Functionalized charcoal (CHox) incorporated into urea is known for its ability to reduce NH3 volatilization and increase agronomic efficiency. However, it is important to optimize the functionalization process and to elucidate its relationship with the physicochemical properties of CHox for N supply. Thus, charcoal obtained from eucalyptus wood was functionalized with different HNO3 concentrations and reaction times. Ammonia adsorption by CHox was evaluated in chambers with high NH3 concentrations. Dry matter yield, N uptake, and apparent N recovery efficiency of corn plants were evaluated after the application of the urea-CHox mixture to soil in a greenhouse experiment. The properties of CHox, such as pH, isoelectric point, and total acidity... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biochar; NH3 adsorption; NH3 volatilization; Efficient fertilization. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832019000100305 |
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