Abstract: This disclosure relates to slow- and controlled-release fertilizers (S-CRF), and more particularly to a microelement amino acid chelate-urea formaldehyde (UF) slow-release fertilizer and a method for preparing the same by reactive extrusion. The microelement amino acid chelate-UF slow-release fertilizer includes a biodegradable UF polymer and a microelement amino acid chelate. The macromolecular chains of the biodegradable UF polymer interpenetrate in the cross-linked network structure of the chelate, so as to form a polymer composite with a semi-interpenetrating network structure.

Abstract: A sulfonated lignin as a by-product of papermaking wood pulp/urea-formaldehyde (UF) fertilizer and a method for preparing the same by a reactive extrusion and granulation process are provided. The method includes: mixing a hydroxymethylated sulfonated lignin solution with a hydroxymethyl-urea solution followed by feeding into a reaction-extrusion integrated machine and reaction at a preset temperature for a preset time; subjecting the reaction mixture to extrusion through a twin-screw extruder to obtain a strip product; and drying the strip product followed by granulation to obtain a sulfonated lignin as a by-product of papermaking wood pulp/UF fertilizer columnar particles. Sulfonated lignin molecules are introduced to the main chain of the UF macromolecules to reduce the polymerization degree and crystallinity of the UF fertilizer, so as to regulate the nitrogen release rate.

Abstract: A method for performing model predictive maintenance (MPM) of building equipment includes obtaining a first objective function that defines a cost of operating the building equipment and at least one of replacing the building equipment or performing maintenance on the building equipment as a function of operating decisions and at least one of replacement decisions or maintenance decisions for the building equipment for multiple short-term time steps within a short-term horizon. The method also includes performing a first optimization of the first objective function to generate a short-term maintenance and replacement schedule for the building equipment over a duration of the short-term horizon. The method also includes using a result of the first optimization to perform a second optimization of a second objective function to generate a long-term maintenance and replacement schedule for the building equipment over a duration of a long-term horizon.

Abstract: A method for performing model predictive maintenance (MPM) of building equipment includes obtaining a first objective function that defines a cost of operating the building equipment and at least one of replacing the building equipment or performing maintenance on the building equipment as a function of operating decisions and at least one of replacement decisions or maintenance decisions for the building equipment for multiple short-term time steps within a short-term horizon. The method also includes performing a first optimization of the first objective function to generate a short-term maintenance and replacement schedule for the building equipment over a duration of the short-term horizon. The method also includes using a result of the first optimization to perform a second optimization of a second objective function to generate a long-term maintenance and replacement schedule for the building equipment over a duration of a long-term horizon.