Abstract: The heat exchanger tray provided herein may include a base, a cover, and a heat exchange coil. The base may include a cutout and a bottom portion with one or more sidewalls forming a serpentine path for wastewater. The cover may be positioned within the cutout of the base to create a space between the base and the cover. The cover may include one or more protruding portions that engage with the one or more sidewalls of the bottom portion of the base to enclose the serpentine path. The heat exchange coil may be positioned in and along at least a portion of the serpentine path between the base and the cover. Fresh water may flow through the heat exchange coil. Wastewater may flow through the serpentine path between the base and the cover, such that the wastewater may heat the fresh water flowing through the heat exchange coil.

Abstract: A prepreg comprising a fibrous reinforcement layer at least partially impregnated with a matrix resin having a first viscosity, a coating of a wet resin having a second viscosity on a first side of the fibrous reinforcement layer, the first viscosity being higher than the second viscosity, both the matrix resin and the wet resin being curable by ultraviolet radiation, a first removable flexible film which acts as a barrier to ultraviolet radiation on a second side of the fibrous reinforcement layer, and optionally a second removable protective flexible film covering the coating of wet resin.

Abstract: A prepreg comprising a fibrous reinforcement layer at least partially impregnated with a matrix resin having a first viscosity, a coating of a wet resin having a second viscosity on a first side of the fibrous reinforcement layer, the first viscosity being higher than the second viscosity, both the matrix resin and the wet resin being curable by ultraviolet radiation, a first removable flexible film which acts as a barrier to ultraviolet radiation on a second side of the fibrous reinforcement layer, and optionally a second removable protective flexible film covering the coating of wet resin.