Abstract: Systems and methods of treating an inorganic particulate material with an antimicrobial agent are discussed, including: introducing the inorganic particulate material and water to an air swept dryer; introducing the antimicrobial agent to the air swept dryer; and at least partially drying, and optionally at least partially pulverizing, the inorganic particulate material in the presence of the antimicrobial agent forming a treated inorganic particulate material, wherein at least a portion of the antimicrobial agent is exchanged onto and/or into the surface of the treated inorganic particulate material.

Abstract: A concert shell for use either indoors or outdoors wherever music is performed so as to enhance the acoustical quality of the music, and which shell is readily portable, light weight, and which can be readily assembled and disassembled. It comprises a plurality of similarly constructed sections wherein each section is formed of structural members having connected thereto an acoustical shell surface which is formed with a compound convex-concave surface arranged to reverberate and mix the sounds to provide for optimum acoustics.