Abstract: A biomass containment device (BCD) and methods of measuring microbial growth or enzyme activity in the presence of insoluble substrates using the BCD is described. The BCD is compatible with microbial growth and enzyme assays, is sterilizable, is reusable, and the size can be varied to fit any container.

Abstract: A method for making an AWJ mixing tube having a longitudinal bore coated with an abrasion-resistant material, such as diamond. Two blocks having mating longitudinal sides are fastened together prior to machining the longitudinal bore along the junction of their mating surfaces. The blocks are separated and the complementary portions of the longitudinal bore are coated with an abrasion-resistant material. The two blocks are then joined together with the complementary portions of the longitudinal bore aligned to form the longitudinal bore.

Abstract: The invention is a nozzle unit designed for use with wet abrasive materials to clean hard surfaces, such as steel structures. The nozzle unit is formed from two nozzle bodies, which are joined together. Each body has a lengthwise bore therein, with a venturi structure, and a metallic liner is fitted into each bore. Inside the nozzle unit is an annular cavity, which is connected into a source of water and a mixing chamber. The nozzle unit also has air passages therein that connect the mixing chamber with air surrounding the nozzle unit. In a wet blasting operation, an abrasive material, such as sand, is directed into the mixing chamber, where it mixes with water and air to form a wet abrasive stream. The wet stream is then discharged from the nozzle onto the structure to be cleaned.