A one-way locking assembly having an axially moveable member extending through a locking structure. The top wall and an upper portion of each of the opposed side walls defines a first housing shell and the bottom wall and a lower portion of each of the opposed side walls define a second housing shell, the first and second housing shells being separable from one another. Also disclosed is an electrode strip that includes an electrode with a thin working layer. The beam establishes or breaks an electrical link passing through the said at least one electrically conducting body and through the said beam in the different configurations. The compositions and methods can control microbial growth in aqueous streams used for transporting or processing food products.